merge

.editorconfig

@@ -0,0 +1,10 @@
+
+root = true
+
+[{src,scripts}/**.{ts,json,js}]
+end_of_line = crlf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+indent_style = space
+indent_size = 4

README.md

@@ -1,6 +1,8 @@
 [![Build Status](https://travis-ci.org/Microsoft/TypeScript.svg?branch=master)](https://travis-ci.org/Microsoft/TypeScript)
 [![Issue Stats](http://issuestats.com/github/Microsoft/TypeScript/badge/pr)](http://issuestats.com/github/microsoft/typescript)
 [![Issue Stats](http://issuestats.com/github/Microsoft/TypeScript/badge/issue)](http://issuestats.com/github/microsoft/typescript)
+[![npm version](https://badge.fury.io/js/typescript.svg)](http://badge.fury.io/js/typescript)
+[![Downloads](http://img.shields.io/npm/dm/TypeScript.svg)](https://npmjs.org/package/typescript)
 
 # TypeScript
 

scripts/VSDevMode.ps1

@@ -37,12 +37,38 @@ if(!(Test-Path $tsRegKey)){
 }
 
 if($tsScript -ne ""){
-    if(!(Test-Path $tsScript)){
-        Throw "Could not locate the TypeScript language service script at ${tsScript}"
+    $tsScriptServices =  "${tsScript}\typescriptServices.js"
+    $tsScriptlib = "${tsScript}\lib.d.ts"
+    $tsES6Scriptlib = "${tsScript}\lib.es6.d.ts"
+    
+    if(!(Test-Path $tsScriptServices)){
+        Throw "Could not locate the TypeScript language service script at ${tsScriptServices}"
+    }
+    else {
+        $path = resolve-path ${tsScriptServices}
+        Set-ItemProperty -path $tsRegKey -name CustomTypeScriptServicesFileLocation -value "${path}"
+        Write-Host "Enabled custom TypeScript language service at ${path} for Dev${vsVersion}"
+    }
+
+    if(!(Test-Path $tsScriptlib)){
+        Throw "Could not locate the TypeScript default library at ${tsScriptlib}"
+    }
+    else {
+        $path = resolve-path ${tsScriptlib}
+        Set-ItemProperty -path $tsRegKey -name CustomDefaultLibraryLocation -value "${path}"
+        Write-Host "Enabled custom TypeScript default library at ${path} for Dev${vsVersion}"
+    }
+
+    if(!(Test-Path $tsES6Scriptlib)){
+        Throw "Could not locate the TypeScript default ES6 library at ${tsES6Scriptlib}"
+    }
+    else {
+        $path = resolve-path ${tsES6Scriptlib}
+        Set-ItemProperty -path $tsRegKey -name CustomDefaultES6LibraryLocation -value "${path}"
+        Write-Host "Enabled custom TypeScript default ES6 library at ${path} for Dev${vsVersion}"
     }
-    Set-ItemProperty -path $tsRegKey -name CustomTypeScriptServicesFileLocation -value "${tsScript}"
-    Write-Host "Enabled custom TypeScript language service at ${tsScript} for Dev${vsVersion}"
 }
+
 if($enableDevMode){
     Set-ItemProperty -path $tsRegKey -name EnableDevMode -value 1
     Write-Host "Enabled developer mode for Dev${vsVersion}"

src/compiler/binder.ts

@@ -67,7 +67,8 @@ module ts {
 
         if (!file.locals) {
             file.locals = {};
-            container = blockScopeContainer = file;
+            container = file;
+            setBlockScopeContainer(file, /*cleanLocals*/ false);
             bind(file);
             file.symbolCount = symbolCount;
         }
@@ -77,6 +78,13 @@ module ts {
             return new Symbol(flags, name);
         }
 
+        function setBlockScopeContainer(node: Node, cleanLocals: boolean) {
+            blockScopeContainer = node;
+            if (cleanLocals) {
+                blockScopeContainer.locals = undefined;
+            }
+        }
+
         function addDeclarationToSymbol(symbol: Symbol, node: Declaration, symbolKind: SymbolFlags) {
             symbol.flags |= symbolKind;
             if (!symbol.declarations) symbol.declarations = [];
@@ -236,7 +244,13 @@ module ts {
             }
 
             if (isBlockScopeContainer) {
-                blockScopeContainer = node;
+                // in incremental scenarios we might reuse nodes that already have locals being allocated
+                // during the bind step these locals should be dropped to prevent using stale data.
+                // locals should always be dropped unless they were previously initialized by the binder
+                // these cases are:
+                // - node has locals (symbolKind & HasLocals) !== 0
+                // - node is a source file
+                setBlockScopeContainer(node, /*cleanLocals*/  (symbolKind & SymbolFlags.HasLocals) === 0 && node.kind !== SyntaxKind.SourceFile);
             }
 
             forEachChild(node, bind);
@@ -342,14 +356,7 @@ module ts {
         }
 
         function bindCatchVariableDeclaration(node: CatchClause) {
-            var symbol = createSymbol(SymbolFlags.FunctionScopedVariable, node.name.text || "__missing");
-            addDeclarationToSymbol(symbol, node, SymbolFlags.FunctionScopedVariable);
-            var saveParent = parent;
-            var savedBlockScopeContainer = blockScopeContainer;
-            parent = blockScopeContainer = node;
-            forEachChild(node, bind);
-            parent = saveParent;
-            blockScopeContainer = savedBlockScopeContainer;
+            bindChildren(node, /*symbolKind:*/ 0, /*isBlockScopeContainer:*/ true);
         }
 
         function bindBlockScopedVariableDeclaration(node: Declaration) {
@@ -377,6 +384,7 @@ module ts {
 
         function bind(node: Node) {
             node.parent = parent;
+            
             switch (node.kind) {
                 case SyntaxKind.TypeParameter:
                     bindDeclaration(<Declaration>node, SymbolFlags.TypeParameter, SymbolFlags.TypeParameterExcludes, /*isBlockScopeContainer*/ false);
@@ -389,7 +397,7 @@ module ts {
                     if (isBindingPattern((<Declaration>node).name)) {
                         bindChildren(node, 0, /*isBlockScopeContainer*/ false);
                     }
-                    else if (getCombinedNodeFlags(node) & NodeFlags.BlockScoped) {
+                    else if (isBlockOrCatchScoped(<Declaration>node)) {
                         bindBlockScopedVariableDeclaration(<Declaration>node);
                     }
                     else {

src/compiler/checker.ts

@@ -97,6 +97,7 @@ module ts {
         var globalRegExpType: ObjectType;
         var globalTemplateStringsArrayType: ObjectType;
         var globalESSymbolType: ObjectType;
+        var globalIterableType: ObjectType;
 
         var anyArrayType: Type;
 
@@ -416,13 +417,6 @@ module ts {
                             break loop;
                         }
                         break;
-                    case SyntaxKind.CatchClause:
-                        var id = (<CatchClause>location).name;
-                        if (name === id.text) {
-                            result = location.symbol;
-                            break loop;
-                        }
-                        break;
                 }
                 lastLocation = location;
                 location = location.parent;
@@ -451,7 +445,8 @@ module ts {
                 }
                 if (result.flags & SymbolFlags.BlockScopedVariable) {
                     // Block-scoped variables cannot be used before their definition
-                    var declaration = forEach(result.declarations, d => getCombinedNodeFlags(d) & NodeFlags.BlockScoped ? d : undefined);
+                    var declaration = forEach(result.declarations, d => isBlockOrCatchScoped(d) ? d : undefined);
+
                     Debug.assert(declaration !== undefined, "Block-scoped variable declaration is undefined");
                     if (!isDefinedBefore(declaration, errorLocation)) {
                         error(errorLocation, Diagnostics.Block_scoped_variable_0_used_before_its_declaration, declarationNameToString(declaration.name));
@@ -595,13 +590,13 @@ module ts {
             }
 
             if (name.kind === SyntaxKind.Identifier) {
-                var symbol = resolveName(location,(<Identifier>name).text, meaning, Diagnostics.Cannot_find_name_0, <Identifier>name);
+                var symbol = resolveName(location, (<Identifier>name).text, meaning, Diagnostics.Cannot_find_name_0, <Identifier>name);
                 if (!symbol) {
                     return;
                 }
             }
             else if (name.kind === SyntaxKind.QualifiedName) {
-                var namespace = resolveEntityName(location,(<QualifiedName>name).left, SymbolFlags.Namespace);
+                var namespace = resolveEntityName(location, (<QualifiedName>name).left, SymbolFlags.Namespace);
                 if (!namespace || namespace === unknownSymbol || getFullWidth((<QualifiedName>name).right) === 0) return;
                 var symbol = getSymbol(getExportsOfSymbol(namespace), (<QualifiedName>name).right.text, meaning);
                 if (!symbol) {
@@ -751,7 +746,10 @@ module ts {
                     forEach(symbol.declarations, node => {
                         if (node.kind === SyntaxKind.SourceFile || node.kind === SyntaxKind.ModuleDeclaration) {
                             forEach((<ExportContainer>node).exportStars, exportStar => {
-                                visit(resolveExternalModuleName(exportStar, exportStar.moduleSpecifier));
+                                var moduleSymbol = resolveExternalModuleName(exportStar, exportStar.moduleSpecifier);
+                                if (moduleSymbol) {
+                                    visit(moduleSymbol);
+                                }
                             });
                         }
                     });
@@ -1862,6 +1860,9 @@ module ts {
             if (declaration.parent.parent.kind === SyntaxKind.ForInStatement) {
                 return anyType;
             }
+            if (declaration.parent.parent.kind === SyntaxKind.ForOfStatement) {
+                return getTypeForVariableDeclarationInForOfStatement(<ForOfStatement>declaration.parent.parent);
+            }
             if (isBindingPattern(declaration.parent)) {
                 return getTypeForBindingElement(<BindingElement>declaration);
             }
@@ -1994,7 +1995,7 @@ module ts {
                 }
                 // Handle catch clause variables
                 var declaration = symbol.valueDeclaration;
-                if (declaration.kind === SyntaxKind.CatchClause) {
+                if (declaration.parent.kind === SyntaxKind.CatchClause) {
                     return links.type = anyType;
                 }
                 // Handle variable, parameter or property
@@ -3153,8 +3154,8 @@ module ts {
             return resolveName(undefined, name, meaning, diagnostic, name);
         }
 
-        function getGlobalType(name: string): ObjectType {
-            return getTypeOfGlobalSymbol(getGlobalTypeSymbol(name), 0);
+        function getGlobalType(name: string, arity = 0): ObjectType {
+            return getTypeOfGlobalSymbol(getGlobalTypeSymbol(name), arity);
         }
 
         function getGlobalESSymbolConstructorSymbol() {
@@ -3536,7 +3537,7 @@ module ts {
                         isContextSensitive((<ConditionalExpression>node).whenFalse);
                 case SyntaxKind.BinaryExpression:
                     return (<BinaryExpression>node).operatorToken.kind === SyntaxKind.BarBarToken &&
-                    (isContextSensitive((<BinaryExpression>node).left) || isContextSensitive((<BinaryExpression>node).right));
+                        (isContextSensitive((<BinaryExpression>node).left) || isContextSensitive((<BinaryExpression>node).right));
                 case SyntaxKind.PropertyAssignment:
                     return isContextSensitive((<PropertyAssignment>node).initializer);
                 case SyntaxKind.MethodDeclaration:
@@ -5002,7 +5003,7 @@ module ts {
                         break;
                     case SyntaxKind.PrefixUnaryExpression:
                         if ((<PrefixUnaryExpression>expr).operator === SyntaxKind.ExclamationToken) {
-                            return narrowType(type,(<PrefixUnaryExpression>expr).operand, !assumeTrue);
+                            return narrowType(type, (<PrefixUnaryExpression>expr).operand, !assumeTrue);
                         }
                         break;
                 }
@@ -5073,7 +5074,7 @@ module ts {
                         nodeLinks.importOnRightSide = symbol;
                     }
                 }
-                
+
                 if (symbolLinks.referenced) {
                     markLinkedImportsAsReferenced(<ImportEqualsDeclaration>getDeclarationOfKind(symbol, SyntaxKind.ImportEqualsDeclaration));
                 }
@@ -5081,10 +5082,63 @@ module ts {
 
             checkCollisionWithCapturedSuperVariable(node, node);
             checkCollisionWithCapturedThisVariable(node, node);
+            checkBlockScopedBindingCapturedInLoop(node, symbol);
 
             return getNarrowedTypeOfSymbol(getExportSymbolOfValueSymbolIfExported(symbol), node);
         }
 
+        function isInsideFunction(node: Node, threshold: Node): boolean {
+            var current = node;
+            while (current && current !== threshold) {
+                if (isAnyFunction(current)) {
+                    return true;
+                }
+                current = current.parent;
+            }
+
+            return false;
+        }
+
+        function checkBlockScopedBindingCapturedInLoop(node: Identifier, symbol: Symbol): void {
+            if (languageVersion >= ScriptTarget.ES6 ||
+                (symbol.flags & SymbolFlags.BlockScopedVariable) === 0 ||
+                symbol.valueDeclaration.parent.kind === SyntaxKind.CatchClause) {
+                return;
+            }
+
+            // - check if binding is used in some function
+            // (stop the walk when reaching container of binding declaration)
+            // - if first check succeeded - check if variable is declared inside the loop
+
+            // nesting structure:
+            // (variable declaration or binding element) -> variable declaration list -> container
+            var container: Node = symbol.valueDeclaration;
+            while (container.kind !== SyntaxKind.VariableDeclarationList) {
+                container = container.parent;
+            }
+            // get the parent of variable declaration list
+            container = container.parent;
+            if (container.kind === SyntaxKind.VariableStatement) {
+                // if parent is variable statement - get its parent
+                container = container.parent;
+            }
+            
+            var inFunction = isInsideFunction(node.parent, container);
+
+            var current = container;
+            while (current && !nodeStartsNewLexicalEnvironment(current)) {
+                if (isIterationStatement(current, /*lookInLabeledStatements*/ false)) {
+                    if (inFunction) {
+                        grammarErrorOnFirstToken(current, Diagnostics.Loop_contains_block_scoped_variable_0_referenced_by_a_function_in_the_loop_This_is_only_supported_in_ECMAScript_6_or_higher, declarationNameToString(node));
+                    }
+                    // mark value declaration so during emit they can have a special handling
+                    getNodeLinks(<VariableDeclaration>symbol.valueDeclaration).flags |= NodeCheckFlags.BlockScopedBindingInLoop;
+                    break;
+                }
+                current = current.parent;
+            }
+        }
+
         function captureLexicalThis(node: Node, container: Node): void {
             var classNode = container.parent && container.parent.kind === SyntaxKind.ClassDeclaration ? container.parent : undefined;
             getNodeLinks(node).flags |= NodeCheckFlags.LexicalThis;
@@ -5441,7 +5495,7 @@ module ts {
                         return propertyType;
                     }
                 }
-                
+
                 return isNumericName(element.name) && getIndexTypeOfContextualType(type, IndexKind.Number) ||
                     getIndexTypeOfContextualType(type, IndexKind.String);
             }
@@ -5450,14 +5504,17 @@ module ts {
         }
 
         // In an array literal contextually typed by a type T, the contextual type of an element expression at index N is
-        // the type of the property with the numeric name N in T, if one exists. Otherwise, it is the type of the numeric
-        // index signature in T, if one exists.
+        // the type of the property with the numeric name N in T, if one exists. Otherwise, if T has a numeric index signature,
+        // it is the type of the numeric index signature in T. Otherwise, in ES6 and higher, the contextual type is the iterated
+        // type of T.
         function getContextualTypeForElementExpression(node: Expression): Type {
             var arrayLiteral = <ArrayLiteralExpression>node.parent;
             var type = getContextualType(arrayLiteral);
             if (type) {
                 var index = indexOf(arrayLiteral.elements, node);
-                return getTypeOfPropertyOfContextualType(type, "" + index) || getIndexTypeOfContextualType(type, IndexKind.Number);
+                return getTypeOfPropertyOfContextualType(type, "" + index)
+                    || getIndexTypeOfContextualType(type, IndexKind.Number)
+                    || (languageVersion >= ScriptTarget.ES6 ? checkIteratedType(type, /*expressionForError*/ undefined) : undefined);
             }
             return undefined;
         }
@@ -6034,7 +6091,7 @@ module ts {
             if (!leftHandSideSymbol) {
                 return false;
             }
-            
+
             var globalESSymbol = getGlobalESSymbolConstructorSymbol();
             if (!globalESSymbol) {
                 // Already errored when we tried to look up the symbol
@@ -6308,7 +6365,7 @@ module ts {
                     // unless we're reporting errors
                     var argType = i === 0 && node.kind === SyntaxKind.TaggedTemplateExpression ? globalTemplateStringsArrayType :
                         arg.kind === SyntaxKind.StringLiteral && !reportErrors ? getStringLiteralType(<LiteralExpression>arg) :
-                        checkExpressionWithContextualType(arg, paramType, excludeArgument && excludeArgument[i] ? identityMapper : undefined);
+                            checkExpressionWithContextualType(arg, paramType, excludeArgument && excludeArgument[i] ? identityMapper : undefined);
                     // Use argument expression as error location when reporting errors
                     if (!checkTypeRelatedTo(argType, paramType, relation, reportErrors ? arg : undefined,
                         Diagnostics.Argument_of_type_0_is_not_assignable_to_parameter_of_type_1)) {
@@ -6759,11 +6816,6 @@ module ts {
         }
 
         function checkTaggedTemplateExpression(node: TaggedTemplateExpression): Type {
-            // Grammar checking
-            if (languageVersion < ScriptTarget.ES6) {
-                grammarErrorOnFirstToken(node.template, Diagnostics.Tagged_templates_are_only_available_when_targeting_ECMAScript_6_and_higher);
-            }
-
             return getReturnTypeOfSignature(getResolvedSignature(node));
         }
 
@@ -6938,7 +6990,7 @@ module ts {
 
             if (produceDiagnostics && node.kind !== SyntaxKind.MethodDeclaration && node.kind !== SyntaxKind.MethodSignature) {
                 checkCollisionWithCapturedSuperVariable(node, (<FunctionExpression>node).name);
-                checkCollisionWithCapturedThisVariable(node,(<FunctionExpression>node).name);
+                checkCollisionWithCapturedThisVariable(node, (<FunctionExpression>node).name);
             }
 
             return type;
@@ -6972,7 +7024,7 @@ module ts {
             return true;
         }
 
-        function checkReferenceExpression(n: Node, invalidReferenceMessage: DiagnosticMessage, constantVarianleMessage: DiagnosticMessage): boolean {
+        function checkReferenceExpression(n: Node, invalidReferenceMessage: DiagnosticMessage, constantVariableMessage: DiagnosticMessage): boolean {
             function findSymbol(n: Node): Symbol {
                 var symbol = getNodeLinks(n).resolvedSymbol;
                 // Because we got the symbol from the resolvedSymbol property, it might be of kind
@@ -7039,7 +7091,7 @@ module ts {
                 return false;
             }
             if (isConstVariableReference(n)) {
-                error(n, constantVarianleMessage);
+                error(n, constantVariableMessage);
                 return false;
             }
             return true;
@@ -7231,7 +7283,7 @@ module ts {
                         var propName = "" + i;
                         var type = sourceType.flags & TypeFlags.Any ? sourceType :
                             isTupleLikeType(sourceType) ? getTypeOfPropertyOfType(sourceType, propName) :
-                            getIndexTypeOfType(sourceType, IndexKind.Number);
+                                getIndexTypeOfType(sourceType, IndexKind.Number);
                         if (type) {
                             checkDestructuringAssignment(e, type, contextualMapper);
                         }
@@ -7385,7 +7437,7 @@ module ts {
                     if (!checkForDisallowedESSymbolOperand(operator)) {
                         return booleanType;
                     }
-                    // Fall through
+                // Fall through
                 case SyntaxKind.EqualsEqualsToken:
                 case SyntaxKind.ExclamationEqualsToken:
                 case SyntaxKind.EqualsEqualsEqualsToken:
@@ -7409,7 +7461,7 @@ module ts {
                     return rightType;
             }
 
-            // Return type is true if there was no error, false if there was an error.
+            // Return true if there was no error, false if there was an error.
             function checkForDisallowedESSymbolOperand(operator: SyntaxKind): boolean {
                 var offendingSymbolOperand =
                     someConstituentTypeHasKind(leftType, TypeFlags.ESSymbol) ? node.left :
@@ -7713,8 +7765,8 @@ module ts {
             }
             // TODO (yuisu): Remove this check in else-if when SyntaxKind.Construct is moved and ambient context is handled
             else if (node.kind === SyntaxKind.FunctionType || node.kind === SyntaxKind.FunctionDeclaration || node.kind === SyntaxKind.ConstructorType ||
-                      node.kind === SyntaxKind.CallSignature || node.kind === SyntaxKind.Constructor ||
-                      node.kind === SyntaxKind.ConstructSignature){
+                node.kind === SyntaxKind.CallSignature || node.kind === SyntaxKind.Constructor ||
+                node.kind === SyntaxKind.ConstructSignature) {
                 checkGrammarFunctionLikeDeclaration(<FunctionLikeDeclaration>node);
             }
 
@@ -8324,9 +8376,9 @@ module ts {
         function checkFunctionDeclaration(node: FunctionDeclaration): void {
             if (produceDiagnostics) {
                 checkFunctionLikeDeclaration(node) ||
-                    checkGrammarDisallowedModifiersInBlockOrObjectLiteralExpression(node) ||
-                    checkGrammarFunctionName(node.name) ||
-                    checkGrammarForGenerator(node);
+                checkGrammarDisallowedModifiersInBlockOrObjectLiteralExpression(node) ||
+                checkGrammarFunctionName(node.name) ||
+                checkGrammarForGenerator(node);
 
                 checkCollisionWithCapturedSuperVariable(node, node.name);
                 checkCollisionWithCapturedThisVariable(node, node.name);
@@ -8433,7 +8485,7 @@ module ts {
 
             return true;
         }
-        
+
         function checkCollisionWithCapturedThisVariable(node: Node, name: Identifier): void {
             if (needCollisionCheckForIdentifier(node, name, "_this")) {
                 potentialThisCollisions.push(node);
@@ -8443,7 +8495,7 @@ module ts {
         // this function will run after checking the source file so 'CaptureThis' is correct for all nodes
         function checkIfThisIsCapturedInEnclosingScope(node: Node): void {
             var current = node;
-            while (current) {                
+            while (current) {
                 if (getNodeCheckFlags(current) & NodeCheckFlags.CaptureThis) {
                     var isDeclaration = node.kind !== SyntaxKind.Identifier;
                     if (isDeclaration) {
@@ -8544,8 +8596,8 @@ module ts {
                             var namesShareScope =
                                 container &&
                                 (container.kind === SyntaxKind.Block && isAnyFunction(container.parent) ||
-                                (container.kind === SyntaxKind.ModuleBlock && container.kind === SyntaxKind.ModuleDeclaration) ||
-                                 container.kind === SyntaxKind.SourceFile);
+                                    (container.kind === SyntaxKind.ModuleBlock && container.kind === SyntaxKind.ModuleDeclaration) ||
+                                    container.kind === SyntaxKind.SourceFile);
 
                             // here we know that function scoped variable is shadowed by block scoped one
                             // if they are defined in the same scope - binder has already reported redeclaration error
@@ -8751,9 +8803,50 @@ module ts {
             checkSourceElement(node.statement);
         }
 
-        function checkForOfStatement(node: ForOfStatement) {
-            // TODO: not yet implemented
-            checkGrammarForOfStatement(node);
+        function checkForOfStatement(node: ForOfStatement): void {
+            if (languageVersion < ScriptTarget.ES6) {
+                grammarErrorOnFirstToken(node, Diagnostics.for_of_statements_are_only_available_when_targeting_ECMAScript_6_or_higher);
+                return;
+            }
+            
+            checkGrammarForInOrForOfStatement(node)
+
+            // Check the LHS and RHS
+            // If the LHS is a declaration, just check it as a variable declaration, which will in turn check the RHS
+            // via getTypeForVariableDeclarationInForOfStatement.
+            // If the LHS is an expression, check the LHS, as a destructuring assignment or as a reference.
+            // Then check that the RHS is assignable to it.
+            if (node.initializer.kind === SyntaxKind.VariableDeclarationList) {
+                checkForInOrForOfVariableDeclaration(node);
+            }
+            else {
+                var varExpr = <Expression>node.initializer;
+                var rightType = checkExpression(node.expression);
+                var iteratedType = checkIteratedType(rightType, node.expression);
+                
+                // There may be a destructuring assignment on the left side
+                if (varExpr.kind === SyntaxKind.ArrayLiteralExpression || varExpr.kind === SyntaxKind.ObjectLiteralExpression) {
+                    // iteratedType may be undefined. In this case, we still want to check the structure of
+                    // varExpr, in particular making sure it's a valid LeftHandSideExpression. But we'd like
+                    // to short circuit the type relation checking as much as possible, so we pass the unknownType.
+                    checkDestructuringAssignment(varExpr, iteratedType || unknownType);
+                }
+                else {
+                    var leftType = checkExpression(varExpr);
+                    checkReferenceExpression(varExpr, /*invalidReferenceMessage*/ Diagnostics.Invalid_left_hand_side_in_for_of_statement,
+                        /*constantVariableMessage*/ Diagnostics.The_left_hand_side_of_a_for_of_statement_cannot_be_a_previously_defined_constant);
+                
+                    // iteratedType will be undefined if the rightType was missing properties/signatures
+                    // required to get its iteratedType (like [Symbol.iterator] or next). This may be
+                    // because we accessed properties from anyType, or it may have led to an error inside
+                    // getIteratedType.
+                    if (iteratedType) {
+                        checkTypeAssignableTo(iteratedType, leftType, varExpr, /*headMessage*/ undefined);
+                    }
+                }
+            }
+
+            checkSourceElement(node.statement);
         }
 
         function checkForInStatement(node: ForInStatement) {
@@ -8766,11 +8859,12 @@ module ts {
             //   VarDecl must be a variable declaration without a type annotation that declares a variable of type Any,
             //   and Expr must be an expression of type Any, an object type, or a type parameter type.                        
             if (node.initializer.kind === SyntaxKind.VariableDeclarationList) {
-                var variableDeclarationList = <VariableDeclarationList>node.initializer;
-                if (variableDeclarationList.declarations.length >= 1) {
-                    var decl = variableDeclarationList.declarations[0];
-                    checkVariableDeclaration(decl);
+                var variable = (<VariableDeclarationList>node.initializer).declarations[0];
+                if (variable && isBindingPattern(variable.name)) {
+                    error(variable.name, Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_be_a_destructuring_pattern);
                 }
+                
+                checkForInOrForOfVariableDeclaration(node);
             }
             else {
                 // In a 'for-in' statement of the form
@@ -8778,26 +8872,148 @@ module ts {
                 //   Var must be an expression classified as a reference of type Any or the String primitive type,
                 //   and Expr must be an expression of type Any, an object type, or a type parameter type.
                 var varExpr = <Expression>node.initializer;
-                var exprType = checkExpression(varExpr);
-                if (!allConstituentTypesHaveKind(exprType, TypeFlags.Any | TypeFlags.StringLike)) {
+                var leftType = checkExpression(varExpr);
+                if (varExpr.kind === SyntaxKind.ArrayLiteralExpression || varExpr.kind === SyntaxKind.ObjectLiteralExpression) {
+                    error(varExpr, Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_be_a_destructuring_pattern);
+                }
+                else if (!allConstituentTypesHaveKind(leftType, TypeFlags.Any | TypeFlags.StringLike)) {
                     error(varExpr, Diagnostics.The_left_hand_side_of_a_for_in_statement_must_be_of_type_string_or_any);
                 }
                 else {
                     // run check only former check succeeded to avoid cascading errors
-                    checkReferenceExpression(varExpr, Diagnostics.Invalid_left_hand_side_in_for_in_statement, Diagnostics.Left_hand_side_of_assignment_expression_cannot_be_a_constant);
+                    checkReferenceExpression(varExpr, Diagnostics.Invalid_left_hand_side_in_for_in_statement, Diagnostics.The_left_hand_side_of_a_for_in_statement_cannot_be_a_previously_defined_constant);
                 }
             }
 
-            var exprType = checkExpression(node.expression);
+            var rightType = checkExpression(node.expression);
             // unknownType is returned i.e. if node.expression is identifier whose name cannot be resolved
             // in this case error about missing name is already reported - do not report extra one
-            if (!allConstituentTypesHaveKind(exprType, TypeFlags.Any | TypeFlags.ObjectType | TypeFlags.TypeParameter)) {
+            if (!allConstituentTypesHaveKind(rightType, TypeFlags.Any | TypeFlags.ObjectType | TypeFlags.TypeParameter)) {
                 error(node.expression, Diagnostics.The_right_hand_side_of_a_for_in_statement_must_be_of_type_any_an_object_type_or_a_type_parameter);
             }
 
             checkSourceElement(node.statement);
         }
 
+        function checkForInOrForOfVariableDeclaration(iterationStatement: ForInStatement | ForOfStatement): void {
+            var variableDeclarationList = <VariableDeclarationList>iterationStatement.initializer;
+            // checkGrammarForInOrForOfStatement will check that there is exactly one declaration.
+            if (variableDeclarationList.declarations.length >= 1) {
+                var decl = variableDeclarationList.declarations[0];
+                checkVariableDeclaration(decl);
+            }
+        }
+
+        function getTypeForVariableDeclarationInForOfStatement(forOfStatement: ForOfStatement): Type {
+            // Temporarily return 'any' below ES6
+            if (languageVersion < ScriptTarget.ES6) {
+                return anyType;
+            }
+
+            // iteratedType will be undefined if the for-of expression type was missing properties/signatures
+            // required to get its iteratedType (like [Symbol.iterator] or next). This may be
+            // because we accessed properties from anyType, or it may have led to an error inside
+            // getIteratedType.
+            var expressionType = getTypeOfExpression(forOfStatement.expression);
+            return checkIteratedType(expressionType, forOfStatement.expression) || anyType;
+        }
+
+        /**
+         * When expressionForError is undefined, it means we should not report any errors.
+         */
+        function checkIteratedType(iterable: Type, expressionForError: Expression): Type {
+            Debug.assert(languageVersion >= ScriptTarget.ES6);
+            var iteratedType = getIteratedType(iterable, expressionForError);
+            // Now even though we have extracted the iteratedType, we will have to validate that the type
+            // passed in is actually an Iterable.
+            if (expressionForError && iteratedType) {
+                var completeIterableType = globalIterableType !== emptyObjectType
+                    ? createTypeReference(<GenericType>globalIterableType, [iteratedType])
+                    : emptyObjectType;
+                checkTypeAssignableTo(iterable, completeIterableType, expressionForError);
+            }
+
+            return iteratedType;
+            
+            function getIteratedType(iterable: Type, expressionForError: Expression) {
+                // We want to treat type as an iterable, and get the type it is an iterable of. The iterable
+                // must have the following structure (annotated with the names of the variables below):
+                //
+                // { // iterable
+                //     [Symbol.iterator]: { // iteratorFunction
+                //         (): { // iterator
+                //             next: { // iteratorNextFunction
+                //                 (): { // iteratorNextResult
+                //                     value: T // iteratorNextValue
+                //                 }
+                //             }
+                //         }
+                //     }
+                // }
+                //
+                // T is the type we are after. At every level that involves analyzing return types
+                // of signatures, we union the return types of all the signatures.
+                //
+                // Another thing to note is that at any step of this process, we could run into a dead end,
+                // meaning either the property is missing, or we run into the anyType. If either of these things
+                // happens, we return undefined to signal that we could not find the iterated type. If a property
+                // is missing, and the previous step did not result in 'any', then we also give an error if the
+                // caller requested it. Then the caller can decide what to do in the case where there is no iterated
+                // type. This is different from returning anyType, because that would signify that we have matched the
+                // whole pattern and that T (above) is 'any'.
+                
+                if (allConstituentTypesHaveKind(iterable, TypeFlags.Any)) {
+                    return undefined;
+                }
+
+                var iteratorFunction = getTypeOfPropertyOfType(iterable, getPropertyNameForKnownSymbolName("iterator"));
+                if (iteratorFunction && allConstituentTypesHaveKind(iteratorFunction, TypeFlags.Any)) {
+                    return undefined;
+                }
+
+                var iteratorFunctionSignatures = iteratorFunction ? getSignaturesOfType(iteratorFunction, SignatureKind.Call) : emptyArray;
+                if (iteratorFunctionSignatures.length === 0) {
+                    if (expressionForError) {
+                        error(expressionForError, Diagnostics.The_right_hand_side_of_a_for_of_statement_must_have_a_Symbol_iterator_method_that_returns_an_iterator);
+                    }
+                    return undefined;
+                }
+
+                var iterator = getUnionType(map(iteratorFunctionSignatures, getReturnTypeOfSignature));
+                if (allConstituentTypesHaveKind(iterator, TypeFlags.Any)) {
+                    return undefined;
+                }
+
+                var iteratorNextFunction = getTypeOfPropertyOfType(iterator, "next");
+                if (iteratorNextFunction && allConstituentTypesHaveKind(iteratorNextFunction, TypeFlags.Any)) {
+                    return undefined;
+                }
+
+                var iteratorNextFunctionSignatures = iteratorNextFunction ? getSignaturesOfType(iteratorNextFunction, SignatureKind.Call) : emptyArray;
+                if (iteratorNextFunctionSignatures.length === 0) {
+                    if (expressionForError) {
+                        error(expressionForError, Diagnostics.The_iterator_returned_by_the_right_hand_side_of_a_for_of_statement_must_have_a_next_method);
+                    }
+                    return undefined;
+                }
+
+                var iteratorNextResult = getUnionType(map(iteratorNextFunctionSignatures, getReturnTypeOfSignature));
+                if (allConstituentTypesHaveKind(iteratorNextResult, TypeFlags.Any)) {
+                    return undefined;
+                }
+
+                var iteratorNextValue = getTypeOfPropertyOfType(iteratorNextResult, "value");
+                if (!iteratorNextValue) {
+                    if (expressionForError) {
+                        error(expressionForError, Diagnostics.The_type_returned_by_the_next_method_of_an_iterator_must_have_a_value_property);
+                    }
+                    return undefined;
+                }
+                
+                return iteratorNextValue;
+            }
+        }
+
         function checkBreakOrContinueStatement(node: BreakOrContinueStatement) {
             // Grammar checking
             checkGrammarStatementInAmbientContext(node) || checkGrammarBreakOrContinueStatement(node);
@@ -8931,18 +9147,29 @@ module ts {
             var catchClause = node.catchClause;
             if (catchClause) {
                 // Grammar checking
-                if (catchClause.type) {
-                    var sourceFile = getSourceFileOfNode(node);
-                    var colonStart = skipTrivia(sourceFile.text, catchClause.name.end);
-                    grammarErrorAtPos(sourceFile, colonStart, ":".length, Diagnostics.Catch_clause_parameter_cannot_have_a_type_annotation);
+                if (catchClause.variableDeclaration) {
+                    if (catchClause.variableDeclaration.name.kind !== SyntaxKind.Identifier) {
+                        grammarErrorOnFirstToken(catchClause.variableDeclaration.name, Diagnostics.Catch_clause_variable_name_must_be_an_identifier);
+                    }
+                    else if (catchClause.variableDeclaration.type) {
+                        grammarErrorOnFirstToken(catchClause.variableDeclaration.type, Diagnostics.Catch_clause_variable_cannot_have_a_type_annotation);
+                    }
+                    else if (catchClause.variableDeclaration.initializer) {
+                        grammarErrorOnFirstToken(catchClause.variableDeclaration.initializer, Diagnostics.Catch_clause_variable_cannot_have_an_initializer);
+                    }
+                    else {
+                        // It is a SyntaxError if a TryStatement with a Catch occurs within strict code and the Identifier of the
+                        // Catch production is eval or arguments
+                        checkGrammarEvalOrArgumentsInStrictMode(node, <Identifier>catchClause.variableDeclaration.name);
+                    }
                 }
-                // It is a SyntaxError if a TryStatement with a Catch occurs within strict code and the Identifier of the
-                // Catch production is eval or arguments
-                checkGrammarEvalOrArgumentsInStrictMode(node, catchClause.name);
 
                 checkBlock(catchClause.block);
             }
-            if (node.finallyBlock) checkBlock(node.finallyBlock);
+
+            if (node.finallyBlock) {
+                checkBlock(node.finallyBlock);
+            }
         }
 
         function checkIndexConstraints(type: Type) {
@@ -10054,11 +10281,6 @@ module ts {
                             copySymbol(location.symbol, meaning);
                         }
                         break;
-                    case SyntaxKind.CatchClause:
-                        if ((<CatchClause>location).name.text) {
-                            copySymbol(location.symbol, meaning);
-                        }
-                        break;
                 }
                 memberFlags = location.flags;
                 location = location.parent;
@@ -10195,7 +10417,7 @@ module ts {
         }
 
         function getSymbolOfEntityNameOrPropertyAccessExpression(entityName: EntityName | PropertyAccessExpression): Symbol {
-            if (isDeclarationOrFunctionExpressionOrCatchVariableName(entityName)) {
+            if (isDeclarationName(entityName)) {
                 return getSymbolOfNode(entityName.parent);
             }
 
@@ -10260,7 +10482,7 @@ module ts {
                 return undefined;
             }
 
-            if (isDeclarationOrFunctionExpressionOrCatchVariableName(node)) {
+            if (isDeclarationName(node)) {
                 // This is a declaration, call getSymbolOfNode
                 return getSymbolOfNode(node.parent);
             }
@@ -10356,7 +10578,7 @@ module ts {
                 return getTypeOfSymbol(symbol);
             }
 
-            if (isDeclarationOrFunctionExpressionOrCatchVariableName(node)) {
+            if (isDeclarationName(node)) {
                 var symbol = getSymbolInfo(node);
                 return symbol && getTypeOfSymbol(symbol);
             }
@@ -10472,25 +10694,8 @@ module ts {
             }
 
             function makeUniqueName(baseName: string): string {
-                // First try '_name'
-                if (baseName.charCodeAt(0) !== CharacterCodes._) {
-                    var baseName = "_" + baseName;
-                    if (!isExistingName(baseName)) {
-                        return generatedNames[baseName] = baseName;
-                    }
-                }
-                // Find the first unique '_name_n', where n is a positive number
-                if (baseName.charCodeAt(baseName.length - 1) !== CharacterCodes._) {
-                    baseName += "_";
-                }
-                var i = 1;
-                while (true) {
-                    name = baseName + i;
-                    if (!isExistingName(name)) {
-                        return generatedNames[name] = name;
-                    }
-                    i++;
-                }
+                var name = generateUniqueName(baseName, isExistingName);
+                return generatedNames[name] = name;
             }
 
             function assignGeneratedName(node: Node, name: string) {
@@ -10691,6 +10896,46 @@ module ts {
                 !hasProperty(getGeneratedNamesForSourceFile(getSourceFile(location)), name);
         }
 
+        function getBlockScopedVariableId(n: Identifier): number {
+            Debug.assert(!nodeIsSynthesized(n));
+
+            // ignore name parts of property access expressions
+            if (n.parent.kind === SyntaxKind.PropertyAccessExpression &&
+                (<PropertyAccessExpression>n.parent).name === n) {
+                return undefined;
+            }
+
+            // ignore property names in object binding patterns
+            if (n.parent.kind === SyntaxKind.BindingElement &&
+                (<BindingElement>n.parent).propertyName === n) {
+                return undefined;
+            }
+
+            // for names in variable declarations and binding elements try to short circuit and fetch symbol from the node
+            var declarationSymbol: Symbol =
+                (n.parent.kind === SyntaxKind.VariableDeclaration && (<VariableDeclaration>n.parent).name === n) ||
+                 n.parent.kind === SyntaxKind.BindingElement
+                    ? getSymbolOfNode(n.parent)
+                    : undefined;
+
+            var symbol = declarationSymbol ||
+                getNodeLinks(n).resolvedSymbol ||
+                resolveName(n, n.text, SymbolFlags.BlockScopedVariable | SymbolFlags.Import, /*nodeNotFoundMessage*/ undefined, /*nameArg*/ undefined);
+            
+            var isLetOrConst =
+                symbol &&
+                (symbol.flags & SymbolFlags.BlockScopedVariable) &&
+                symbol.valueDeclaration.parent.kind !== SyntaxKind.CatchClause;
+
+            if (isLetOrConst) {
+                // side-effect of calling this method:
+                //   assign id to symbol if it was not yet set
+                getSymbolLinks(symbol);
+                return symbol.id;
+            }
+            return undefined;
+        }
+
         function createResolver(): EmitResolver {
             return {
                 getGeneratedNameForNode,
@@ -10707,6 +10952,7 @@ module ts {
                 isEntityNameVisible,
                 getConstantValue,
                 isUnknownIdentifier,
+                getBlockScopedVariableId,
             };
         }
 
@@ -10730,7 +10976,7 @@ module ts {
             globals[undefinedSymbol.name] = undefinedSymbol;
             // Initialize special types
             globalArraySymbol = getGlobalTypeSymbol("Array");
-            globalArrayType = getTypeOfGlobalSymbol(globalArraySymbol, 1);
+            globalArrayType = getTypeOfGlobalSymbol(globalArraySymbol, /*arity*/ 1);
             globalObjectType = getGlobalType("Object");
             globalFunctionType = getGlobalType("Function");
             globalStringType = getGlobalType("String");
@@ -10744,6 +10990,7 @@ module ts {
                 globalTemplateStringsArrayType = getGlobalType("TemplateStringsArray");
                 globalESSymbolType = getGlobalType("Symbol");
                 globalESSymbolConstructorSymbol = getGlobalValueSymbol("Symbol");
+                globalIterableType = getGlobalType("Iterable", /*arity*/ 1);
             }
             else {
                 globalTemplateStringsArrayType = unknownType;
@@ -11250,16 +11497,6 @@ module ts {
             return false;
         }
 
-        function checkGrammarForOfStatement(forOfStatement: ForOfStatement): boolean {
-            // Temporarily disallow for-of statements until type check work is complete.
-            return grammarErrorOnFirstToken(forOfStatement, Diagnostics.for_of_statements_are_not_currently_supported);
-            if (languageVersion < ScriptTarget.ES6) {
-                return grammarErrorOnFirstToken(forOfStatement, Diagnostics.for_of_statements_are_only_available_when_targeting_ECMAScript_6_or_higher);
-            }
-
-            return checkGrammarForInOrForOfStatement(forOfStatement);
-        }
-
         function checkGrammarAccessor(accessor: MethodDeclaration): boolean {
             var kind = accessor.kind;
             if (languageVersion < ScriptTarget.ES5) {
@@ -11434,17 +11671,19 @@ module ts {
         }
 
         function checkGrammarVariableDeclaration(node: VariableDeclaration) {
-            if (isInAmbientContext(node)) {
-                if (isBindingPattern(node.name)) {
-                    return grammarErrorOnNode(node, Diagnostics.Destructuring_declarations_are_not_allowed_in_ambient_contexts);
+            if (node.parent.parent.kind !== SyntaxKind.ForInStatement && node.parent.parent.kind !== SyntaxKind.ForOfStatement) {
+                if (isInAmbientContext(node)) {
+                    if (isBindingPattern(node.name)) {
+                        return grammarErrorOnNode(node, Diagnostics.Destructuring_declarations_are_not_allowed_in_ambient_contexts);
+                    }
+                    if (node.initializer) {
+                        // Error on equals token which immediate precedes the initializer
+                        var equalsTokenLength = "=".length;
+                        return grammarErrorAtPos(getSourceFileOfNode(node), node.initializer.pos - equalsTokenLength,
+                            equalsTokenLength, Diagnostics.Initializers_are_not_allowed_in_ambient_contexts);
+                    }
                 }
-                if (node.initializer) {
-                    // Error on equals token which immediate precedes the initializer
-                    return grammarErrorAtPos(getSourceFileOfNode(node), node.initializer.pos - 1, 1, Diagnostics.Initializers_are_not_allowed_in_ambient_contexts);
-                }
-            }
-            else {
-                if (!node.initializer) {
+                else if (!node.initializer) {
                     if (isBindingPattern(node.name) && !isBindingPattern(node.parent)) {
                         return grammarErrorOnNode(node, Diagnostics.A_destructuring_declaration_must_have_an_initializer);
                     }
@@ -11490,15 +11729,6 @@ module ts {
             if (!declarationList.declarations.length) {
                 return grammarErrorAtPos(getSourceFileOfNode(declarationList), declarations.pos, declarations.end - declarations.pos, Diagnostics.Variable_declaration_list_cannot_be_empty);
             }
-
-            if (languageVersion < ScriptTarget.ES6) {
-                if (isLet(declarationList)) {
-                    return grammarErrorOnFirstToken(declarationList, Diagnostics.let_declarations_are_only_available_when_targeting_ECMAScript_6_and_higher);
-                }
-                else if (isConst(declarationList)) {
-                    return grammarErrorOnFirstToken(declarationList, Diagnostics.const_declarations_are_only_available_when_targeting_ECMAScript_6_and_higher);
-                }
-            }
         }
 
         function allowLetAndConstDeclarations(parent: Node): boolean {
@@ -11621,10 +11851,13 @@ module ts {
             }
         }
 
-        function checkGrammarEvalOrArgumentsInStrictMode(contextNode: Node, identifier: Identifier): boolean {
-            if (contextNode && (contextNode.parserContextFlags & ParserContextFlags.StrictMode) && isEvalOrArgumentsIdentifier(identifier)) {
-                var name = declarationNameToString(identifier);
-                return grammarErrorOnNode(identifier, Diagnostics.Invalid_use_of_0_in_strict_mode, name);
+        function checkGrammarEvalOrArgumentsInStrictMode(contextNode: Node, name: Node): boolean {
+            if (name && name.kind === SyntaxKind.Identifier) {
+                var identifier = <Identifier>name;
+                if (contextNode && (contextNode.parserContextFlags & ParserContextFlags.StrictMode) && isEvalOrArgumentsIdentifier(identifier)) {
+                    var nameText = declarationNameToString(identifier);
+                    return grammarErrorOnNode(identifier, Diagnostics.Invalid_use_of_0_in_strict_mode, nameText);
+                }
             }
         }
 

src/compiler/diagnosticInformationMap.generated.ts

@@ -9,7 +9,6 @@ module ts {
         Trailing_comma_not_allowed: { code: 1009, category: DiagnosticCategory.Error, key: "Trailing comma not allowed." },
         Asterisk_Slash_expected: { code: 1010, category: DiagnosticCategory.Error, key: "'*/' expected." },
         Unexpected_token: { code: 1012, category: DiagnosticCategory.Error, key: "Unexpected token." },
-        Catch_clause_parameter_cannot_have_a_type_annotation: { code: 1013, category: DiagnosticCategory.Error, key: "Catch clause parameter cannot have a type annotation." },
         A_rest_parameter_must_be_last_in_a_parameter_list: { code: 1014, category: DiagnosticCategory.Error, key: "A rest parameter must be last in a parameter list." },
         Parameter_cannot_have_question_mark_and_initializer: { code: 1015, category: DiagnosticCategory.Error, key: "Parameter cannot have question mark and initializer." },
         A_required_parameter_cannot_follow_an_optional_parameter: { code: 1016, category: DiagnosticCategory.Error, key: "A required parameter cannot follow an optional parameter." },
@@ -117,7 +116,6 @@ module ts {
         const_declarations_must_be_initialized: { code: 1155, category: DiagnosticCategory.Error, key: "'const' declarations must be initialized" },
         const_declarations_can_only_be_declared_inside_a_block: { code: 1156, category: DiagnosticCategory.Error, key: "'const' declarations can only be declared inside a block." },
         let_declarations_can_only_be_declared_inside_a_block: { code: 1157, category: DiagnosticCategory.Error, key: "'let' declarations can only be declared inside a block." },
-        Tagged_templates_are_only_available_when_targeting_ECMAScript_6_and_higher: { code: 1159, category: DiagnosticCategory.Error, key: "Tagged templates are only available when targeting ECMAScript 6 and higher." },
         Unterminated_template_literal: { code: 1160, category: DiagnosticCategory.Error, key: "Unterminated template literal." },
         Unterminated_regular_expression_literal: { code: 1161, category: DiagnosticCategory.Error, key: "Unterminated regular expression literal." },
         An_object_member_cannot_be_declared_optional: { code: 1162, category: DiagnosticCategory.Error, key: "An object member cannot be declared optional." },
@@ -154,6 +152,9 @@ module ts {
         External_module_0_has_no_default_export_or_export_assignment: { code: 1192, category: DiagnosticCategory.Error, key: "External module '{0}' has no default export or export assignment." },
         An_export_declaration_cannot_have_modifiers: { code: 1193, category: DiagnosticCategory.Error, key: "An export declaration cannot have modifiers." },
         Export_declarations_are_not_permitted_in_an_internal_module: { code: 1194, category: DiagnosticCategory.Error, key: "Export declarations are not permitted in an internal module." },
+        Catch_clause_variable_name_must_be_an_identifier: { code: 1195, category: DiagnosticCategory.Error, key: "Catch clause variable name must be an identifier." },
+        Catch_clause_variable_cannot_have_a_type_annotation: { code: 1196, category: DiagnosticCategory.Error, key: "Catch clause variable cannot have a type annotation." },
+        Catch_clause_variable_cannot_have_an_initializer: { code: 1197, category: DiagnosticCategory.Error, key: "Catch clause variable cannot have an initializer." },
         Duplicate_identifier_0: { code: 2300, category: DiagnosticCategory.Error, key: "Duplicate identifier '{0}'." },
         Initializer_of_instance_member_variable_0_cannot_reference_identifier_1_declared_in_the_constructor: { code: 2301, category: DiagnosticCategory.Error, key: "Initializer of instance member variable '{0}' cannot reference identifier '{1}' declared in the constructor." },
         Static_members_cannot_reference_class_type_parameters: { code: 2302, category: DiagnosticCategory.Error, key: "Static members cannot reference class type parameters." },
@@ -327,6 +328,13 @@ module ts {
         for_of_statements_are_only_available_when_targeting_ECMAScript_6_or_higher: { code: 2482, category: DiagnosticCategory.Error, key: "'for...of' statements are only available when targeting ECMAScript 6 or higher." },
         The_left_hand_side_of_a_for_of_statement_cannot_use_a_type_annotation: { code: 2483, category: DiagnosticCategory.Error, key: "The left-hand side of a 'for...of' statement cannot use a type annotation." },
         Export_declaration_conflicts_with_exported_declaration_of_0: { code: 2484, category: DiagnosticCategory.Error, key: "Export declaration conflicts with exported declaration of '{0}'" },
+        The_left_hand_side_of_a_for_of_statement_cannot_be_a_previously_defined_constant: { code: 2485, category: DiagnosticCategory.Error, key: "The left-hand side of a 'for...of' statement cannot be a previously defined constant." },
+        The_left_hand_side_of_a_for_in_statement_cannot_be_a_previously_defined_constant: { code: 2486, category: DiagnosticCategory.Error, key: "The left-hand side of a 'for...in' statement cannot be a previously defined constant." },
+        Invalid_left_hand_side_in_for_of_statement: { code: 2487, category: DiagnosticCategory.Error, key: "Invalid left-hand side in 'for...of' statement." },
+        The_right_hand_side_of_a_for_of_statement_must_have_a_Symbol_iterator_method_that_returns_an_iterator: { code: 2488, category: DiagnosticCategory.Error, key: "The right-hand side of a 'for...of' statement must have a '[Symbol.iterator]()' method that returns an iterator." },
+        The_iterator_returned_by_the_right_hand_side_of_a_for_of_statement_must_have_a_next_method: { code: 2489, category: DiagnosticCategory.Error, key: "The iterator returned by the right-hand side of a 'for...of' statement must have a 'next()' method." },
+        The_type_returned_by_the_next_method_of_an_iterator_must_have_a_value_property: { code: 2490, category: DiagnosticCategory.Error, key: "The type returned by the 'next()' method of an iterator must have a 'value' property." },
+        The_left_hand_side_of_a_for_in_statement_cannot_be_a_destructuring_pattern: { code: 2491, category: DiagnosticCategory.Error, key: "The left-hand side of a 'for...in' statement cannot be a destructuring pattern." },
         Import_declaration_0_is_using_private_name_1: { code: 4000, category: DiagnosticCategory.Error, key: "Import declaration '{0}' is using private name '{1}'." },
         Type_parameter_0_of_exported_class_has_or_is_using_private_name_1: { code: 4002, category: DiagnosticCategory.Error, key: "Type parameter '{0}' of exported class has or is using private name '{1}'." },
         Type_parameter_0_of_exported_interface_has_or_is_using_private_name_1: { code: 4004, category: DiagnosticCategory.Error, key: "Type parameter '{0}' of exported interface has or is using private name '{1}'." },
@@ -396,6 +404,7 @@ module ts {
         Parameter_0_of_exported_function_has_or_is_using_name_1_from_private_module_2: { code: 4077, category: DiagnosticCategory.Error, key: "Parameter '{0}' of exported function has or is using name '{1}' from private module '{2}'." },
         Parameter_0_of_exported_function_has_or_is_using_private_name_1: { code: 4078, category: DiagnosticCategory.Error, key: "Parameter '{0}' of exported function has or is using private name '{1}'." },
         Exported_type_alias_0_has_or_is_using_private_name_1: { code: 4081, category: DiagnosticCategory.Error, key: "Exported type alias '{0}' has or is using private name '{1}'." },
+        Loop_contains_block_scoped_variable_0_referenced_by_a_function_in_the_loop_This_is_only_supported_in_ECMAScript_6_or_higher: { code: 4091, category: DiagnosticCategory.Error, key: "Loop contains block-scoped variable '{0}' referenced by a function in the loop. This is only supported in ECMAScript 6 or higher." },
         The_current_host_does_not_support_the_0_option: { code: 5001, category: DiagnosticCategory.Error, key: "The current host does not support the '{0}' option." },
         Cannot_find_the_common_subdirectory_path_for_the_input_files: { code: 5009, category: DiagnosticCategory.Error, key: "Cannot find the common subdirectory path for the input files." },
         Cannot_read_file_0_Colon_1: { code: 5012, category: DiagnosticCategory.Error, key: "Cannot read file '{0}': {1}" },
@@ -472,6 +481,5 @@ module ts {
         yield_expressions_are_not_currently_supported: { code: 9000, category: DiagnosticCategory.Error, key: "'yield' expressions are not currently supported." },
         Generators_are_not_currently_supported: { code: 9001, category: DiagnosticCategory.Error, key: "Generators are not currently supported." },
         The_arguments_object_cannot_be_referenced_in_an_arrow_function_Consider_using_a_standard_function_expression: { code: 9002, category: DiagnosticCategory.Error, key: "The 'arguments' object cannot be referenced in an arrow function. Consider using a standard function expression." },
-        for_of_statements_are_not_currently_supported: { code: 9003, category: DiagnosticCategory.Error, key: "'for...of' statements are not currently supported." },
     };
 }

src/compiler/diagnosticMessages.json

@@ -27,10 +27,6 @@
         "category": "Error",
         "code": 1012
     },
-    "Catch clause parameter cannot have a type annotation.": {
-        "category": "Error",
-        "code": 1013
-    },
     "A rest parameter must be last in a parameter list.": {
         "category": "Error",
         "code": 1014
@@ -459,10 +455,6 @@
         "category": "Error",
         "code": 1157
     },
-    "Tagged templates are only available when targeting ECMAScript 6 and higher.": {
-        "category": "Error",
-        "code": 1159
-    },
     "Unterminated template literal.": {
         "category": "Error",
         "code": 1160
@@ -607,6 +599,18 @@
         "category": "Error",
         "code": 1194
     },
+    "Catch clause variable name must be an identifier.": {
+        "category": "Error",
+        "code": 1195
+    },
+    "Catch clause variable cannot have a type annotation.": {
+        "category": "Error",
+        "code": 1196
+    },
+    "Catch clause variable cannot have an initializer.": {
+        "category": "Error",
+        "code": 1197
+    },
 
     "Duplicate identifier '{0}'.": {
         "category": "Error",
@@ -1300,6 +1304,34 @@
         "category": "Error",
         "code": 2484
     },
+    "The left-hand side of a 'for...of' statement cannot be a previously defined constant.": {
+        "category": "Error",
+        "code": 2485
+    },
+    "The left-hand side of a 'for...in' statement cannot be a previously defined constant.": {
+        "category": "Error",
+        "code": 2486
+    },
+    "Invalid left-hand side in 'for...of' statement.": {
+        "category": "Error",
+        "code": 2487
+    },
+    "The right-hand side of a 'for...of' statement must have a '[Symbol.iterator]()' method that returns an iterator.": {
+        "category": "Error",
+        "code": 2488
+    },
+    "The iterator returned by the right-hand side of a 'for...of' statement must have a 'next()' method.": {
+        "category": "Error",
+        "code": 2489
+    },
+    "The type returned by the 'next()' method of an iterator must have a 'value' property.": {
+        "category": "Error",
+        "code": 2490
+    },
+    "The left-hand side of a 'for...in' statement cannot be a destructuring pattern.": {
+        "category": "Error",
+        "code": 2491
+    },
 
     "Import declaration '{0}' is using private name '{1}'.": {
         "category": "Error",
@@ -1576,7 +1608,11 @@
     "Exported type alias '{0}' has or is using private name '{1}'.": {
         "category": "Error",
         "code": 4081
-    },
+    },
+    "Loop contains block-scoped variable '{0}' referenced by a function in the loop. This is only supported in ECMAScript 6 or higher.": {
+        "category": "Error",
+        "code": 4091
+    },
     "The current host does not support the '{0}' option.": {
         "category": "Error",
         "code": 5001
@@ -1881,9 +1917,5 @@
     "The 'arguments' object cannot be referenced in an arrow function. Consider using a standard function expression.": {
         "category": "Error",
         "code": 9002
-    },
-    "'for...of' statements are not currently supported.": {
-        "category": "Error",
-        "code": 9003
     }
 }

src/compiler/emitter.ts

@@ -28,9 +28,10 @@ module ts {
         typeName?: DeclarationName;
     }
 
-    interface SynthesizedNode extends Node {
-        leadingCommentRanges?: CommentRange[];
-        trailingCommentRanges?: CommentRange[];
+    // represents one LexicalEnvironment frame to store unique generated names
+    interface ScopeFrame {
+        names: Map<string>;
+        previous: ScopeFrame;
     }
 
     type GetSymbolAccessibilityDiagnostic = (symbolAccesibilityResult: SymbolAccessiblityResult) => SymbolAccessibilityDiagnostic;
@@ -369,7 +370,6 @@ module ts {
         var enclosingDeclaration: Node;
         var currentSourceFile: SourceFile;
         var reportedDeclarationError = false;
-
         var emitJsDocComments = compilerOptions.removeComments ? function (declaration: Node) { } : writeJsDocComments;
         var emit = compilerOptions.stripInternal ? stripInternal : emitNode;
 
@@ -1574,6 +1574,11 @@ module ts {
 
             var currentSourceFile: SourceFile;
 
+            var lastFrame: ScopeFrame;
+            var currentScopeNames: Map<string>;
+
+            var generatedBlockScopeNames: string[];
+
             var extendsEmitted = false;
             var tempCount = 0;
             var tempVariables: Identifier[];
@@ -1648,6 +1653,50 @@ module ts {
             writeEmittedFiles(writer.getText(), /*writeByteOrderMark*/ compilerOptions.emitBOM);
             return;
 
+            // enters the new lexical environment
+            // return value should be passed to matching call to exitNameScope.
+            function enterNameScope(): boolean {
+                var names = currentScopeNames;
+                currentScopeNames = undefined;
+                if (names) {
+                    lastFrame = { names, previous: lastFrame };
+                    return true;
+                }
+                return false;
+            }
+
+            function exitNameScope(popFrame: boolean): void {
+                if (popFrame) {
+                    currentScopeNames = lastFrame.names;
+                    lastFrame = lastFrame.previous;
+                }
+                else {
+                    currentScopeNames = undefined;
+                }
+            }
+
+            function generateUniqueNameForLocation(location: Node, baseName: string): string {
+                var name: string
+                // first try to check if base name can be used as is
+                if (!isExistingName(location, baseName)) {
+                    name = baseName;
+                }
+                else {
+                    name = generateUniqueName(baseName, n => isExistingName(location, n));
+                }
+
+                if (!currentScopeNames) {
+                    currentScopeNames = {};
+                }
+
+                return currentScopeNames[name] = name;
+            }
+
+            function isExistingName(location: Node, name: string) {
+                return !resolver.isUnknownIdentifier(location, name) ||
+                    (currentScopeNames && hasProperty(currentScopeNames, name));
+            }
+
             function initializeEmitterWithSourceMaps() {
                 var sourceMapDir: string; // The directory in which sourcemap will be
 
@@ -2014,14 +2063,14 @@ module ts {
             function createTempVariable(location: Node, forLoopVariable?: boolean): Identifier {
                 var name = forLoopVariable ? "_i" : undefined;
                 while (true) {
-                    if (name && resolver.isUnknownIdentifier(location, name)) {
+                    if (name && !isExistingName(location, name)) {
                         break;
                     }
                     // _a .. _h, _j ... _z, _0, _1, ...
                     name = "_" + (tempCount < 25 ? String.fromCharCode(tempCount + (tempCount < 8 ? 0 : 1) + CharacterCodes.a) : tempCount - 25);
                     tempCount++;
                 }
-                var result = <Identifier>createNode(SyntaxKind.Identifier);
+                var result = <Identifier>createSynthesizedNode(SyntaxKind.Identifier);
                 result.text = name;
                 return result;
             }
@@ -2072,7 +2121,7 @@ module ts {
                 }
             }
 
-            function emitParenthesized(node: Node, parenthesized: boolean) {
+            function emitParenthesizedIf(node: Node, parenthesized: boolean) {
                 if (parenthesized) {
                     write("(");
                 }
@@ -2205,6 +2254,72 @@ module ts {
             function getTemplateLiteralAsStringLiteral(node: LiteralExpression): string {
                 return '"' + escapeString(node.text) + '"';
             }
+            
+            function emitDownlevelRawTemplateLiteral(node: LiteralExpression) {
+                // Find original source text, since we need to emit the raw strings of the tagged template.
+                // The raw strings contain the (escaped) strings of what the user wrote.
+                // Examples: `\n` is converted to "\\n", a template string with a newline to "\n".
+                var text = getSourceTextOfNodeFromSourceFile(currentSourceFile, node);
+                
+                // text contains the original source, it will also contain quotes ("`"), dolar signs and braces ("${" and "}"),
+                // thus we need to remove those characters.
+                // First template piece starts with "`", others with "}"
+                // Last template piece ends with "`", others with "${"
+                var isLast = node.kind === SyntaxKind.NoSubstitutionTemplateLiteral || node.kind === SyntaxKind.TemplateTail;
+                text = text.substring(1, text.length - (isLast ? 1 : 2));
+                
+                // Newline normalization:
+                // ES6 Spec 11.8.6.1 - Static Semantics of TV's and TRV's
+                // <CR><LF> and <CR> LineTerminatorSequences are normalized to <LF> for both TV and TRV.
+                text = text.replace(/\r\n?/g, "\n");
+                text = escapeString(text);
+                
+                write('"' + text + '"');
+            }
+            
+            function emitDownlevelTaggedTemplateArray(node: TaggedTemplateExpression, literalEmitter: (literal: LiteralExpression) => void) {
+                write("[");
+                if (node.template.kind === SyntaxKind.NoSubstitutionTemplateLiteral) {
+                    literalEmitter(<LiteralExpression>node.template);
+                }
+                else {
+                    literalEmitter((<TemplateExpression>node.template).head);
+                    forEach((<TemplateExpression>node.template).templateSpans, (child) => {
+                        write(", ");
+                        literalEmitter(child.literal);
+                    });
+                }
+                write("]");
+            }
+            
+            function emitDownlevelTaggedTemplate(node: TaggedTemplateExpression) {
+                var tempVariable = createAndRecordTempVariable(node);
+                write("(");
+                emit(tempVariable);
+                write(" = ");
+                emitDownlevelTaggedTemplateArray(node, emit);
+                write(", ");
+                
+                emit(tempVariable);
+                write(".raw = ");
+                emitDownlevelTaggedTemplateArray(node, emitDownlevelRawTemplateLiteral);
+                write(", ");
+                
+                emitParenthesizedIf(node.tag, needsParenthesisForPropertyAccessOrInvocation(node.tag));
+                write("(");
+                emit(tempVariable);
+                
+                // Now we emit the expressions
+                if (node.template.kind === SyntaxKind.TemplateExpression) {
+                    forEach((<TemplateExpression>node.template).templateSpans, templateSpan => {
+                        write(", ");
+                        var needsParens = templateSpan.expression.kind === SyntaxKind.BinaryExpression
+                            && (<BinaryExpression>templateSpan.expression).operatorToken.kind === SyntaxKind.CommaToken;
+                        emitParenthesizedIf(templateSpan.expression, needsParens);
+                    });
+                }
+                write("))");
+            }
 
             function emitTemplateExpression(node: TemplateExpression): void {
                 // In ES6 mode and above, we can simply emit each portion of a template in order, but in
@@ -2249,7 +2364,8 @@ module ts {
                         write(" + ");
                     }
 
-                    emitParenthesized(templateSpan.expression, needsParens);
+                    emitParenthesizedIf(templateSpan.expression, needsParens);
+
                     // Only emit if the literal is non-empty.
                     // The binary '+' operator is left-associative, so the first string concatenation
                     // with the head will force the result up to this point to be a string.
@@ -2394,8 +2510,6 @@ module ts {
                         return false;
                     case SyntaxKind.LabeledStatement:
                         return (<LabeledStatement>node.parent).label === node;
-                    case SyntaxKind.CatchClause:
-                        return (<CatchClause>node.parent).name === node;
                 }
             }
 
@@ -2409,7 +2523,20 @@ module ts {
                 }
             }
 
+            function getBlockScopedVariableId(node: Identifier): number {
+                // return undefined for synthesized nodes
+                return !nodeIsSynthesized(node) && resolver.getBlockScopedVariableId(node);
+            }
+
             function emitIdentifier(node: Identifier) {
+                var variableId = getBlockScopedVariableId(node);
+                if (variableId !== undefined && generatedBlockScopeNames) {
+                    var text = generatedBlockScopeNames[variableId];
+                    if (text) {
+                        write(text);
+                        return;
+                    }
+                }
                 if (!node.parent) {
                     write(node.text);
                 }
@@ -2479,7 +2606,7 @@ module ts {
                 emit((<SpreadElementExpression>node).expression);
             }
 
-            function needsParenthesisForPropertyAccess(node: Expression) {
+            function needsParenthesisForPropertyAccessOrInvocation(node: Expression) {
                 switch (node.kind) {
                     case SyntaxKind.Identifier:
                     case SyntaxKind.ArrayLiteralExpression:
@@ -2509,7 +2636,7 @@ module ts {
                     var e = elements[pos];
                     if (e.kind === SyntaxKind.SpreadElementExpression) {
                         e = (<SpreadElementExpression>e).expression;
-                        emitParenthesized(e, /*parenthesized*/ group === 0 && needsParenthesisForPropertyAccess(e));
+                        emitParenthesizedIf(e, /*parenthesized*/ group === 0 && needsParenthesisForPropertyAccessOrInvocation(e));
                         pos++;
                     }
                     else {
@@ -2555,14 +2682,6 @@ module ts {
                 }
             }
 
-            function createSynthesizedNode(kind: SyntaxKind): Node {
-                var node = createNode(kind);
-                node.pos = -1;
-                node.end = -1;
-
-                return node;
-            }
-
             function emitDownlevelObjectLiteralWithComputedProperties(node: ObjectLiteralExpression, firstComputedPropertyIndex: number): void {
                 var parenthesizedObjectLiteral = createDownlevelObjectLiteralWithComputedProperties(node, firstComputedPropertyIndex);
                 return emit(parenthesizedObjectLiteral);
@@ -2596,7 +2715,7 @@ module ts {
                 });
 
                 // Finally, return the temp variable.
-                propertyPatches = createBinaryExpression(propertyPatches, SyntaxKind.CommaToken, tempVar);
+                propertyPatches = createBinaryExpression(propertyPatches, SyntaxKind.CommaToken, createIdentifier(tempVar.text, /*startsOnNewLine:*/ true));
 
                 var result = createParenthesizedExpression(propertyPatches);
                 
@@ -2619,7 +2738,7 @@ module ts {
                 var leftHandSide = createMemberAccessForPropertyName(tempVar, property.name);
                 var maybeRightHandSide = tryGetRightHandSideOfPatchingPropertyAssignment(objectLiteral, property);
 
-                return maybeRightHandSide && createBinaryExpression(leftHandSide, SyntaxKind.EqualsToken, maybeRightHandSide);
+                return maybeRightHandSide && createBinaryExpression(leftHandSide, SyntaxKind.EqualsToken, maybeRightHandSide, /*startsOnNewLine:*/ true);
             }
 
             function tryGetRightHandSideOfPatchingPropertyAssignment(objectLiteral: ObjectLiteralExpression, property: ObjectLiteralElement) {
@@ -2692,8 +2811,8 @@ module ts {
                 return result;
             }
 
-            function createBinaryExpression(left: Expression, operator: SyntaxKind, right: Expression): BinaryExpression {
-                var result = <BinaryExpression>createSynthesizedNode(SyntaxKind.BinaryExpression);
+            function createBinaryExpression(left: Expression, operator: SyntaxKind, right: Expression, startsOnNewLine?: boolean): BinaryExpression {
+                var result = <BinaryExpression>createSynthesizedNode(SyntaxKind.BinaryExpression, startsOnNewLine);
                 result.operatorToken = createSynthesizedNode(operator);
                 result.left = left;
                 result.right = right;
@@ -2748,8 +2867,8 @@ module ts {
                 return result;
             }
             
-            function createIdentifier(name: string) {
-                var result = <Identifier>createSynthesizedNode(SyntaxKind.Identifier);
+            function createIdentifier(name: string, startsOnNewLine?: boolean) {
+                var result = <Identifier>createSynthesizedNode(SyntaxKind.Identifier, startsOnNewLine);
                 result.text = name;
 
                 return result;
@@ -2985,9 +3104,14 @@ module ts {
             }
 
             function emitTaggedTemplateExpression(node: TaggedTemplateExpression): void {
-                emit(node.tag);
-                write(" ");
-                emit(node.template);
+                if (compilerOptions.target >= ScriptTarget.ES6) {
+                    emit(node.tag);
+                    write(" ");
+                    emit(node.template);
+                }
+                else {
+                    emitDownlevelTaggedTemplate(node);
+                }
             }
 
             function emitParenExpression(node: ParenthesizedExpression) {
@@ -3088,9 +3212,11 @@ module ts {
 
                     write(tokenToString(node.operatorToken.kind));
 
+                    var shouldPlaceOnNewLine = !nodeIsSynthesized(node) && !nodeEndIsOnSameLineAsNodeStart(node.operatorToken, node.right);
+
                     // Check if the right expression is on a different line versus the operator itself.  If so,
                     // we'll emit newline.
-                    if (!nodeEndIsOnSameLineAsNodeStart(node.operatorToken, node.right)) {
+                    if (shouldPlaceOnNewLine || synthesizedNodeStartsOnNewLine(node.right)) {
                         increaseIndent();
                         writeLine();
                         emit(node.right);
@@ -3103,6 +3229,10 @@ module ts {
                 }
             }
 
+            function synthesizedNodeStartsOnNewLine(node: Node) {
+                return nodeIsSynthesized(node) && (<SynthesizedNode>node).startsOnNewLine;
+            }
+
             function emitConditionalExpression(node: ConditionalExpression) {
                 emit(node.condition);
                 write(" ? ");
@@ -3157,7 +3287,7 @@ module ts {
             }
 
             function emitExpressionStatement(node: ExpressionStatement) {
-                emitParenthesized(node.expression, /*parenthesized*/ node.expression.kind === SyntaxKind.ArrowFunction);
+                emitParenthesizedIf(node.expression, /*parenthesized*/ node.expression.kind === SyntaxKind.ArrowFunction);
                 write(";");
             }
 
@@ -3202,6 +3332,32 @@ module ts {
                 emitEmbeddedStatement(node.statement);
             }
 
+            function emitStartOfVariableDeclarationList(decl: Node, startPos?: number): void {
+                var tokenKind = SyntaxKind.VarKeyword;
+                if (decl && languageVersion >= ScriptTarget.ES6) {
+                    if (isLet(decl)) {
+                        tokenKind = SyntaxKind.LetKeyword;
+                    }
+                    else if (isConst(decl)) {
+                        tokenKind = SyntaxKind.ConstKeyword;
+                    }
+                }
+
+                if (startPos !== undefined) {
+                    emitToken(tokenKind, startPos);
+                }
+                else {
+                    switch (tokenKind) {
+                        case SyntaxKind.VarKeyword:
+                            return write("var ");
+                        case SyntaxKind.LetKeyword:
+                            return write("let ");
+                        case SyntaxKind.ConstKeyword:
+                            return write("const ");
+                    }
+                }
+            }
+
             function emitForStatement(node: ForStatement) {
                 var endPos = emitToken(SyntaxKind.ForKeyword, node.pos);
                 write(" ");
@@ -3209,17 +3365,9 @@ module ts {
                 if (node.initializer && node.initializer.kind === SyntaxKind.VariableDeclarationList) {
                     var variableDeclarationList = <VariableDeclarationList>node.initializer;
                     var declarations = variableDeclarationList.declarations;
-                    if (declarations[0] && isLet(declarations[0])) {
-                        emitToken(SyntaxKind.LetKeyword, endPos);
-                    }
-                    else if (declarations[0] && isConst(declarations[0])) {
-                        emitToken(SyntaxKind.ConstKeyword, endPos);
-                    }
-                    else {
-                        emitToken(SyntaxKind.VarKeyword, endPos);
-                    }
+                    emitStartOfVariableDeclarationList(declarations[0], endPos);
                     write(" ");
-                    emitCommaList(variableDeclarationList.declarations);
+                    emitCommaList(declarations);
                 }
                 else if (node.initializer) {
                     emit(node.initializer);
@@ -3240,12 +3388,7 @@ module ts {
                     var variableDeclarationList = <VariableDeclarationList>node.initializer;
                     if (variableDeclarationList.declarations.length >= 1) {
                         var decl = variableDeclarationList.declarations[0];
-                        if (isLet(decl)) {
-                            emitToken(SyntaxKind.LetKeyword, endPos);
-                        }
-                        else {
-                            emitToken(SyntaxKind.VarKeyword, endPos);
-                        }
+                        emitStartOfVariableDeclarationList(decl, endPos);
                         write(" ");
                         emit(decl);
                     }
@@ -3356,8 +3499,8 @@ module ts {
                 var endPos = emitToken(SyntaxKind.CatchKeyword, node.pos);
                 write(" ");
                 emitToken(SyntaxKind.OpenParenToken, endPos);
-                emit(node.name);
-                emitToken(SyntaxKind.CloseParenToken, node.name.end);
+                emit(node.variableDeclaration);
+                emitToken(SyntaxKind.CloseParenToken, node.variableDeclaration ? node.variableDeclaration.end : endPos);
                 write(" ");
                 emitBlock(node.block);
             }
@@ -3394,6 +3537,14 @@ module ts {
                 emitNode(node.name);
                 emitEnd(node.name);
             }
+            
+            function createVoidZero(): Expression {
+                var zero = <LiteralExpression>createSynthesizedNode(SyntaxKind.NumericLiteral);
+                zero.text = "0";
+                var result = <VoidExpression>createSynthesizedNode(SyntaxKind.VoidExpression);
+                result.expression = zero;
+                return result;
+            }
 
             function emitExportMemberAssignments(name: Identifier) {
                 if (exportSpecifiers && hasProperty(exportSpecifiers, name.text)) {
@@ -3427,6 +3578,8 @@ module ts {
                     if (emitCount++) {
                         write(", ");
                     }
+
+                    renameNonTopLevelLetAndConst(name);
                     if (name.parent && (name.parent.kind === SyntaxKind.VariableDeclaration || name.parent.kind === SyntaxKind.BindingElement)) {
                         emitModuleMemberName(<Declaration>name.parent);
                     }
@@ -3449,24 +3602,16 @@ module ts {
                     return expr;
                 }
 
-                function createVoidZero(): Expression {
-                    var zero = <LiteralExpression>createNode(SyntaxKind.NumericLiteral);
-                    zero.text = "0";
-                    var result = <VoidExpression>createNode(SyntaxKind.VoidExpression);
-                    result.expression = zero;
-                    return result;
-                }
-
                 function createDefaultValueCheck(value: Expression, defaultValue: Expression): Expression {
                     // The value expression will be evaluated twice, so for anything but a simple identifier
                     // we need to generate a temporary variable
                     value = ensureIdentifier(value);
                     // Return the expression 'value === void 0 ? defaultValue : value'
-                    var equals = <BinaryExpression>createNode(SyntaxKind.BinaryExpression);
+                    var equals = <BinaryExpression>createSynthesizedNode(SyntaxKind.BinaryExpression);
                     equals.left = value;
-                    equals.operatorToken = createNode(SyntaxKind.EqualsEqualsEqualsToken);
+                    equals.operatorToken = createSynthesizedNode(SyntaxKind.EqualsEqualsEqualsToken);
                     equals.right = createVoidZero();
-                    var cond = <ConditionalExpression>createNode(SyntaxKind.ConditionalExpression);
+                    var cond = <ConditionalExpression>createSynthesizedNode(SyntaxKind.ConditionalExpression);
                     cond.condition = equals;
                     cond.whenTrue = defaultValue;
                     cond.whenFalse = value;
@@ -3474,7 +3619,7 @@ module ts {
                 }
 
                 function createNumericLiteral(value: number) {
-                    var node = <LiteralExpression>createNode(SyntaxKind.NumericLiteral);
+                    var node = <LiteralExpression>createSynthesizedNode(SyntaxKind.NumericLiteral);
                     node.text = "" + value;
                     return node;
                 }
@@ -3483,7 +3628,7 @@ module ts {
                     if (expr.kind === SyntaxKind.Identifier || expr.kind === SyntaxKind.PropertyAccessExpression || expr.kind === SyntaxKind.ElementAccessExpression) {
                         return <LeftHandSideExpression>expr;
                     }
-                    var node = <ParenthesizedExpression>createNode(SyntaxKind.ParenthesizedExpression);
+                    var node = <ParenthesizedExpression>createSynthesizedNode(SyntaxKind.ParenthesizedExpression);
                     node.expression = expr;
                     return node;
                 }
@@ -3492,14 +3637,14 @@ module ts {
                     if (propName.kind !== SyntaxKind.Identifier) {
                         return createElementAccess(object, propName);
                     }
-                    var node = <PropertyAccessExpression>createNode(SyntaxKind.PropertyAccessExpression);
+                    var node = <PropertyAccessExpression>createSynthesizedNode(SyntaxKind.PropertyAccessExpression);
                     node.expression = parenthesizeForAccess(object);
                     node.name = propName;
                     return node;
                 }
 
                 function createElementAccess(object: Expression, index: Expression): Expression {
-                    var node = <ElementAccessExpression>createNode(SyntaxKind.ElementAccessExpression);
+                    var node = <ElementAccessExpression>createSynthesizedNode(SyntaxKind.ElementAccessExpression);
                     node.expression = parenthesizeForAccess(object);
                     node.argumentExpression = index;
                     return node;
@@ -3638,8 +3783,31 @@ module ts {
                     }
                 }
                 else {
+                    var isLet = renameNonTopLevelLetAndConst(<Identifier>node.name);
                     emitModuleMemberName(node);
-                    emitOptional(" = ", node.initializer);
+
+                    var initializer = node.initializer;
+                    if (!initializer && languageVersion < ScriptTarget.ES6) {
+
+                        // downlevel emit for non-initialized let bindings defined in loops
+                        // for (...) {  let x; }
+                        // should be
+                        // for (...) { var <some-uniqie-name> = void 0; }
+                        // this is necessary to preserve ES6 semantic in scenarios like
+                        // for (...) { let x; console.log(x); x = 1 } // assignment on one iteration should not affect other iterations
+                        var isUninitializedLet =
+                            (resolver.getNodeCheckFlags(node) & NodeCheckFlags.BlockScopedBindingInLoop) &&
+                            (getCombinedFlagsForIdentifier(<Identifier>node.name) & NodeFlags.Let);
+
+                        // NOTE: default initialization should not be added to let bindings in for-in\for-of statements
+                        if (isUninitializedLet &&
+                            node.parent.parent.kind !== SyntaxKind.ForInStatement &&
+                            node.parent.parent.kind !== SyntaxKind.ForOfStatement) {
+                            initializer = createVoidZero();
+                        }
+                    }
+
+                    emitOptional(" = ", initializer);
                 }
             }
 
@@ -3652,18 +3820,86 @@ module ts {
                     forEach((<BindingPattern>name).elements, emitExportVariableAssignments);
                 }
             }
+            
+            function getEnclosingBlockScopeContainer(node: Node): Node {
+                var current = node;
+                while (current) {
+                    if (isAnyFunction(current)) {
+                        return current;
+                    }
+                    switch (current.kind) {
+                        case SyntaxKind.SourceFile:
+                        case SyntaxKind.SwitchKeyword:
+                        case SyntaxKind.CatchClause:
+                        case SyntaxKind.ModuleDeclaration:
+                        case SyntaxKind.ForStatement:
+                        case SyntaxKind.ForInStatement:
+                        case SyntaxKind.ForOfStatement:
+                            return current;
+                        case SyntaxKind.Block:
+                            // function block is not considered block-scope container
+                            // see comment in binder.ts: bind(...), case for SyntaxKind.Block
+                            if (!isAnyFunction(current.parent)) {
+                                return current;
+                            }
+                    }
+
+                    current = current.parent;
+                }
+            }
+            
+
+            function getCombinedFlagsForIdentifier(node: Identifier): NodeFlags {
+                if (!node.parent || (node.parent.kind !== SyntaxKind.VariableDeclaration && node.parent.kind !== SyntaxKind.BindingElement)) {
+                    return 0;
+                }
+
+                return getCombinedNodeFlags(node.parent);
+            }
+
+            function renameNonTopLevelLetAndConst(node: Node): void {
+                // do not rename if
+                // - language version is ES6+
+                // - node is synthesized
+                // - node is not identifier (can happen when tree is malformed)
+                // - node is definitely not name of variable declaration. 
+                // it still can be part of parameter declaration, this check will be done next
+                if (languageVersion >= ScriptTarget.ES6 ||
+                    nodeIsSynthesized(node) ||
+                    node.kind !== SyntaxKind.Identifier ||
+                    (node.parent.kind !== SyntaxKind.VariableDeclaration && node.parent.kind !== SyntaxKind.BindingElement)) {
+                    return;
+                }
+
+                var combinedFlags = getCombinedFlagsForIdentifier(<Identifier>node);
+                if (((combinedFlags & NodeFlags.BlockScoped) === 0) || combinedFlags & NodeFlags.Export) {
+                    // do not rename exported or non-block scoped variables
+                    return;
+                }
+
+                // here it is known that node is a block scoped variable
+                var list = getAncestor(node, SyntaxKind.VariableDeclarationList);
+                if (list.parent.kind === SyntaxKind.VariableStatement && list.parent.parent.kind === SyntaxKind.SourceFile) {
+                    // do not rename variables that are defined on source file level
+                    return;
+                }
+
+                var blockScopeContainer = getEnclosingBlockScopeContainer(node);
+                var parent = blockScopeContainer.kind === SyntaxKind.SourceFile
+                    ? blockScopeContainer
+                    : blockScopeContainer.parent;
+
+                var generatedName = generateUniqueNameForLocation(parent, (<Identifier>node).text);
+                var variableId = resolver.getBlockScopedVariableId(<Identifier>node);
+                if (!generatedBlockScopeNames) {
+                    generatedBlockScopeNames = [];
+                }
+                generatedBlockScopeNames[variableId] = generatedName;
+            }
 
             function emitVariableStatement(node: VariableStatement) {
                 if (!(node.flags & NodeFlags.Export)) {
-                    if (isLet(node.declarationList)) {
-                        write("let ");
-                    }
-                    else if (isConst(node.declarationList)) {
-                        write("const ");
-                    }
-                    else {
-                        write("var ");
-                    }
+                    emitStartOfVariableDeclarationList(node.declarationList);
                 }
                 emitCommaList(node.declarationList.declarations);
                 write(";");
@@ -3840,6 +4076,8 @@ module ts {
                 tempVariables = undefined;
                 tempParameters = undefined;
 
+                var popFrame = enterNameScope()
+
                 // When targeting ES6, emit arrow function natively in ES6
                 if (shouldEmitAsArrowFunction(node)) {
                     emitSignatureParametersForArrow(node);
@@ -3871,6 +4109,8 @@ module ts {
                     write(";");
                 }
 
+                exitNameScope(popFrame);
+
                 tempCount = saveTempCount;
                 tempVariables = saveTempVariables;
                 tempParameters = saveTempParameters;
@@ -4192,6 +4432,9 @@ module ts {
                     tempCount = 0;
                     tempVariables = undefined;
                     tempParameters = undefined;
+
+                    var popFrame = enterNameScope();
+
                     // Emit the constructor overload pinned comments
                     forEach(node.members, member => {
                         if (member.kind === SyntaxKind.Constructor && !(<ConstructorDeclaration>member).body) {
@@ -4252,6 +4495,9 @@ module ts {
                     if (ctor) {
                         emitTrailingComments(ctor);
                     }
+
+                    exitNameScope(popFrame);
+
                     tempCount = saveTempCount;
                     tempVariables = saveTempVariables;
                     tempParameters = saveTempParameters;
@@ -4384,7 +4630,11 @@ module ts {
                     var saveTempVariables = tempVariables;
                     tempCount = 0;
                     tempVariables = undefined;
+                    var popFrame = enterNameScope();
+
                     emit(node.body);
+
+                    exitNameScope(popFrame);
                     tempCount = saveTempCount;
                     tempVariables = saveTempVariables;
                 }

src/compiler/parser.ts

@@ -222,8 +222,7 @@ module ts {
                     visitNode(cbNode, (<TryStatement>node).catchClause) ||
                     visitNode(cbNode, (<TryStatement>node).finallyBlock);
             case SyntaxKind.CatchClause:
-                return visitNode(cbNode, (<CatchClause>node).name) ||
-                    visitNode(cbNode, (<CatchClause>node).type) ||
+                return visitNode(cbNode, (<CatchClause>node).variableDeclaration) ||
                     visitNode(cbNode, (<CatchClause>node).block);
             case SyntaxKind.ClassDeclaration:
                 return visitNodes(cbNodes, node.modifiers) ||
@@ -3973,9 +3972,10 @@ module ts {
         function parseCatchClause(): CatchClause {
             var result = <CatchClause>createNode(SyntaxKind.CatchClause);
             parseExpected(SyntaxKind.CatchKeyword);
-            parseExpected(SyntaxKind.OpenParenToken);
-            result.name = parseIdentifier();
-            result.type = parseTypeAnnotation();
+            if (parseExpected(SyntaxKind.OpenParenToken)) {
+                result.variableDeclaration = parseVariableDeclaration();
+            }
+
             parseExpected(SyntaxKind.CloseParenToken);
             result.block = parseBlock(/*ignoreMissingOpenBrace:*/ false, /*checkForStrictMode:*/ false);
             return finishNode(result);

src/compiler/program.ts

@@ -3,6 +3,7 @@
 
 module ts {
     /* @internal */ export var emitTime = 0;
+    /* @internal */ export var ioReadTime = 0;
 
     export function createCompilerHost(options: CompilerOptions): CompilerHost {
         var currentDirectory: string;
@@ -19,7 +20,9 @@ module ts {
 
         function getSourceFile(fileName: string, languageVersion: ScriptTarget, onError?: (message: string) => void): SourceFile {
             try {
+                var start = new Date().getTime();
                 var text = sys.readFile(fileName, options.charset);
+                ioReadTime += new Date().getTime() - start;
             }
             catch (e) {
                 if (onError) {

src/compiler/tsc.ts

@@ -322,6 +322,7 @@ module ts {
     }
 
     function compile(fileNames: string[], compilerOptions: CompilerOptions, compilerHost: CompilerHost) {
+        ts.ioReadTime = 0;
         ts.parseTime = 0;
         ts.bindTime = 0;
         ts.checkTime = 0;
@@ -330,9 +331,12 @@ module ts {
         var start = new Date().getTime();
 
         var program = createProgram(fileNames, compilerOptions, compilerHost);
+        var programTime = new Date().getTime() - start;
+
         var exitStatus = compileProgram();
 
         var end = new Date().getTime() - start;
+        var compileTime = end - programTime;
 
         if (compilerOptions.listFiles) {
             forEach(program.getSourceFiles(), file => {
@@ -353,10 +357,19 @@ module ts {
                 reportStatisticalValue("Memory used", Math.round(memoryUsed / 1000) + "K");
             }
 
-            reportTimeStatistic("Parse time", ts.parseTime);
+            // Individual component times.
+            // Note: we output 'programTime' as parseTime to match the tsc 1.3 behavior.  tsc 1.3
+            // measured parse time along with read IO as a single counter.  We preserve that 
+            // behavior so we can accurately compare times.  For actual parse times (in isolation)
+            // is reported below.
+            reportTimeStatistic("Parse time", programTime);
             reportTimeStatistic("Bind time", ts.bindTime);
             reportTimeStatistic("Check time", ts.checkTime);
             reportTimeStatistic("Emit time", ts.emitTime);
+            
+            reportTimeStatistic("Parse time w/o IO", ts.parseTime);
+            reportTimeStatistic("IO read", ts.ioReadTime);
+            reportTimeStatistic("Compile time", compileTime);
             reportTimeStatistic("Total time", end);
         }
 

src/compiler/types.ts

@@ -121,7 +121,6 @@ module ts {
         WithKeyword,
         // Strict mode reserved words
         AsKeyword,
-        FromKeyword,
         ImplementsKeyword,
         InterfaceKeyword,
         LetKeyword,
@@ -131,7 +130,7 @@ module ts {
         PublicKeyword,
         StaticKeyword,
         YieldKeyword,
-        // TypeScript keywords
+        // Contextual keywords
         AnyKeyword,
         BooleanKeyword,
         ConstructorKeyword,
@@ -144,7 +143,9 @@ module ts {
         StringKeyword,
         SymbolKeyword,
         TypeKeyword,
+        FromKeyword,
         OfKeyword, // LastKeyword and LastToken
+
         // Parse tree nodes
 
         // Names
@@ -279,7 +280,7 @@ module ts {
         FirstPunctuation = OpenBraceToken,
         LastPunctuation = CaretEqualsToken,
         FirstToken = Unknown,
-        LastToken = OfKeyword,
+        LastToken = LastKeyword,
         FirstTriviaToken = SingleLineCommentTrivia,
         LastTriviaToken = ConflictMarkerTrivia,
         FirstLiteralToken = NumericLiteral,
@@ -813,9 +814,8 @@ module ts {
         finallyBlock?: Block;
     }
 
-    export interface CatchClause extends Declaration {
-        name: Identifier;
-        type?: TypeNode;
+    export interface CatchClause extends Node {
+        variableDeclaration: VariableDeclaration;
         block: Block;
     }
 
@@ -1204,6 +1204,7 @@ module ts {
         // Returns the constant value this property access resolves to, or 'undefined' for a non-constant
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         isUnknownIdentifier(location: Node, name: string): boolean;
+        getBlockScopedVariableId(node: Identifier): number;
     }
 
     export const enum SymbolFlags {
@@ -1329,6 +1330,7 @@ module ts {
 
         // Values for enum members have been computed, and any errors have been reported for them.
         EnumValuesComputed  = 0x00000080,
+        BlockScopedBindingInLoop = 0x00000100,
     }
 
     export interface NodeLinks {

src/compiler/utilities.ts

@@ -7,6 +7,12 @@ module ts {
         isNoDefaultLib?: boolean
     }
 
+    export interface SynthesizedNode extends Node {
+        leadingCommentRanges?: CommentRange[];
+        trailingCommentRanges?: CommentRange[];
+        startsOnNewLine: boolean;
+    }
+
     export function getDeclarationOfKind(symbol: Symbol, kind: SyntaxKind): Declaration {
         var declarations = symbol.declarations;
         for (var i = 0; i < declarations.length; i++) {
@@ -192,6 +198,18 @@ module ts {
         return getBaseFileName(moduleName).replace(/\W/g, "_");
     }
 
+    export function isBlockOrCatchScoped(declaration: Declaration) {
+        return (getCombinedNodeFlags(declaration) & NodeFlags.BlockScoped) !== 0 ||
+            isCatchClauseVariableDeclaration(declaration);
+    }
+
+    export function isCatchClauseVariableDeclaration(declaration: Declaration) {
+        return declaration &&
+            declaration.kind === SyntaxKind.VariableDeclaration &&
+            declaration.parent &&
+            declaration.parent.kind === SyntaxKind.CatchClause;
+    }
+
     // Return display name of an identifier
     // Computed property names will just be emitted as "[<expr>]", where <expr> is the source
     // text of the expression in the computed property.
@@ -665,7 +683,7 @@ module ts {
     }
 
     export function isBindingPattern(node: Node) {
-        return node.kind === SyntaxKind.ArrayBindingPattern || node.kind === SyntaxKind.ObjectBindingPattern;
+        return !!node && (node.kind === SyntaxKind.ArrayBindingPattern || node.kind === SyntaxKind.ObjectBindingPattern);
     }
 
     export function isInAmbientContext(node: Node): boolean {
@@ -681,31 +699,33 @@ module ts {
 
     export function isDeclaration(node: Node): boolean {
         switch (node.kind) {
-            case SyntaxKind.TypeParameter:
-            case SyntaxKind.Parameter:
-            case SyntaxKind.VariableDeclaration:
+            case SyntaxKind.ArrowFunction:
             case SyntaxKind.BindingElement:
-            case SyntaxKind.PropertyDeclaration:
-            case SyntaxKind.PropertySignature:
-            case SyntaxKind.PropertyAssignment:
-            case SyntaxKind.ShorthandPropertyAssignment:
+            case SyntaxKind.ClassDeclaration:
+            case SyntaxKind.Constructor:
+            case SyntaxKind.EnumDeclaration:
             case SyntaxKind.EnumMember:
+            case SyntaxKind.ExportSpecifier:
+            case SyntaxKind.FunctionDeclaration:
+            case SyntaxKind.FunctionExpression:
+            case SyntaxKind.GetAccessor:
+            case SyntaxKind.ImportClause:
+            case SyntaxKind.ImportEqualsDeclaration:
+            case SyntaxKind.ImportSpecifier:
+            case SyntaxKind.InterfaceDeclaration:
             case SyntaxKind.MethodDeclaration:
             case SyntaxKind.MethodSignature:
-            case SyntaxKind.FunctionDeclaration:
-            case SyntaxKind.GetAccessor:
-            case SyntaxKind.SetAccessor:
-            case SyntaxKind.Constructor:
-            case SyntaxKind.ClassDeclaration:
-            case SyntaxKind.InterfaceDeclaration:
-            case SyntaxKind.TypeAliasDeclaration:
-            case SyntaxKind.EnumDeclaration:
             case SyntaxKind.ModuleDeclaration:
-            case SyntaxKind.ImportEqualsDeclaration:
-            case SyntaxKind.ImportClause:
-            case SyntaxKind.ImportSpecifier:
             case SyntaxKind.NamespaceImport:
-            case SyntaxKind.ExportSpecifier:
+            case SyntaxKind.Parameter:
+            case SyntaxKind.PropertyAssignment:
+            case SyntaxKind.PropertyDeclaration:
+            case SyntaxKind.PropertySignature:
+            case SyntaxKind.SetAccessor:
+            case SyntaxKind.ShorthandPropertyAssignment:
+            case SyntaxKind.TypeAliasDeclaration:
+            case SyntaxKind.TypeParameter:
+            case SyntaxKind.VariableDeclaration:
                 return true;
         }
         return false;
@@ -739,7 +759,7 @@ module ts {
     }
 
     // True if the given identifier, string literal, or number literal is the name of a declaration node
-    export function isDeclarationOrFunctionExpressionOrCatchVariableName(name: Node): boolean {
+    export function isDeclarationName(name: Node): boolean {
         if (name.kind !== SyntaxKind.Identifier && name.kind !== SyntaxKind.StringLiteral && name.kind !== SyntaxKind.NumericLiteral) {
             return false;
         }
@@ -751,14 +771,10 @@ module ts {
             }
         }
 
-        if (isDeclaration(parent) || parent.kind === SyntaxKind.FunctionExpression) {
+        if (isDeclaration(parent)) {
             return (<Declaration>parent).name === name;
         }
 
-        if (parent.kind === SyntaxKind.CatchClause) {
-            return (<CatchClause>parent).name === name;
-        }
-
         return false;
     }
 
@@ -1123,7 +1139,44 @@ module ts {
         return createTextChangeRange(createTextSpanFromBounds(oldStartN, oldEndN), /*newLength: */newEndN - oldStartN);
     }
 
-    // @internal
+    export function nodeStartsNewLexicalEnvironment(n: Node): boolean {
+        return isAnyFunction(n) || n.kind === SyntaxKind.ModuleDeclaration || n.kind === SyntaxKind.SourceFile;
+    }
+
+    export function nodeIsSynthesized(node: Node): boolean {
+        return node.pos === -1 && node.end === -1;
+    }
+
+    export function createSynthesizedNode(kind: SyntaxKind, startsOnNewLine?: boolean): Node {
+        var node = <SynthesizedNode>createNode(kind);
+        node.pos = -1;
+        node.end = -1;
+        node.startsOnNewLine = startsOnNewLine;
+        return node;
+    }
+
+    export function generateUniqueName(baseName: string, isExistingName: (name: string) => boolean): string {
+        // First try '_name'
+        if (baseName.charCodeAt(0) !== CharacterCodes._) {
+            var baseName = "_" + baseName;
+            if (!isExistingName(baseName)) {
+                return baseName;
+            }
+        }
+        // Find the first unique '_name_n', where n is a positive number
+        if (baseName.charCodeAt(baseName.length - 1) !== CharacterCodes._) {
+            baseName += "_";
+        }
+        var i = 1;
+        while (true) {
+            var name = baseName + i;
+            if (!isExistingName(name)) {
+                return name;
+            }
+            i++;
+        }
+    }
+
     export function createDiagnosticCollection(): DiagnosticCollection {
         var nonFileDiagnostics: Diagnostic[] = [];
         var fileDiagnostics: Map<Diagnostic[]> = {};

src/harness/harnessLanguageService.ts

@@ -1,4 +1,4 @@
-/// <reference path='..\services\services.ts' />
+/// <reference path='..\services\services.ts' />
 /// <reference path='..\services\shims.ts' />
 /// <reference path='..\server\client.ts' />
 /// <reference path='harness.ts' />

src/services/services.ts

@@ -58,9 +58,10 @@ module ts {
     }
 
     export interface SourceFile {
-        version: string;
-        scriptSnapshot: IScriptSnapshot;
-        nameTable: Map<string>;
+        /* @internal */ version: string;
+        /* @internal */ scriptSnapshot: IScriptSnapshot;
+        /* @internal */ nameTable: Map<string>;
+
         getNamedDeclarations(): Declaration[];
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
         getLineStarts(): number[];
@@ -1270,31 +1271,21 @@ module ts {
 
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the 
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file 
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file. 
+          * @param version Current version of the file.
           */
         updateDocument(
-            sourceFile: SourceFile,
             fileName: string,
             compilationSettings: CompilerOptions,
             scriptSnapshot: IScriptSnapshot,
-            version: string,
-            textChangeRange: TextChangeRange): SourceFile;
+            version: string): SourceFile;
 
         /**
           * Informs the DocumentRegistry that a file is not needed any longer.
@@ -1442,7 +1433,11 @@ module ts {
 
     interface DocumentRegistryEntry {
         sourceFile: SourceFile;
-        refCount: number;
+
+        // The number of language services that this source file is referenced in.   When no more
+        // language services are referencing the file, then the file can be removed from the 
+        // registry.
+        languageServiceRefCount: number;
         owners: string[];
     }
 
@@ -1671,6 +1666,8 @@ module ts {
     }
 
     export function createDocumentRegistry(): DocumentRegistry {
+        // Maps from compiler setting target (ES3, ES5, etc.) to all the cached documents we have
+        // for those settings.
         var buckets: Map<Map<DocumentRegistryEntry>> = {};
 
         function getKeyFromCompilationSettings(settings: CompilerOptions): string {
@@ -1694,7 +1691,7 @@ module ts {
                     var entry = entries[i];
                     sourceFiles.push({
                         name: i,
-                        refCount: entry.refCount,
+                        refCount: entry.languageServiceRefCount,
                         references: entry.owners.slice(0)
                     });
                 }
@@ -1707,43 +1704,54 @@ module ts {
             return JSON.stringify(bucketInfoArray, null, 2);
         }
 
-        function acquireDocument(
-            fileName: string,
-            compilationSettings: CompilerOptions,
-            scriptSnapshot: IScriptSnapshot,
-            version: string): SourceFile {
-
-            var bucket = getBucketForCompilationSettings(compilationSettings, /*createIfMissing*/ true);
-            var entry = lookUp(bucket, fileName);
-            if (!entry) {
-                var sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, compilationSettings.target, version, /*setNodeParents:*/ false);
-
-                bucket[fileName] = entry = {
-                    sourceFile: sourceFile,
-                    refCount: 0,
-                    owners: []
-                };
-            }
-            entry.refCount++;
-
-            return entry.sourceFile;
+        function acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile {
+            return acquireOrUpdateDocument(fileName, compilationSettings, scriptSnapshot, version, /*acquiring:*/ true);
         }
 
-        function updateDocument(
-            sourceFile: SourceFile,
+        function updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile {
+            return acquireOrUpdateDocument(fileName, compilationSettings, scriptSnapshot, version, /*acquiring:*/ false);
+        }
+
+        function acquireOrUpdateDocument(
             fileName: string,
             compilationSettings: CompilerOptions,
             scriptSnapshot: IScriptSnapshot,
             version: string,
-            textChangeRange: TextChangeRange
-            ): SourceFile {
+            acquiring: boolean): SourceFile {
 
-            var bucket = getBucketForCompilationSettings(compilationSettings, /*createIfMissing*/ false);
-            Debug.assert(bucket !== undefined);
+            var bucket = getBucketForCompilationSettings(compilationSettings, /*createIfMissing*/ true);
             var entry = lookUp(bucket, fileName);
-            Debug.assert(entry !== undefined);
+            if (!entry) {
+                Debug.assert(acquiring, "How could we be trying to update a document that the registry doesn't have?");
+
+                // Have never seen this file with these settings.  Create a new source file for it.
+                var sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, compilationSettings.target, version, /*setNodeParents:*/ false);
+
+                bucket[fileName] = entry = {
+                    sourceFile: sourceFile,
+                    languageServiceRefCount: 0,
+                    owners: []
+                };
+            }
+            else {
+                // We have an entry for this file.  However, it may be for a different version of 
+                // the script snapshot.  If so, update it appropriately.  Otherwise, we can just
+                // return it as is.
+                if (entry.sourceFile.version !== version) {
+                    entry.sourceFile = updateLanguageServiceSourceFile(entry.sourceFile, scriptSnapshot, version,
+                        scriptSnapshot.getChangeRange(entry.sourceFile.scriptSnapshot));
+                }
+            }
+
+            // If we're acquiring, then this is the first time this LS is asking for this document.
+            // Increase our ref count so we know there's another LS using the document.  If we're
+            // not acquiring, then that means the LS is 'updating' the file instead, and that means
+            // it has already acquired the document previously.  As such, we do not need to increase
+            // the ref count.
+            if (acquiring) {
+                entry.languageServiceRefCount++;
+            }
 
-            entry.sourceFile = updateLanguageServiceSourceFile(entry.sourceFile, scriptSnapshot, version, textChangeRange);
             return entry.sourceFile;
         }
 
@@ -1752,10 +1760,10 @@ module ts {
             Debug.assert(bucket !== undefined);
 
             var entry = lookUp(bucket, fileName);
-            entry.refCount--;
+            entry.languageServiceRefCount--;
 
-            Debug.assert(entry.refCount >= 0);
-            if (entry.refCount === 0) {
+            Debug.assert(entry.languageServiceRefCount >= 0);
+            if (entry.languageServiceRefCount === 0) {
                 delete bucket[fileName];
             }
         }
@@ -1788,33 +1796,140 @@ module ts {
             });
         }
 
+        function recordModuleName() {
+            var importPath = scanner.getTokenValue();
+            var pos = scanner.getTokenPos();
+            importedFiles.push({
+                fileName: importPath,
+                pos: pos,
+                end: pos + importPath.length
+            });
+        }
+
         function processImport(): void {
             scanner.setText(sourceText);
             var token = scanner.scan();
             // Look for:
-            // import foo = module("foo");
+            //    import "mod";
+            //    import d from "mod"
+            //    import {a as A } from "mod";
+            //    import * as NS  from "mod"
+            //    import d, {a, b as B} from "mod"
+            //    import i = require("mod");
+            //
+            //    export * from "mod"
+            //    export {a as b} from "mod"
+
             while (token !== SyntaxKind.EndOfFileToken) {
                 if (token === SyntaxKind.ImportKeyword) {
                     token = scanner.scan();
-                    if (token === SyntaxKind.Identifier) {
-                        token = scanner.scan();
-                        if (token === SyntaxKind.EqualsToken) {
+                    if (token === SyntaxKind.StringLiteral) {
+                        // import "mod";
+                        recordModuleName();
+                        continue;
+                    }
+                    else {
+                        if (token === SyntaxKind.Identifier) {
                             token = scanner.scan();
-                            if (token === SyntaxKind.RequireKeyword) {
+                            if (token === SyntaxKind.FromKeyword) {
                                 token = scanner.scan();
-                                if (token === SyntaxKind.OpenParenToken) {
+                                if (token === SyntaxKind.StringLiteral) {
+                                    // import d from "mod";
+                                    recordModuleName();
+                                    continue
+                                }
+                            }
+                            else if (token === SyntaxKind.EqualsToken) {
+                                token = scanner.scan();
+                                if (token === SyntaxKind.RequireKeyword) {
                                     token = scanner.scan();
-                                    if (token === SyntaxKind.StringLiteral) {
-                                        var importPath = scanner.getTokenValue();
-                                        var pos = scanner.getTokenPos();
-                                        importedFiles.push({
-                                            fileName: importPath,
-                                            pos: pos,
-                                            end: pos + importPath.length
-                                        });
+                                    if (token === SyntaxKind.OpenParenToken) {
+                                        token = scanner.scan();
+                                        if (token === SyntaxKind.StringLiteral) {
+                                            //  import i = require("mod");
+                                            recordModuleName();
+                                            continue;
+                                        }
                                     }
                                 }
                             }
+                            else if (token === SyntaxKind.CommaToken) {
+                                // consume comma and keep going
+                                token = scanner.scan();
+                            }
+                            else {
+                                // unknown syntax
+                                continue;
+                            }
+                        }
+
+                        if (token === SyntaxKind.OpenBraceToken) {
+                            token = scanner.scan();
+                            // consume "{ a as B, c, d as D}" clauses
+                            while (token !== SyntaxKind.CloseBraceToken) {
+                                token = scanner.scan();
+                            }
+
+                            if (token === SyntaxKind.CloseBraceToken) {
+                                token = scanner.scan();
+                                if (token === SyntaxKind.FromKeyword) {
+                                    token = scanner.scan();
+                                    if (token === SyntaxKind.StringLiteral) {
+                                        // import {a as A} from "mod";
+                                        // import d, {a, b as B} from "mod"
+                                        recordModuleName();
+                                    }
+                                }
+                            }
+                        }
+                        else if (token === SyntaxKind.AsteriskToken) {
+                            token = scanner.scan();
+                            if (token === SyntaxKind.AsKeyword) {
+                                token = scanner.scan();
+                                if (token === SyntaxKind.Identifier) {
+                                    token = scanner.scan();
+                                    if (token === SyntaxKind.FromKeyword) {
+                                        token = scanner.scan();
+                                        if (token === SyntaxKind.StringLiteral) {
+                                            // import * as NS from "mod"
+                                            // import d, * as NS from "mod"
+                                            recordModuleName();
+                                        }
+                                    }
+                                }
+                            }
+                        }
+                    }
+                }
+                else if (token === SyntaxKind.ExportKeyword) {
+                    token = scanner.scan();
+                    if (token === SyntaxKind.OpenBraceToken) {
+                        token = scanner.scan();
+                        // consume "{ a as B, c, d as D}" clauses
+                        while (token !== SyntaxKind.CloseBraceToken) {
+                            token = scanner.scan();
+                        }
+
+                        if (token === SyntaxKind.CloseBraceToken) {
+                            token = scanner.scan();
+                            if (token === SyntaxKind.FromKeyword) {
+                                token = scanner.scan();
+                                if (token === SyntaxKind.StringLiteral) {
+                                    // export {a as A} from "mod";
+                                    // export {a, b as B} from "mod"
+                                    recordModuleName();
+                                }
+                            }
+                        }
+                    }
+                    else if (token === SyntaxKind.AsteriskToken) {
+                        token = scanner.scan();
+                        if (token === SyntaxKind.FromKeyword) {
+                            token = scanner.scan();
+                            if (token === SyntaxKind.StringLiteral) {
+                                // export * from "mod"
+                                recordModuleName();
+                            }
                         }
                     }
                 }
@@ -2162,19 +2277,34 @@ module ts {
                 // it is safe to reuse the souceFiles; if not, then the shape of the AST can change, and the oldSourceFile
                 // can not be reused. we have to dump all syntax trees and create new ones.
                 if (!changesInCompilationSettingsAffectSyntax) {
-
                     // Check if the old program had this file already
                     var oldSourceFile = program && program.getSourceFile(fileName);
                     if (oldSourceFile) {
-                        // This SourceFile is safe to reuse, return it
-                        if (sourceFileUpToDate(oldSourceFile)) {
-                            return oldSourceFile;
-                        }
-
-                        // We have an older version of the sourceFile, incrementally parse the changes
-                        var textChangeRange = hostFileInformation.scriptSnapshot.getChangeRange(oldSourceFile.scriptSnapshot);
-                        return documentRegistry.updateDocument(oldSourceFile, fileName, newSettings, hostFileInformation.scriptSnapshot, hostFileInformation.version, textChangeRange);
+                        // We already had a source file for this file name.  Go to the registry to 
+                        // ensure that we get the right up to date version of it.  We need this to
+                        // address the following 'race'.  Specifically, say we have the following:
+                        //
+                        //      LS1
+                        //          \
+                        //           DocumentRegistry
+                        //          /
+                        //      LS2
+                        //
+                        // Each LS has a reference to file 'foo.ts' at version 1.  LS2 then updates
+                        // it's version of 'foo.ts' to version 2.  This will cause LS2 and the 
+                        // DocumentRegistry to have version 2 of the document.  HOwever, LS1 will 
+                        // have version 1.  And *importantly* this source file will be *corrupt*.
+                        // The act of creating version 2 of the file irrevocably damages the version
+                        // 1 file.
+                        //
+                        // So, later when we call into LS1, we need to make sure that it doesn't use
+                        // it's source file any more, and instead defers to DocumentRegistry to get
+                        // either version 1, version 2 (or some other version) depending on what the 
+                        // host says should be used.
+                        return documentRegistry.updateDocument(fileName, newSettings, hostFileInformation.scriptSnapshot, hostFileInformation.version);
                     }
+
+                    // We didn't already have the file.  Fall through and acquire it from the registry.
                 }
 
                 // Could not find this file in the old program, create a new SourceFile for it.
@@ -2228,8 +2358,8 @@ module ts {
 
         function dispose(): void {
             if (program) {
-                forEach(program.getSourceFiles(),
-                    (f) => { documentRegistry.releaseDocument(f.fileName, program.getCompilerOptions()); });
+                forEach(program.getSourceFiles(), f =>
+                    documentRegistry.releaseDocument(f.fileName, program.getCompilerOptions()));
             }
         }
 
@@ -4009,27 +4139,6 @@ module ts {
             return getReferencesForNode(node, program.getSourceFiles(), /*searchOnlyInCurrentFile*/ false, findInStrings, findInComments);
         }
 
-        function initializeNameTable(sourceFile: SourceFile): void {
-            var nameTable: Map<string> = {};
-
-            walk(sourceFile);
-            sourceFile.nameTable = nameTable;
-
-            function walk(node: Node) {
-                switch (node.kind) {
-                    case SyntaxKind.Identifier:
-                        nameTable[(<Identifier>node).text] = (<Identifier>node).text;
-                        break;
-                    case SyntaxKind.StringLiteral:
-                    case SyntaxKind.NumericLiteral:
-                        nameTable[(<LiteralExpression>node).text] = (<LiteralExpression>node).text;
-                        break;
-                    default:
-                        forEachChild(node, walk);
-                }
-            } 
-        }
-
         function getReferencesForNode(node: Node, sourceFiles: SourceFile[], searchOnlyInCurrentFile: boolean, findInStrings: boolean, findInComments: boolean): ReferenceEntry[] {
             // Labels
             if (isLabelName(node)) {
@@ -4096,13 +4205,9 @@ module ts {
                     forEach(sourceFiles, sourceFile => {
                         cancellationToken.throwIfCancellationRequested();
 
-                        if (!sourceFile.nameTable) {
-                            initializeNameTable(sourceFile)
-                        }
+                        var nameTable = getNameTable(sourceFile);
 
-                        Debug.assert(sourceFile.nameTable !== undefined);
-
-                        if (lookUp(sourceFile.nameTable, internedName)) {
+                        if (lookUp(nameTable, internedName)) {
                             result = result || [];
                             getReferencesInNode(sourceFile, symbol, declaredName, node, searchMeaning, findInStrings, findInComments, result);
                         }
@@ -4756,7 +4861,7 @@ module ts {
 
         /** A node is considered a writeAccess iff it is a name of a declaration or a target of an assignment */
         function isWriteAccess(node: Node): boolean {
-            if (node.kind === SyntaxKind.Identifier && isDeclarationOrFunctionExpressionOrCatchVariableName(node)) {
+            if (node.kind === SyntaxKind.Identifier && isDeclarationName(node)) {
                 return true;
             }
 
@@ -4918,7 +5023,7 @@ module ts {
             else if (isInRightSideOfImport(node)) {
                 return getMeaningFromRightHandSideOfImportEquals(node);
             }
-            else if (isDeclarationOrFunctionExpressionOrCatchVariableName(node)) {
+            else if (isDeclarationName(node)) {
                 return getMeaningFromDeclaration(node.parent);
             }
             else if (isTypeReference(node)) {
@@ -5646,6 +5751,52 @@ module ts {
         };
     }
 
+    /* @internal */
+    export function getNameTable(sourceFile: SourceFile): Map<string> {
+        if (!sourceFile.nameTable) {
+            initializeNameTable(sourceFile)
+        }
+
+        return sourceFile.nameTable;
+    }
+
+    function initializeNameTable(sourceFile: SourceFile): void {
+        var nameTable: Map<string> = {};
+
+        walk(sourceFile);
+        sourceFile.nameTable = nameTable;
+
+        function walk(node: Node) {
+            switch (node.kind) {
+                case SyntaxKind.Identifier:
+                    nameTable[(<Identifier>node).text] = (<Identifier>node).text;
+                    break;
+                case SyntaxKind.StringLiteral:
+                case SyntaxKind.NumericLiteral:
+                    // We want to store any numbers/strings if they were a name that could be
+                    // related to a declaration.  So, if we have 'import x = require("something")'
+                    // then we want 'something' to be in the name table.  Similarly, if we have
+                    // "a['propname']" then we want to store "propname" in the name table.
+                    if (isDeclarationName(node) ||
+                        node.parent.kind === SyntaxKind.ExternalModuleReference ||
+                        isArgumentOfElementAccessExpression(node)) {
+
+                        nameTable[(<LiteralExpression>node).text] = (<LiteralExpression>node).text;
+                    }
+                    break;
+                default:
+                    forEachChild(node, walk);
+            }
+        }
+    }
+
+    function isArgumentOfElementAccessExpression(node: Node) {
+        return node &&
+            node.parent &&
+            node.parent.kind === SyntaxKind.ElementAccessExpression &&
+            (<ElementAccessExpression>node.parent).argumentExpression === node;
+    }
+
     /// Classifier
     export function createClassifier(): Classifier {
         var scanner = createScanner(ScriptTarget.Latest, /*skipTrivia*/ false);

src/services/signatureHelp.ts

@@ -295,8 +295,8 @@ module ts.SignatureHelp {
                 var tagExpression = <TaggedTemplateExpression>templateExpression.parent;
                 Debug.assert(templateExpression.kind === SyntaxKind.TemplateExpression);
 
-                // If we're just after a template tail, don't show signature help.
-                if (node.kind === SyntaxKind.TemplateTail && !isInsideTemplateLiteral(<LiteralExpression>node, position)) {
+                // If we're just after a template tail, don't show signature help.
+                if (node.kind === SyntaxKind.TemplateTail && !isInsideTemplateLiteral(<LiteralExpression>node, position)) {
                     return undefined;
                 }
 

tests/baselines/reference/APISample_compile.js

@@ -161,28 +161,28 @@ declare module "typescript" {
         WhileKeyword = 99,
         WithKeyword = 100,
         AsKeyword = 101,
-        FromKeyword = 102,
-        ImplementsKeyword = 103,
-        InterfaceKeyword = 104,
-        LetKeyword = 105,
-        PackageKeyword = 106,
-        PrivateKeyword = 107,
-        ProtectedKeyword = 108,
-        PublicKeyword = 109,
-        StaticKeyword = 110,
-        YieldKeyword = 111,
-        AnyKeyword = 112,
-        BooleanKeyword = 113,
-        ConstructorKeyword = 114,
-        DeclareKeyword = 115,
-        GetKeyword = 116,
-        ModuleKeyword = 117,
-        RequireKeyword = 118,
-        NumberKeyword = 119,
-        SetKeyword = 120,
-        StringKeyword = 121,
-        SymbolKeyword = 122,
-        TypeKeyword = 123,
+        ImplementsKeyword = 102,
+        InterfaceKeyword = 103,
+        LetKeyword = 104,
+        PackageKeyword = 105,
+        PrivateKeyword = 106,
+        ProtectedKeyword = 107,
+        PublicKeyword = 108,
+        StaticKeyword = 109,
+        YieldKeyword = 110,
+        AnyKeyword = 111,
+        BooleanKeyword = 112,
+        ConstructorKeyword = 113,
+        DeclareKeyword = 114,
+        GetKeyword = 115,
+        ModuleKeyword = 116,
+        RequireKeyword = 117,
+        NumberKeyword = 118,
+        SetKeyword = 119,
+        StringKeyword = 120,
+        SymbolKeyword = 121,
+        TypeKeyword = 122,
+        FromKeyword = 123,
         OfKeyword = 124,
         QualifiedName = 125,
         ComputedPropertyName = 126,
@@ -288,8 +288,8 @@ declare module "typescript" {
         LastReservedWord = 100,
         FirstKeyword = 65,
         LastKeyword = 124,
-        FirstFutureReservedWord = 103,
-        LastFutureReservedWord = 111,
+        FirstFutureReservedWord = 102,
+        LastFutureReservedWord = 110,
         FirstTypeNode = 139,
         LastTypeNode = 147,
         FirstPunctuation = 14,
@@ -673,9 +673,8 @@ declare module "typescript" {
         catchClause?: CatchClause;
         finallyBlock?: Block;
     }
-    interface CatchClause extends Declaration {
-        name: Identifier;
-        type?: TypeNode;
+    interface CatchClause extends Node {
+        variableDeclaration: VariableDeclaration;
         block: Block;
     }
     interface ModuleElement extends Node {
@@ -941,6 +940,7 @@ declare module "typescript" {
         isEntityNameVisible(entityName: EntityName, enclosingDeclaration: Node): SymbolVisibilityResult;
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         isUnknownIdentifier(location: Node, name: string): boolean;
+        getBlockScopedVariableId(node: Identifier): number;
     }
     const enum SymbolFlags {
         FunctionScopedVariable = 1,
@@ -1045,6 +1045,7 @@ declare module "typescript" {
         SuperStatic = 32,
         ContextChecked = 64,
         EnumValuesComputed = 128,
+        BlockScopedBindingInLoop = 256,
     }
     interface NodeLinks {
         resolvedType?: Type;
@@ -1517,9 +1518,6 @@ declare module "typescript" {
         getDocumentationComment(): SymbolDisplayPart[];
     }
     interface SourceFile {
-        version: string;
-        scriptSnapshot: IScriptSnapshot;
-        nameTable: Map<string>;
         getNamedDeclarations(): Declaration[];
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
         getLineStarts(): number[];
@@ -1873,25 +1871,17 @@ declare module "typescript" {
         acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Informs the DocumentRegistry that a file is not needed any longer.
           *

tests/baselines/reference/APISample_compile.types

@@ -501,72 +501,72 @@ declare module "typescript" {
         AsKeyword = 101,
 >AsKeyword : SyntaxKind
 
-        FromKeyword = 102,
->FromKeyword : SyntaxKind
-
-        ImplementsKeyword = 103,
+        ImplementsKeyword = 102,
 >ImplementsKeyword : SyntaxKind
 
-        InterfaceKeyword = 104,
+        InterfaceKeyword = 103,
 >InterfaceKeyword : SyntaxKind
 
-        LetKeyword = 105,
+        LetKeyword = 104,
 >LetKeyword : SyntaxKind
 
-        PackageKeyword = 106,
+        PackageKeyword = 105,
 >PackageKeyword : SyntaxKind
 
-        PrivateKeyword = 107,
+        PrivateKeyword = 106,
 >PrivateKeyword : SyntaxKind
 
-        ProtectedKeyword = 108,
+        ProtectedKeyword = 107,
 >ProtectedKeyword : SyntaxKind
 
-        PublicKeyword = 109,
+        PublicKeyword = 108,
 >PublicKeyword : SyntaxKind
 
-        StaticKeyword = 110,
+        StaticKeyword = 109,
 >StaticKeyword : SyntaxKind
 
-        YieldKeyword = 111,
+        YieldKeyword = 110,
 >YieldKeyword : SyntaxKind
 
-        AnyKeyword = 112,
+        AnyKeyword = 111,
 >AnyKeyword : SyntaxKind
 
-        BooleanKeyword = 113,
+        BooleanKeyword = 112,
 >BooleanKeyword : SyntaxKind
 
-        ConstructorKeyword = 114,
+        ConstructorKeyword = 113,
 >ConstructorKeyword : SyntaxKind
 
-        DeclareKeyword = 115,
+        DeclareKeyword = 114,
 >DeclareKeyword : SyntaxKind
 
-        GetKeyword = 116,
+        GetKeyword = 115,
 >GetKeyword : SyntaxKind
 
-        ModuleKeyword = 117,
+        ModuleKeyword = 116,
 >ModuleKeyword : SyntaxKind
 
-        RequireKeyword = 118,
+        RequireKeyword = 117,
 >RequireKeyword : SyntaxKind
 
-        NumberKeyword = 119,
+        NumberKeyword = 118,
 >NumberKeyword : SyntaxKind
 
-        SetKeyword = 120,
+        SetKeyword = 119,
 >SetKeyword : SyntaxKind
 
-        StringKeyword = 121,
+        StringKeyword = 120,
 >StringKeyword : SyntaxKind
 
-        SymbolKeyword = 122,
+        SymbolKeyword = 121,
 >SymbolKeyword : SyntaxKind
 
-        TypeKeyword = 123,
+        TypeKeyword = 122,
 >TypeKeyword : SyntaxKind
 
+        FromKeyword = 123,
+>FromKeyword : SyntaxKind
+
         OfKeyword = 124,
 >OfKeyword : SyntaxKind
 
@@ -882,10 +882,10 @@ declare module "typescript" {
         LastKeyword = 124,
 >LastKeyword : SyntaxKind
 
-        FirstFutureReservedWord = 103,
+        FirstFutureReservedWord = 102,
 >FirstFutureReservedWord : SyntaxKind
 
-        LastFutureReservedWord = 111,
+        LastFutureReservedWord = 110,
 >LastFutureReservedWord : SyntaxKind
 
         FirstTypeNode = 139,
@@ -2030,17 +2030,13 @@ declare module "typescript" {
 >finallyBlock : Block
 >Block : Block
     }
-    interface CatchClause extends Declaration {
+    interface CatchClause extends Node {
 >CatchClause : CatchClause
->Declaration : Declaration
+>Node : Node
 
-        name: Identifier;
->name : Identifier
->Identifier : Identifier
-
-        type?: TypeNode;
->type : TypeNode
->TypeNode : TypeNode
+        variableDeclaration: VariableDeclaration;
+>variableDeclaration : VariableDeclaration
+>VariableDeclaration : VariableDeclaration
 
         block: Block;
 >block : Block
@@ -3063,6 +3059,11 @@ declare module "typescript" {
 >location : Node
 >Node : Node
 >name : string
+
+        getBlockScopedVariableId(node: Identifier): number;
+>getBlockScopedVariableId : (node: Identifier) => number
+>node : Identifier
+>Identifier : Identifier
     }
     const enum SymbolFlags {
 >SymbolFlags : SymbolFlags
@@ -3374,6 +3375,9 @@ declare module "typescript" {
 
         EnumValuesComputed = 128,
 >EnumValuesComputed : NodeCheckFlags
+
+        BlockScopedBindingInLoop = 256,
+>BlockScopedBindingInLoop : NodeCheckFlags
     }
     interface NodeLinks {
 >NodeLinks : NodeLinks
@@ -4892,17 +4896,6 @@ declare module "typescript" {
     interface SourceFile {
 >SourceFile : SourceFile
 
-        version: string;
->version : string
-
-        scriptSnapshot: IScriptSnapshot;
->scriptSnapshot : IScriptSnapshot
->IScriptSnapshot : IScriptSnapshot
-
-        nameTable: Map<string>;
->nameTable : Map<string>
->Map : Map<T>
-
         getNamedDeclarations(): Declaration[];
 >getNamedDeclarations : () => Declaration[]
 >Declaration : Declaration
@@ -5853,36 +5846,24 @@ declare module "typescript" {
 
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
->updateDocument : (sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange) => SourceFile
->sourceFile : SourceFile
->SourceFile : SourceFile
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
+>updateDocument : (fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string) => SourceFile
 >fileName : string
 >compilationSettings : CompilerOptions
 >CompilerOptions : CompilerOptions
 >scriptSnapshot : IScriptSnapshot
 >IScriptSnapshot : IScriptSnapshot
 >version : string
->textChangeRange : TextChangeRange
->TextChangeRange : TextChangeRange
 >SourceFile : SourceFile
 
         /**

tests/baselines/reference/APISample_linter.js

@@ -192,28 +192,28 @@ declare module "typescript" {
         WhileKeyword = 99,
         WithKeyword = 100,
         AsKeyword = 101,
-        FromKeyword = 102,
-        ImplementsKeyword = 103,
-        InterfaceKeyword = 104,
-        LetKeyword = 105,
-        PackageKeyword = 106,
-        PrivateKeyword = 107,
-        ProtectedKeyword = 108,
-        PublicKeyword = 109,
-        StaticKeyword = 110,
-        YieldKeyword = 111,
-        AnyKeyword = 112,
-        BooleanKeyword = 113,
-        ConstructorKeyword = 114,
-        DeclareKeyword = 115,
-        GetKeyword = 116,
-        ModuleKeyword = 117,
-        RequireKeyword = 118,
-        NumberKeyword = 119,
-        SetKeyword = 120,
-        StringKeyword = 121,
-        SymbolKeyword = 122,
-        TypeKeyword = 123,
+        ImplementsKeyword = 102,
+        InterfaceKeyword = 103,
+        LetKeyword = 104,
+        PackageKeyword = 105,
+        PrivateKeyword = 106,
+        ProtectedKeyword = 107,
+        PublicKeyword = 108,
+        StaticKeyword = 109,
+        YieldKeyword = 110,
+        AnyKeyword = 111,
+        BooleanKeyword = 112,
+        ConstructorKeyword = 113,
+        DeclareKeyword = 114,
+        GetKeyword = 115,
+        ModuleKeyword = 116,
+        RequireKeyword = 117,
+        NumberKeyword = 118,
+        SetKeyword = 119,
+        StringKeyword = 120,
+        SymbolKeyword = 121,
+        TypeKeyword = 122,
+        FromKeyword = 123,
         OfKeyword = 124,
         QualifiedName = 125,
         ComputedPropertyName = 126,
@@ -319,8 +319,8 @@ declare module "typescript" {
         LastReservedWord = 100,
         FirstKeyword = 65,
         LastKeyword = 124,
-        FirstFutureReservedWord = 103,
-        LastFutureReservedWord = 111,
+        FirstFutureReservedWord = 102,
+        LastFutureReservedWord = 110,
         FirstTypeNode = 139,
         LastTypeNode = 147,
         FirstPunctuation = 14,
@@ -704,9 +704,8 @@ declare module "typescript" {
         catchClause?: CatchClause;
         finallyBlock?: Block;
     }
-    interface CatchClause extends Declaration {
-        name: Identifier;
-        type?: TypeNode;
+    interface CatchClause extends Node {
+        variableDeclaration: VariableDeclaration;
         block: Block;
     }
     interface ModuleElement extends Node {
@@ -972,6 +971,7 @@ declare module "typescript" {
         isEntityNameVisible(entityName: EntityName, enclosingDeclaration: Node): SymbolVisibilityResult;
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         isUnknownIdentifier(location: Node, name: string): boolean;
+        getBlockScopedVariableId(node: Identifier): number;
     }
     const enum SymbolFlags {
         FunctionScopedVariable = 1,
@@ -1076,6 +1076,7 @@ declare module "typescript" {
         SuperStatic = 32,
         ContextChecked = 64,
         EnumValuesComputed = 128,
+        BlockScopedBindingInLoop = 256,
     }
     interface NodeLinks {
         resolvedType?: Type;
@@ -1548,9 +1549,6 @@ declare module "typescript" {
         getDocumentationComment(): SymbolDisplayPart[];
     }
     interface SourceFile {
-        version: string;
-        scriptSnapshot: IScriptSnapshot;
-        nameTable: Map<string>;
         getNamedDeclarations(): Declaration[];
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
         getLineStarts(): number[];
@@ -1904,25 +1902,17 @@ declare module "typescript" {
         acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Informs the DocumentRegistry that a file is not needed any longer.
           *

tests/baselines/reference/APISample_linter.types

@@ -647,72 +647,72 @@ declare module "typescript" {
         AsKeyword = 101,
 >AsKeyword : SyntaxKind
 
-        FromKeyword = 102,
->FromKeyword : SyntaxKind
-
-        ImplementsKeyword = 103,
+        ImplementsKeyword = 102,
 >ImplementsKeyword : SyntaxKind
 
-        InterfaceKeyword = 104,
+        InterfaceKeyword = 103,
 >InterfaceKeyword : SyntaxKind
 
-        LetKeyword = 105,
+        LetKeyword = 104,
 >LetKeyword : SyntaxKind
 
-        PackageKeyword = 106,
+        PackageKeyword = 105,
 >PackageKeyword : SyntaxKind
 
-        PrivateKeyword = 107,
+        PrivateKeyword = 106,
 >PrivateKeyword : SyntaxKind
 
-        ProtectedKeyword = 108,
+        ProtectedKeyword = 107,
 >ProtectedKeyword : SyntaxKind
 
-        PublicKeyword = 109,
+        PublicKeyword = 108,
 >PublicKeyword : SyntaxKind
 
-        StaticKeyword = 110,
+        StaticKeyword = 109,
 >StaticKeyword : SyntaxKind
 
-        YieldKeyword = 111,
+        YieldKeyword = 110,
 >YieldKeyword : SyntaxKind
 
-        AnyKeyword = 112,
+        AnyKeyword = 111,
 >AnyKeyword : SyntaxKind
 
-        BooleanKeyword = 113,
+        BooleanKeyword = 112,
 >BooleanKeyword : SyntaxKind
 
-        ConstructorKeyword = 114,
+        ConstructorKeyword = 113,
 >ConstructorKeyword : SyntaxKind
 
-        DeclareKeyword = 115,
+        DeclareKeyword = 114,
 >DeclareKeyword : SyntaxKind
 
-        GetKeyword = 116,
+        GetKeyword = 115,
 >GetKeyword : SyntaxKind
 
-        ModuleKeyword = 117,
+        ModuleKeyword = 116,
 >ModuleKeyword : SyntaxKind
 
-        RequireKeyword = 118,
+        RequireKeyword = 117,
 >RequireKeyword : SyntaxKind
 
-        NumberKeyword = 119,
+        NumberKeyword = 118,
 >NumberKeyword : SyntaxKind
 
-        SetKeyword = 120,
+        SetKeyword = 119,
 >SetKeyword : SyntaxKind
 
-        StringKeyword = 121,
+        StringKeyword = 120,
 >StringKeyword : SyntaxKind
 
-        SymbolKeyword = 122,
+        SymbolKeyword = 121,
 >SymbolKeyword : SyntaxKind
 
-        TypeKeyword = 123,
+        TypeKeyword = 122,
 >TypeKeyword : SyntaxKind
 
+        FromKeyword = 123,
+>FromKeyword : SyntaxKind
+
         OfKeyword = 124,
 >OfKeyword : SyntaxKind
 
@@ -1028,10 +1028,10 @@ declare module "typescript" {
         LastKeyword = 124,
 >LastKeyword : SyntaxKind
 
-        FirstFutureReservedWord = 103,
+        FirstFutureReservedWord = 102,
 >FirstFutureReservedWord : SyntaxKind
 
-        LastFutureReservedWord = 111,
+        LastFutureReservedWord = 110,
 >LastFutureReservedWord : SyntaxKind
 
         FirstTypeNode = 139,
@@ -2176,17 +2176,13 @@ declare module "typescript" {
 >finallyBlock : Block
 >Block : Block
     }
-    interface CatchClause extends Declaration {
+    interface CatchClause extends Node {
 >CatchClause : CatchClause
->Declaration : Declaration
+>Node : Node
 
-        name: Identifier;
->name : Identifier
->Identifier : Identifier
-
-        type?: TypeNode;
->type : TypeNode
->TypeNode : TypeNode
+        variableDeclaration: VariableDeclaration;
+>variableDeclaration : VariableDeclaration
+>VariableDeclaration : VariableDeclaration
 
         block: Block;
 >block : Block
@@ -3209,6 +3205,11 @@ declare module "typescript" {
 >location : Node
 >Node : Node
 >name : string
+
+        getBlockScopedVariableId(node: Identifier): number;
+>getBlockScopedVariableId : (node: Identifier) => number
+>node : Identifier
+>Identifier : Identifier
     }
     const enum SymbolFlags {
 >SymbolFlags : SymbolFlags
@@ -3520,6 +3521,9 @@ declare module "typescript" {
 
         EnumValuesComputed = 128,
 >EnumValuesComputed : NodeCheckFlags
+
+        BlockScopedBindingInLoop = 256,
+>BlockScopedBindingInLoop : NodeCheckFlags
     }
     interface NodeLinks {
 >NodeLinks : NodeLinks
@@ -5038,17 +5042,6 @@ declare module "typescript" {
     interface SourceFile {
 >SourceFile : SourceFile
 
-        version: string;
->version : string
-
-        scriptSnapshot: IScriptSnapshot;
->scriptSnapshot : IScriptSnapshot
->IScriptSnapshot : IScriptSnapshot
-
-        nameTable: Map<string>;
->nameTable : Map<string>
->Map : Map<T>
-
         getNamedDeclarations(): Declaration[];
 >getNamedDeclarations : () => Declaration[]
 >Declaration : Declaration
@@ -5999,36 +5992,24 @@ declare module "typescript" {
 
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
->updateDocument : (sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange) => SourceFile
->sourceFile : SourceFile
->SourceFile : SourceFile
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
+>updateDocument : (fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string) => SourceFile
 >fileName : string
 >compilationSettings : CompilerOptions
 >CompilerOptions : CompilerOptions
 >scriptSnapshot : IScriptSnapshot
 >IScriptSnapshot : IScriptSnapshot
 >version : string
->textChangeRange : TextChangeRange
->TextChangeRange : TextChangeRange
 >SourceFile : SourceFile
 
         /**

tests/baselines/reference/APISample_transform.js

@@ -193,28 +193,28 @@ declare module "typescript" {
         WhileKeyword = 99,
         WithKeyword = 100,
         AsKeyword = 101,
-        FromKeyword = 102,
-        ImplementsKeyword = 103,
-        InterfaceKeyword = 104,
-        LetKeyword = 105,
-        PackageKeyword = 106,
-        PrivateKeyword = 107,
-        ProtectedKeyword = 108,
-        PublicKeyword = 109,
-        StaticKeyword = 110,
-        YieldKeyword = 111,
-        AnyKeyword = 112,
-        BooleanKeyword = 113,
-        ConstructorKeyword = 114,
-        DeclareKeyword = 115,
-        GetKeyword = 116,
-        ModuleKeyword = 117,
-        RequireKeyword = 118,
-        NumberKeyword = 119,
-        SetKeyword = 120,
-        StringKeyword = 121,
-        SymbolKeyword = 122,
-        TypeKeyword = 123,
+        ImplementsKeyword = 102,
+        InterfaceKeyword = 103,
+        LetKeyword = 104,
+        PackageKeyword = 105,
+        PrivateKeyword = 106,
+        ProtectedKeyword = 107,
+        PublicKeyword = 108,
+        StaticKeyword = 109,
+        YieldKeyword = 110,
+        AnyKeyword = 111,
+        BooleanKeyword = 112,
+        ConstructorKeyword = 113,
+        DeclareKeyword = 114,
+        GetKeyword = 115,
+        ModuleKeyword = 116,
+        RequireKeyword = 117,
+        NumberKeyword = 118,
+        SetKeyword = 119,
+        StringKeyword = 120,
+        SymbolKeyword = 121,
+        TypeKeyword = 122,
+        FromKeyword = 123,
         OfKeyword = 124,
         QualifiedName = 125,
         ComputedPropertyName = 126,
@@ -320,8 +320,8 @@ declare module "typescript" {
         LastReservedWord = 100,
         FirstKeyword = 65,
         LastKeyword = 124,
-        FirstFutureReservedWord = 103,
-        LastFutureReservedWord = 111,
+        FirstFutureReservedWord = 102,
+        LastFutureReservedWord = 110,
         FirstTypeNode = 139,
         LastTypeNode = 147,
         FirstPunctuation = 14,
@@ -705,9 +705,8 @@ declare module "typescript" {
         catchClause?: CatchClause;
         finallyBlock?: Block;
     }
-    interface CatchClause extends Declaration {
-        name: Identifier;
-        type?: TypeNode;
+    interface CatchClause extends Node {
+        variableDeclaration: VariableDeclaration;
         block: Block;
     }
     interface ModuleElement extends Node {
@@ -973,6 +972,7 @@ declare module "typescript" {
         isEntityNameVisible(entityName: EntityName, enclosingDeclaration: Node): SymbolVisibilityResult;
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         isUnknownIdentifier(location: Node, name: string): boolean;
+        getBlockScopedVariableId(node: Identifier): number;
     }
     const enum SymbolFlags {
         FunctionScopedVariable = 1,
@@ -1077,6 +1077,7 @@ declare module "typescript" {
         SuperStatic = 32,
         ContextChecked = 64,
         EnumValuesComputed = 128,
+        BlockScopedBindingInLoop = 256,
     }
     interface NodeLinks {
         resolvedType?: Type;
@@ -1549,9 +1550,6 @@ declare module "typescript" {
         getDocumentationComment(): SymbolDisplayPart[];
     }
     interface SourceFile {
-        version: string;
-        scriptSnapshot: IScriptSnapshot;
-        nameTable: Map<string>;
         getNamedDeclarations(): Declaration[];
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
         getLineStarts(): number[];
@@ -1905,25 +1903,17 @@ declare module "typescript" {
         acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Informs the DocumentRegistry that a file is not needed any longer.
           *

tests/baselines/reference/APISample_transform.types

@@ -597,72 +597,72 @@ declare module "typescript" {
         AsKeyword = 101,
 >AsKeyword : SyntaxKind
 
-        FromKeyword = 102,
->FromKeyword : SyntaxKind
-
-        ImplementsKeyword = 103,
+        ImplementsKeyword = 102,
 >ImplementsKeyword : SyntaxKind
 
-        InterfaceKeyword = 104,
+        InterfaceKeyword = 103,
 >InterfaceKeyword : SyntaxKind
 
-        LetKeyword = 105,
+        LetKeyword = 104,
 >LetKeyword : SyntaxKind
 
-        PackageKeyword = 106,
+        PackageKeyword = 105,
 >PackageKeyword : SyntaxKind
 
-        PrivateKeyword = 107,
+        PrivateKeyword = 106,
 >PrivateKeyword : SyntaxKind
 
-        ProtectedKeyword = 108,
+        ProtectedKeyword = 107,
 >ProtectedKeyword : SyntaxKind
 
-        PublicKeyword = 109,
+        PublicKeyword = 108,
 >PublicKeyword : SyntaxKind
 
-        StaticKeyword = 110,
+        StaticKeyword = 109,
 >StaticKeyword : SyntaxKind
 
-        YieldKeyword = 111,
+        YieldKeyword = 110,
 >YieldKeyword : SyntaxKind
 
-        AnyKeyword = 112,
+        AnyKeyword = 111,
 >AnyKeyword : SyntaxKind
 
-        BooleanKeyword = 113,
+        BooleanKeyword = 112,
 >BooleanKeyword : SyntaxKind
 
-        ConstructorKeyword = 114,
+        ConstructorKeyword = 113,
 >ConstructorKeyword : SyntaxKind
 
-        DeclareKeyword = 115,
+        DeclareKeyword = 114,
 >DeclareKeyword : SyntaxKind
 
-        GetKeyword = 116,
+        GetKeyword = 115,
 >GetKeyword : SyntaxKind
 
-        ModuleKeyword = 117,
+        ModuleKeyword = 116,
 >ModuleKeyword : SyntaxKind
 
-        RequireKeyword = 118,
+        RequireKeyword = 117,
 >RequireKeyword : SyntaxKind
 
-        NumberKeyword = 119,
+        NumberKeyword = 118,
 >NumberKeyword : SyntaxKind
 
-        SetKeyword = 120,
+        SetKeyword = 119,
 >SetKeyword : SyntaxKind
 
-        StringKeyword = 121,
+        StringKeyword = 120,
 >StringKeyword : SyntaxKind
 
-        SymbolKeyword = 122,
+        SymbolKeyword = 121,
 >SymbolKeyword : SyntaxKind
 
-        TypeKeyword = 123,
+        TypeKeyword = 122,
 >TypeKeyword : SyntaxKind
 
+        FromKeyword = 123,
+>FromKeyword : SyntaxKind
+
         OfKeyword = 124,
 >OfKeyword : SyntaxKind
 
@@ -978,10 +978,10 @@ declare module "typescript" {
         LastKeyword = 124,
 >LastKeyword : SyntaxKind
 
-        FirstFutureReservedWord = 103,
+        FirstFutureReservedWord = 102,
 >FirstFutureReservedWord : SyntaxKind
 
-        LastFutureReservedWord = 111,
+        LastFutureReservedWord = 110,
 >LastFutureReservedWord : SyntaxKind
 
         FirstTypeNode = 139,
@@ -2126,17 +2126,13 @@ declare module "typescript" {
 >finallyBlock : Block
 >Block : Block
     }
-    interface CatchClause extends Declaration {
+    interface CatchClause extends Node {
 >CatchClause : CatchClause
->Declaration : Declaration
+>Node : Node
 
-        name: Identifier;
->name : Identifier
->Identifier : Identifier
-
-        type?: TypeNode;
->type : TypeNode
->TypeNode : TypeNode
+        variableDeclaration: VariableDeclaration;
+>variableDeclaration : VariableDeclaration
+>VariableDeclaration : VariableDeclaration
 
         block: Block;
 >block : Block
@@ -3159,6 +3155,11 @@ declare module "typescript" {
 >location : Node
 >Node : Node
 >name : string
+
+        getBlockScopedVariableId(node: Identifier): number;
+>getBlockScopedVariableId : (node: Identifier) => number
+>node : Identifier
+>Identifier : Identifier
     }
     const enum SymbolFlags {
 >SymbolFlags : SymbolFlags
@@ -3470,6 +3471,9 @@ declare module "typescript" {
 
         EnumValuesComputed = 128,
 >EnumValuesComputed : NodeCheckFlags
+
+        BlockScopedBindingInLoop = 256,
+>BlockScopedBindingInLoop : NodeCheckFlags
     }
     interface NodeLinks {
 >NodeLinks : NodeLinks
@@ -4988,17 +4992,6 @@ declare module "typescript" {
     interface SourceFile {
 >SourceFile : SourceFile
 
-        version: string;
->version : string
-
-        scriptSnapshot: IScriptSnapshot;
->scriptSnapshot : IScriptSnapshot
->IScriptSnapshot : IScriptSnapshot
-
-        nameTable: Map<string>;
->nameTable : Map<string>
->Map : Map<T>
-
         getNamedDeclarations(): Declaration[];
 >getNamedDeclarations : () => Declaration[]
 >Declaration : Declaration
@@ -5949,36 +5942,24 @@ declare module "typescript" {
 
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
->updateDocument : (sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange) => SourceFile
->sourceFile : SourceFile
->SourceFile : SourceFile
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
+>updateDocument : (fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string) => SourceFile
 >fileName : string
 >compilationSettings : CompilerOptions
 >CompilerOptions : CompilerOptions
 >scriptSnapshot : IScriptSnapshot
 >IScriptSnapshot : IScriptSnapshot
 >version : string
->textChangeRange : TextChangeRange
->TextChangeRange : TextChangeRange
 >SourceFile : SourceFile
 
         /**

tests/baselines/reference/APISample_watcher.js

@@ -230,28 +230,28 @@ declare module "typescript" {
         WhileKeyword = 99,
         WithKeyword = 100,
         AsKeyword = 101,
-        FromKeyword = 102,
-        ImplementsKeyword = 103,
-        InterfaceKeyword = 104,
-        LetKeyword = 105,
-        PackageKeyword = 106,
-        PrivateKeyword = 107,
-        ProtectedKeyword = 108,
-        PublicKeyword = 109,
-        StaticKeyword = 110,
-        YieldKeyword = 111,
-        AnyKeyword = 112,
-        BooleanKeyword = 113,
-        ConstructorKeyword = 114,
-        DeclareKeyword = 115,
-        GetKeyword = 116,
-        ModuleKeyword = 117,
-        RequireKeyword = 118,
-        NumberKeyword = 119,
-        SetKeyword = 120,
-        StringKeyword = 121,
-        SymbolKeyword = 122,
-        TypeKeyword = 123,
+        ImplementsKeyword = 102,
+        InterfaceKeyword = 103,
+        LetKeyword = 104,
+        PackageKeyword = 105,
+        PrivateKeyword = 106,
+        ProtectedKeyword = 107,
+        PublicKeyword = 108,
+        StaticKeyword = 109,
+        YieldKeyword = 110,
+        AnyKeyword = 111,
+        BooleanKeyword = 112,
+        ConstructorKeyword = 113,
+        DeclareKeyword = 114,
+        GetKeyword = 115,
+        ModuleKeyword = 116,
+        RequireKeyword = 117,
+        NumberKeyword = 118,
+        SetKeyword = 119,
+        StringKeyword = 120,
+        SymbolKeyword = 121,
+        TypeKeyword = 122,
+        FromKeyword = 123,
         OfKeyword = 124,
         QualifiedName = 125,
         ComputedPropertyName = 126,
@@ -357,8 +357,8 @@ declare module "typescript" {
         LastReservedWord = 100,
         FirstKeyword = 65,
         LastKeyword = 124,
-        FirstFutureReservedWord = 103,
-        LastFutureReservedWord = 111,
+        FirstFutureReservedWord = 102,
+        LastFutureReservedWord = 110,
         FirstTypeNode = 139,
         LastTypeNode = 147,
         FirstPunctuation = 14,
@@ -742,9 +742,8 @@ declare module "typescript" {
         catchClause?: CatchClause;
         finallyBlock?: Block;
     }
-    interface CatchClause extends Declaration {
-        name: Identifier;
-        type?: TypeNode;
+    interface CatchClause extends Node {
+        variableDeclaration: VariableDeclaration;
         block: Block;
     }
     interface ModuleElement extends Node {
@@ -1010,6 +1009,7 @@ declare module "typescript" {
         isEntityNameVisible(entityName: EntityName, enclosingDeclaration: Node): SymbolVisibilityResult;
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         isUnknownIdentifier(location: Node, name: string): boolean;
+        getBlockScopedVariableId(node: Identifier): number;
     }
     const enum SymbolFlags {
         FunctionScopedVariable = 1,
@@ -1114,6 +1114,7 @@ declare module "typescript" {
         SuperStatic = 32,
         ContextChecked = 64,
         EnumValuesComputed = 128,
+        BlockScopedBindingInLoop = 256,
     }
     interface NodeLinks {
         resolvedType?: Type;
@@ -1586,9 +1587,6 @@ declare module "typescript" {
         getDocumentationComment(): SymbolDisplayPart[];
     }
     interface SourceFile {
-        version: string;
-        scriptSnapshot: IScriptSnapshot;
-        nameTable: Map<string>;
         getNamedDeclarations(): Declaration[];
         getLineAndCharacterOfPosition(pos: number): LineAndCharacter;
         getLineStarts(): number[];
@@ -1942,25 +1940,17 @@ declare module "typescript" {
         acquireDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
         /**
           * Informs the DocumentRegistry that a file is not needed any longer.
           *

tests/baselines/reference/APISample_watcher.types

@@ -770,72 +770,72 @@ declare module "typescript" {
         AsKeyword = 101,
 >AsKeyword : SyntaxKind
 
-        FromKeyword = 102,
->FromKeyword : SyntaxKind
-
-        ImplementsKeyword = 103,
+        ImplementsKeyword = 102,
 >ImplementsKeyword : SyntaxKind
 
-        InterfaceKeyword = 104,
+        InterfaceKeyword = 103,
 >InterfaceKeyword : SyntaxKind
 
-        LetKeyword = 105,
+        LetKeyword = 104,
 >LetKeyword : SyntaxKind
 
-        PackageKeyword = 106,
+        PackageKeyword = 105,
 >PackageKeyword : SyntaxKind
 
-        PrivateKeyword = 107,
+        PrivateKeyword = 106,
 >PrivateKeyword : SyntaxKind
 
-        ProtectedKeyword = 108,
+        ProtectedKeyword = 107,
 >ProtectedKeyword : SyntaxKind
 
-        PublicKeyword = 109,
+        PublicKeyword = 108,
 >PublicKeyword : SyntaxKind
 
-        StaticKeyword = 110,
+        StaticKeyword = 109,
 >StaticKeyword : SyntaxKind
 
-        YieldKeyword = 111,
+        YieldKeyword = 110,
 >YieldKeyword : SyntaxKind
 
-        AnyKeyword = 112,
+        AnyKeyword = 111,
 >AnyKeyword : SyntaxKind
 
-        BooleanKeyword = 113,
+        BooleanKeyword = 112,
 >BooleanKeyword : SyntaxKind
 
-        ConstructorKeyword = 114,
+        ConstructorKeyword = 113,
 >ConstructorKeyword : SyntaxKind
 
-        DeclareKeyword = 115,
+        DeclareKeyword = 114,
 >DeclareKeyword : SyntaxKind
 
-        GetKeyword = 116,
+        GetKeyword = 115,
 >GetKeyword : SyntaxKind
 
-        ModuleKeyword = 117,
+        ModuleKeyword = 116,
 >ModuleKeyword : SyntaxKind
 
-        RequireKeyword = 118,
+        RequireKeyword = 117,
 >RequireKeyword : SyntaxKind
 
-        NumberKeyword = 119,
+        NumberKeyword = 118,
 >NumberKeyword : SyntaxKind
 
-        SetKeyword = 120,
+        SetKeyword = 119,
 >SetKeyword : SyntaxKind
 
-        StringKeyword = 121,
+        StringKeyword = 120,
 >StringKeyword : SyntaxKind
 
-        SymbolKeyword = 122,
+        SymbolKeyword = 121,
 >SymbolKeyword : SyntaxKind
 
-        TypeKeyword = 123,
+        TypeKeyword = 122,
 >TypeKeyword : SyntaxKind
 
+        FromKeyword = 123,
+>FromKeyword : SyntaxKind
+
         OfKeyword = 124,
 >OfKeyword : SyntaxKind
 
@@ -1151,10 +1151,10 @@ declare module "typescript" {
         LastKeyword = 124,
 >LastKeyword : SyntaxKind
 
-        FirstFutureReservedWord = 103,
+        FirstFutureReservedWord = 102,
 >FirstFutureReservedWord : SyntaxKind
 
-        LastFutureReservedWord = 111,
+        LastFutureReservedWord = 110,
 >LastFutureReservedWord : SyntaxKind
 
         FirstTypeNode = 139,
@@ -2299,17 +2299,13 @@ declare module "typescript" {
 >finallyBlock : Block
 >Block : Block
     }
-    interface CatchClause extends Declaration {
+    interface CatchClause extends Node {
 >CatchClause : CatchClause
->Declaration : Declaration
+>Node : Node
 
-        name: Identifier;
->name : Identifier
->Identifier : Identifier
-
-        type?: TypeNode;
->type : TypeNode
->TypeNode : TypeNode
+        variableDeclaration: VariableDeclaration;
+>variableDeclaration : VariableDeclaration
+>VariableDeclaration : VariableDeclaration
 
         block: Block;
 >block : Block
@@ -3332,6 +3328,11 @@ declare module "typescript" {
 >location : Node
 >Node : Node
 >name : string
+
+        getBlockScopedVariableId(node: Identifier): number;
+>getBlockScopedVariableId : (node: Identifier) => number
+>node : Identifier
+>Identifier : Identifier
     }
     const enum SymbolFlags {
 >SymbolFlags : SymbolFlags
@@ -3643,6 +3644,9 @@ declare module "typescript" {
 
         EnumValuesComputed = 128,
 >EnumValuesComputed : NodeCheckFlags
+
+        BlockScopedBindingInLoop = 256,
+>BlockScopedBindingInLoop : NodeCheckFlags
     }
     interface NodeLinks {
 >NodeLinks : NodeLinks
@@ -5161,17 +5165,6 @@ declare module "typescript" {
     interface SourceFile {
 >SourceFile : SourceFile
 
-        version: string;
->version : string
-
-        scriptSnapshot: IScriptSnapshot;
->scriptSnapshot : IScriptSnapshot
->IScriptSnapshot : IScriptSnapshot
-
-        nameTable: Map<string>;
->nameTable : Map<string>
->Map : Map<T>
-
         getNamedDeclarations(): Declaration[];
 >getNamedDeclarations : () => Declaration[]
 >Declaration : Declaration
@@ -6122,36 +6115,24 @@ declare module "typescript" {
 
         /**
           * Request an updated version of an already existing SourceFile with a given fileName
-          * and compilationSettings. The update will intern call updateLanguageServiceSourceFile
+          * and compilationSettings. The update will in-turn call updateLanguageServiceSourceFile
           * to get an updated SourceFile.
           *
-          * Note: It is not allowed to call update on a SourceFile that was not acquired from this
-          * registry originally.
-          *
-          * @param sourceFile The original sourceFile object to update
           * @param fileName The name of the file requested
           * @param compilationSettings Some compilation settings like target affects the
           * shape of a the resulting SourceFile. This allows the DocumentRegistry to store
           * multiple copies of the same file for different compilation settings.
-          * @parm scriptSnapshot Text of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm version Current version of the file. Only used if the file was not found
-          * in the registry and a new one was created.
-          * @parm textChangeRange Change ranges since the last snapshot. Only used if the file
-          * was not found in the registry and a new one was created.
+          * @param scriptSnapshot Text of the file.
+          * @param version Current version of the file.
           */
-        updateDocument(sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange): SourceFile;
->updateDocument : (sourceFile: SourceFile, fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string, textChangeRange: TextChangeRange) => SourceFile
->sourceFile : SourceFile
->SourceFile : SourceFile
+        updateDocument(fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string): SourceFile;
+>updateDocument : (fileName: string, compilationSettings: CompilerOptions, scriptSnapshot: IScriptSnapshot, version: string) => SourceFile
 >fileName : string
 >compilationSettings : CompilerOptions
 >CompilerOptions : CompilerOptions
 >scriptSnapshot : IScriptSnapshot
 >IScriptSnapshot : IScriptSnapshot
 >version : string
->textChangeRange : TextChangeRange
->TextChangeRange : TextChangeRange
 >SourceFile : SourceFile
 
         /**

tests/baselines/reference/ES5SymbolProperty1.js

@@ -12,8 +12,8 @@ obj[Symbol.foo];
 
 //// [ES5SymbolProperty1.js]
 var Symbol;
-var obj = (_a = {}, _a[Symbol.foo] =
-    0,
+var obj = (_a = {},
+    _a[Symbol.foo] = 0,
     _a);
 obj[Symbol.foo];
 var _a;

tests/baselines/reference/FunctionDeclaration8_es6.js

@@ -2,7 +2,7 @@
 var v = { [yield]: foo }
 
 //// [FunctionDeclaration8_es6.js]
-var v = (_a = {}, _a[yield] =
-    foo,
+var v = (_a = {},
+    _a[yield] = foo,
     _a);
 var _a;

tests/baselines/reference/FunctionDeclaration9_es6.js

@@ -5,8 +5,8 @@ function * foo() {
 
 //// [FunctionDeclaration9_es6.js]
 function foo() {
-    var v = (_a = {}, _a[] =
-        foo,
+    var v = (_a = {},
+        _a[] = foo,
         _a);
     var _a;
 }

tests/baselines/reference/FunctionPropertyAssignments5_es6.js

@@ -2,6 +2,7 @@
 var v = { *[foo()]() { } }
 
 //// [FunctionPropertyAssignments5_es6.js]
-var v = (_a = {}, _a[foo()] = function () { },
+var v = (_a = {},
+    _a[foo()] = function () { },
     _a);
 var _a;

tests/baselines/reference/VariableDeclaration10_es6.errors.txt

@@ -1,7 +0,0 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration10_es6.ts(1,1): error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration10_es6.ts (1 errors) ====
-    let a: number = 1
-    ~~~
-!!! error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.

tests/baselines/reference/VariableDeclaration10_es6.types

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration10_es6.ts ===
+let a: number = 1
+>a : number
+

tests/baselines/reference/VariableDeclaration2_es6.errors.txt

@@ -1,10 +1,7 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration2_es6.ts(1,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
 tests/cases/conformance/es6/variableDeclarations/VariableDeclaration2_es6.ts(1,7): error TS1155: 'const' declarations must be initialized
 
 
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration2_es6.ts (2 errors) ====
+==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration2_es6.ts (1 errors) ====
     const a
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
           ~
 !!! error TS1155: 'const' declarations must be initialized

tests/baselines/reference/VariableDeclaration3_es6.errors.txt

@@ -1,7 +0,0 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration3_es6.ts(1,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration3_es6.ts (1 errors) ====
-    const a = 1
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.

tests/baselines/reference/VariableDeclaration3_es6.types

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration3_es6.ts ===
+const a = 1
+>a : number
+

tests/baselines/reference/VariableDeclaration4_es6.errors.txt

@@ -1,10 +1,7 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration4_es6.ts(1,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
 tests/cases/conformance/es6/variableDeclarations/VariableDeclaration4_es6.ts(1,7): error TS1155: 'const' declarations must be initialized
 
 
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration4_es6.ts (2 errors) ====
+==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration4_es6.ts (1 errors) ====
     const a: number
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
           ~
 !!! error TS1155: 'const' declarations must be initialized

tests/baselines/reference/VariableDeclaration5_es6.errors.txt

@@ -1,7 +0,0 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration5_es6.ts(1,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration5_es6.ts (1 errors) ====
-    const a: number = 1
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.

tests/baselines/reference/VariableDeclaration5_es6.types

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration5_es6.ts ===
+const a: number = 1
+>a : number
+

tests/baselines/reference/VariableDeclaration7_es6.errors.txt

@@ -1,7 +0,0 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration7_es6.ts(1,1): error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration7_es6.ts (1 errors) ====
-    let a
-    ~~~
-!!! error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.

tests/baselines/reference/VariableDeclaration7_es6.types

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration7_es6.ts ===
+let a
+>a : any
+

tests/baselines/reference/VariableDeclaration8_es6.errors.txt

@@ -1,7 +0,0 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration8_es6.ts(1,1): error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration8_es6.ts (1 errors) ====
-    let a = 1
-    ~~~
-!!! error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.

tests/baselines/reference/VariableDeclaration8_es6.types

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration8_es6.ts ===
+let a = 1
+>a : number
+

tests/baselines/reference/VariableDeclaration9_es6.errors.txt

@@ -1,7 +0,0 @@
-tests/cases/conformance/es6/variableDeclarations/VariableDeclaration9_es6.ts(1,1): error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration9_es6.ts (1 errors) ====
-    let a: number
-    ~~~
-!!! error TS1153: 'let' declarations are only available when targeting ECMAScript 6 and higher.

tests/baselines/reference/VariableDeclaration9_es6.types

@@ -0,0 +1,4 @@
+=== tests/cases/conformance/es6/variableDeclarations/VariableDeclaration9_es6.ts ===
+let a: number
+>a : number
+

tests/baselines/reference/bpSpan_stmts.baseline

@@ -217,7 +217,15 @@
     >:=> (line 28, col 8) to (line 28, col 22)
 29 >    } catch (e) {
 
-         ~~~~~~~~~~~~~                            => Pos: (416 to 428)  SpanInfo: {"start":437,"length":15}
+         ~~~~~~~~                                 => Pos: (416 to 423)  SpanInfo: {"start":437,"length":15}
+    >if (obj.z < 10)
+    >:=> (line 30, col 8) to (line 30, col 23)
+29 >    } catch (e) {
+
+                 ~                                => Pos: (424 to 424)  SpanInfo: undefined
+29 >    } catch (e) {
+
+                  ~~~~                            => Pos: (425 to 428)  SpanInfo: {"start":437,"length":15}
     >if (obj.z < 10)
     >:=> (line 30, col 8) to (line 30, col 23)
 --------------------------------
@@ -286,7 +294,15 @@
     >:=> (line 37, col 8) to (line 37, col 25)
 38 >    } catch (e1) {
 
-         ~~~~~~~~~~~~~~                           => Pos: (581 to 594)  SpanInfo: {"start":603,"length":10}
+         ~~~~~~~~                                 => Pos: (581 to 588)  SpanInfo: {"start":603,"length":10}
+    >var b = e1
+    >:=> (line 39, col 8) to (line 39, col 18)
+38 >    } catch (e1) {
+
+                 ~~                               => Pos: (589 to 590)  SpanInfo: undefined
+38 >    } catch (e1) {
+
+                   ~~~~                           => Pos: (591 to 594)  SpanInfo: {"start":603,"length":10}
     >var b = e1
     >:=> (line 39, col 8) to (line 39, col 18)
 --------------------------------

tests/baselines/reference/bpSpan_tryCatchFinally.baseline

@@ -24,7 +24,15 @@
     >:=> (line 3, col 4) to (line 3, col 13)
 4  >} catch (e) {
 
-     ~~~~~~~~~~~~~                                => Pos: (34 to 46)  SpanInfo: {"start":51,"length":9}
+     ~~~~~~~~                                     => Pos: (34 to 41)  SpanInfo: {"start":51,"length":9}
+    >x = x - 1
+    >:=> (line 5, col 4) to (line 5, col 13)
+4  >} catch (e) {
+
+             ~                                    => Pos: (42 to 42)  SpanInfo: undefined
+4  >} catch (e) {
+
+              ~~~~                                => Pos: (43 to 46)  SpanInfo: {"start":51,"length":9}
     >x = x - 1
     >:=> (line 5, col 4) to (line 5, col 13)
 --------------------------------
@@ -94,7 +102,15 @@
 --------------------------------
 14 >catch (e)
 
-    ~~~~~~~~~~                                    => Pos: (138 to 147)  SpanInfo: {"start":154,"length":9}
+    ~~~~~~~                                       => Pos: (138 to 144)  SpanInfo: {"start":154,"length":9}
+    >x = x - 1
+    >:=> (line 16, col 4) to (line 16, col 13)
+14 >catch (e)
+
+           ~                                      => Pos: (145 to 145)  SpanInfo: undefined
+14 >catch (e)
+
+            ~~                                    => Pos: (146 to 147)  SpanInfo: {"start":154,"length":9}
     >x = x - 1
     >:=> (line 16, col 4) to (line 16, col 13)
 --------------------------------

tests/baselines/reference/catchClauseWithBindingPattern1.errors.txt

@@ -0,0 +1,10 @@
+tests/cases/compiler/catchClauseWithBindingPattern1.ts(3,8): error TS1195: Catch clause variable name must be an identifier.
+
+
+==== tests/cases/compiler/catchClauseWithBindingPattern1.ts (1 errors) ====
+    try {
+    }
+    catch ({a}) {
+           ~
+!!! error TS1195: Catch clause variable name must be an identifier.
+    }

tests/baselines/reference/catchClauseWithBindingPattern1.js

@@ -0,0 +1,11 @@
+//// [catchClauseWithBindingPattern1.ts]
+try {
+}
+catch ({a}) {
+}
+
+//// [catchClauseWithBindingPattern1.js]
+try {
+}
+catch (a = (void 0).a) {
+}

tests/baselines/reference/catchClauseWithInitializer1.errors.txt

@@ -0,0 +1,10 @@
+tests/cases/compiler/catchClauseWithInitializer1.ts(3,12): error TS1197: Catch clause variable cannot have an initializer.
+
+
+==== tests/cases/compiler/catchClauseWithInitializer1.ts (1 errors) ====
+    try {
+    }
+    catch (e = 1) {
+               ~
+!!! error TS1197: Catch clause variable cannot have an initializer.
+    }

tests/baselines/reference/catchClauseWithInitializer1.js

@@ -0,0 +1,11 @@
+//// [catchClauseWithInitializer1.ts]
+try {
+}
+catch (e = 1) {
+}
+
+//// [catchClauseWithInitializer1.js]
+try {
+}
+catch (e = 1) {
+}

tests/baselines/reference/catchClauseWithTypeAnnotation.errors.txt

@@ -1,9 +1,9 @@
-tests/cases/compiler/catchClauseWithTypeAnnotation.ts(2,11): error TS1013: Catch clause parameter cannot have a type annotation.
+tests/cases/compiler/catchClauseWithTypeAnnotation.ts(2,13): error TS1196: Catch clause variable cannot have a type annotation.
 
 
 ==== tests/cases/compiler/catchClauseWithTypeAnnotation.ts (1 errors) ====
     try {
     } catch (e: any) {
-              ~
-!!! error TS1013: Catch clause parameter cannot have a type annotation.
+                ~~~
+!!! error TS1196: Catch clause variable cannot have a type annotation.
     }

tests/baselines/reference/computedPropertyNames10_ES5.js

@@ -20,6 +20,17 @@ var v = {
 var s;
 var n;
 var a;
-var v = (_a = {}, _a[s] = function () { }, _a[n] = function () { }, _a[s + s] = function () { }, _a[s + n] = function () { }, _a[+s] = function () { }, _a[""] = function () { }, _a[0] = function () { }, _a[a] = function () { }, _a[true] = function () { }, _a["hello bye"] = function () { }, _a["hello " + a + " bye"] = function () { },
+var v = (_a = {},
+    _a[s] = function () { },
+    _a[n] = function () { },
+    _a[s + s] = function () { },
+    _a[s + n] = function () { },
+    _a[+s] = function () { },
+    _a[""] = function () { },
+    _a[0] = function () { },
+    _a[a] = function () { },
+    _a[true] = function () { },
+    _a["hello bye"] = function () { },
+    _a["hello " + a + " bye"] = function () { },
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames11_ES5.js

@@ -20,6 +20,17 @@ var v = {
 var s;
 var n;
 var a;
-var v = (_a = {}, _a[s] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a[n] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }), _a[s + s] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a[s + n] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }), _a[+s] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a[""] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }), _a[0] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a[a] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }), _a[true] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a["hello bye"] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }), _a["hello " + a + " bye"] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+var v = (_a = {},
+    _a[s] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a[n] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
+    _a[s + s] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a[s + n] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
+    _a[+s] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a[""] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
+    _a[0] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a[a] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
+    _a[true] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a["hello bye"] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
+    _a["hello " + a + " bye"] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames18_ES5.js

@@ -7,8 +7,8 @@ function foo() {
 
 //// [computedPropertyNames18_ES5.js]
 function foo() {
-    var obj = (_a = {}, _a[this.bar] =
-        0,
+    var obj = (_a = {},
+        _a[this.bar] = 0,
         _a);
     var _a;
 }

tests/baselines/reference/computedPropertyNames19_ES5.js

@@ -8,8 +8,8 @@ module M {
 //// [computedPropertyNames19_ES5.js]
 var M;
 (function (M) {
-    var obj = (_a = {}, _a[this.bar] =
-        0,
+    var obj = (_a = {},
+        _a[this.bar] = 0,
         _a);
     var _a;
 })(M || (M = {}));

tests/baselines/reference/computedPropertyNames1_ES5.js

@@ -5,6 +5,8 @@ var v = {
 }
 
 //// [computedPropertyNames1_ES5.js]
-var v = (_a = {}, _a[0 + 1] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a[0 + 1] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
+var v = (_a = {},
+    _a[0 + 1] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a[0 + 1] = Object.defineProperty({ set: function (v) { }, enumerable: true, configurable: true }),
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames20_ES5.js

@@ -4,7 +4,7 @@ var obj = {
 }
 
 //// [computedPropertyNames20_ES5.js]
-var obj = (_a = {}, _a[this.bar] =
-    0,
+var obj = (_a = {},
+    _a[this.bar] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames22_ES5.js

@@ -13,7 +13,8 @@ var C = (function () {
     function C() {
     }
     C.prototype.bar = function () {
-        var obj = (_a = {}, _a[this.bar()] = function () { },
+        var obj = (_a = {},
+            _a[this.bar()] = function () { },
             _a);
         return 0;
         var _a;

tests/baselines/reference/computedPropertyNames23_ES5.js

@@ -15,8 +15,8 @@ var C = (function () {
     C.prototype.bar = function () {
         return 0;
     };
-    C.prototype[(_a = {}, _a[this.bar()] =
-        1,
+    C.prototype[(_a = {},
+        _a[this.bar()] = 1,
         _a)[0]] = function () { };
     return C;
 })();

tests/baselines/reference/computedPropertyNames25_ES5.js

@@ -34,7 +34,8 @@ var C = (function (_super) {
         _super.apply(this, arguments);
     }
     C.prototype.foo = function () {
-        var obj = (_a = {}, _a[_super.prototype.bar.call(this)] = function () { },
+        var obj = (_a = {},
+            _a[_super.prototype.bar.call(this)] = function () { },
             _a);
         return 0;
         var _a;

tests/baselines/reference/computedPropertyNames26_ES5.js

@@ -34,8 +34,8 @@ var C = (function (_super) {
     }
     // Gets emitted as super, not _super, which is consistent with
     // use of super in static properties initializers.
-    C.prototype[(_a = {}, _a[super.bar.call(this)] =
-        1,
+    C.prototype[(_a = {},
+        _a[super.bar.call(this)] = 1,
         _a)[0]] = function () { };
     return C;
 })(Base);

tests/baselines/reference/computedPropertyNames28_ES5.js

@@ -26,7 +26,8 @@ var C = (function (_super) {
     __extends(C, _super);
     function C() {
         _super.call(this);
-        var obj = (_a = {}, _a[(_super.call(this), "prop")] = function () { },
+        var obj = (_a = {},
+            _a[(_super.call(this), "prop")] = function () { },
             _a);
         var _a;
     }

tests/baselines/reference/computedPropertyNames29_ES5.js

@@ -17,7 +17,8 @@ var C = (function () {
     C.prototype.bar = function () {
         var _this = this;
         (function () {
-            var obj = (_a = {}, _a[_this.bar()] = function () { },
+            var obj = (_a = {},
+                _a[_this.bar()] = function () { },
                 _a);
             var _a;
         });

tests/baselines/reference/computedPropertyNames30_ES5.js

@@ -32,7 +32,8 @@ var C = (function (_super) {
     function C() {
         _super.call(this);
         (function () {
-            var obj = (_a = {}, _a[(_super.call(this), "prop")] = function () { },
+            var obj = (_a = {},
+                _a[(_super.call(this), "prop")] = function () { },
                 _a);
             var _a;
         });

tests/baselines/reference/computedPropertyNames31_ES5.js

@@ -38,7 +38,8 @@ var C = (function (_super) {
     C.prototype.foo = function () {
         var _this = this;
         (function () {
-            var obj = (_a = {}, _a[_super.prototype.bar.call(_this)] = function () { },
+            var obj = (_a = {},
+                _a[_super.prototype.bar.call(_this)] = function () { },
                 _a);
             var _a;
         });

tests/baselines/reference/computedPropertyNames33_ES5.js

@@ -15,7 +15,8 @@ var C = (function () {
     function C() {
     }
     C.prototype.bar = function () {
-        var obj = (_a = {}, _a[foo()] = function () { },
+        var obj = (_a = {},
+            _a[foo()] = function () { },
             _a);
         return 0;
         var _a;

tests/baselines/reference/computedPropertyNames34_ES5.js

@@ -15,7 +15,8 @@ var C = (function () {
     function C() {
     }
     C.bar = function () {
-        var obj = (_a = {}, _a[foo()] = function () { },
+        var obj = (_a = {},
+            _a[foo()] = function () { },
             _a);
         return 0;
         var _a;

tests/baselines/reference/computedPropertyNames46_ES5.js

@@ -4,7 +4,7 @@ var o = {
 };
 
 //// [computedPropertyNames46_ES5.js]
-var o = (_a = {}, _a["" || 0] =
-    0,
+var o = (_a = {},
+    _a["" || 0] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames47_ES5.js

@@ -14,7 +14,7 @@ var E2;
 (function (E2) {
     E2[E2["x"] = 0] = "x";
 })(E2 || (E2 = {}));
-var o = (_a = {}, _a[0 /* x */ || 0 /* x */] =
-    0,
+var o = (_a = {},
+    _a[0 /* x */ || 0 /* x */] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames48_ES5.js

@@ -23,13 +23,13 @@ var E;
     E[E["x"] = 0] = "x";
 })(E || (E = {}));
 var a;
-extractIndexer((_a = {}, _a[a] =
-    "",
+extractIndexer((_a = {},
+    _a[a] = "",
     _a)); // Should return string
-extractIndexer((_b = {}, _b[0 /* x */] =
-    "",
+extractIndexer((_b = {},
+    _b[0 /* x */] = "",
     _b)); // Should return string
-extractIndexer((_c = {}, _c["" || 0] =
-    "",
+extractIndexer((_c = {},
+    _c["" || 0] = "",
     _c)); // Should return any (widened form of undefined)
 var _a, _b, _c;

tests/baselines/reference/computedPropertyNames49_ES5.js

@@ -28,19 +28,23 @@ var x = {
 //// [computedPropertyNames49_ES5.js]
 var x = (_a = {
     p1: 10
-}, _a.p1 =
-    10, _a[1 + 1] = Object.defineProperty({ get: function () {
-        throw 10;
-    }, enumerable: true, configurable: true }), _a[1 + 1] = Object.defineProperty({ get: function () {
-        return 10;
-    }, enumerable: true, configurable: true }), _a[1 + 1] = Object.defineProperty({ set: function () {
-        // just throw
-        throw 10;
-    }, enumerable: true, configurable: true }), _a.foo = Object.defineProperty({ get: function () {
-        if (1 == 1) {
+},
+    _a.p1 = 10,
+    _a[1 + 1] = Object.defineProperty({ get: function () {
+            throw 10;
+        }, enumerable: true, configurable: true }),
+    _a[1 + 1] = Object.defineProperty({ get: function () {
             return 10;
-        }
-    }, enumerable: true, configurable: true }), _a.p2 =
-    20,
+        }, enumerable: true, configurable: true }),
+    _a[1 + 1] = Object.defineProperty({ set: function () {
+            // just throw
+            throw 10;
+        }, enumerable: true, configurable: true }),
+    _a.foo = Object.defineProperty({ get: function () {
+            if (1 == 1) {
+                return 10;
+            }
+        }, enumerable: true, configurable: true }),
+    _a.p2 = 20,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames4_ES5.js

@@ -20,17 +20,17 @@ var v = {
 var s;
 var n;
 var a;
-var v = (_a = {}, _a[s] =
-    0, _a[n] =
-    n, _a[s + s] =
-    1, _a[s + n] =
-    2, _a[+s] =
-    s, _a[""] =
-    0, _a[0] =
-    0, _a[a] =
-    1, _a[true] =
-    0, _a["hello bye"] =
-    0, _a["hello " + a + " bye"] =
-    0,
+var v = (_a = {},
+    _a[s] = 0,
+    _a[n] = n,
+    _a[s + s] = 1,
+    _a[s + n] = 2,
+    _a[+s] = s,
+    _a[""] = 0,
+    _a[0] = 0,
+    _a[a] = 1,
+    _a[true] = 0,
+    _a["hello bye"] = 0,
+    _a["hello " + a + " bye"] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames50_ES5.js

@@ -33,19 +33,23 @@ var x = (_a = {
             return 10;
         }
     }
-}, _a.p1 =
-    10, _a.foo = Object.defineProperty({ get: function () {
-        if (1 == 1) {
+},
+    _a.p1 = 10,
+    _a.foo = Object.defineProperty({ get: function () {
+            if (1 == 1) {
+                return 10;
+            }
+        }, enumerable: true, configurable: true }),
+    _a[1 + 1] = Object.defineProperty({ get: function () {
+            throw 10;
+        }, enumerable: true, configurable: true }),
+    _a[1 + 1] = Object.defineProperty({ set: function () {
+            // just throw
+            throw 10;
+        }, enumerable: true, configurable: true }),
+    _a[1 + 1] = Object.defineProperty({ get: function () {
             return 10;
-        }
-    }, enumerable: true, configurable: true }), _a[1 + 1] = Object.defineProperty({ get: function () {
-        throw 10;
-    }, enumerable: true, configurable: true }), _a[1 + 1] = Object.defineProperty({ set: function () {
-        // just throw
-        throw 10;
-    }, enumerable: true, configurable: true }), _a[1 + 1] = Object.defineProperty({ get: function () {
-        return 10;
-    }, enumerable: true, configurable: true }), _a.p2 =
-    20,
+        }, enumerable: true, configurable: true }),
+    _a.p2 = 20,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames5_ES5.js

@@ -11,12 +11,12 @@ var v = {
 
 //// [computedPropertyNames5_ES5.js]
 var b;
-var v = (_a = {}, _a[b] =
-    0, _a[true] =
-    1, _a[[]] =
-    0, _a[{}] =
-    0, _a[undefined] =
-    undefined, _a[null] =
-    null,
+var v = (_a = {},
+    _a[b] = 0,
+    _a[true] = 1,
+    _a[[]] = 0,
+    _a[{}] = 0,
+    _a[undefined] = undefined,
+    _a[null] = null,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames6_ES5.js

@@ -12,9 +12,9 @@ var v = {
 var p1;
 var p2;
 var p3;
-var v = (_a = {}, _a[p1] =
-    0, _a[p2] =
-    1, _a[p3] =
-    2,
+var v = (_a = {},
+    _a[p1] = 0,
+    _a[p2] = 1,
+    _a[p3] = 2,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames7_ES5.js

@@ -11,7 +11,7 @@ var E;
 (function (E) {
     E[E["member"] = 0] = "member";
 })(E || (E = {}));
-var v = (_a = {}, _a[0 /* member */] =
-    0,
+var v = (_a = {},
+    _a[0 /* member */] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNames8_ES5.js

@@ -12,9 +12,9 @@ function f<T, U extends string>() {
 function f() {
     var t;
     var u;
-    var v = (_a = {}, _a[t] =
-        0, _a[u] =
-        1,
+    var v = (_a = {},
+        _a[t] = 0,
+        _a[u] = 1,
         _a);
     var _a;
 }

tests/baselines/reference/computedPropertyNames9_ES5.js

@@ -12,9 +12,9 @@ var v = {
 
 //// [computedPropertyNames9_ES5.js]
 function f(x) { }
-var v = (_a = {}, _a[f("")] =
-    0, _a[f(0)] =
-    0, _a[f(true)] =
-    0,
+var v = (_a = {},
+    _a[f("")] = 0,
+    _a[f(0)] = 0,
+    _a[f(true)] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType10_ES5.js

@@ -9,8 +9,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType10_ES5.js]
-var o = (_a = {}, _a[+"foo"] =
-    "", _a[+"bar"] =
-    0,
+var o = (_a = {},
+    _a[+"foo"] = "",
+    _a[+"bar"] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType1_ES5.js

@@ -10,7 +10,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType1_ES5.js]
-var o = (_a = {}, _a["" + 0] = function (y) { return y.length; }, _a["" + 1] =
-    function (y) { return y.length; },
+var o = (_a = {},
+    _a["" + 0] = function (y) { return y.length; },
+    _a["" + 1] = function (y) { return y.length; },
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType2_ES5.js

@@ -10,7 +10,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType2_ES5.js]
-var o = (_a = {}, _a[+"foo"] = function (y) { return y.length; }, _a[+"bar"] =
-    function (y) { return y.length; },
+var o = (_a = {},
+    _a[+"foo"] = function (y) { return y.length; },
+    _a[+"bar"] = function (y) { return y.length; },
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType3_ES5.js

@@ -9,7 +9,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType3_ES5.js]
-var o = (_a = {}, _a[+"foo"] = function (y) { return y.length; }, _a[+"bar"] =
-    function (y) { return y.length; },
+var o = (_a = {},
+    _a[+"foo"] = function (y) { return y.length; },
+    _a[+"bar"] = function (y) { return y.length; },
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType4_ES5.js

@@ -10,8 +10,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType4_ES5.js]
-var o = (_a = {}, _a["" + "foo"] =
-    "", _a["" + "bar"] =
-    0,
+var o = (_a = {},
+    _a["" + "foo"] = "",
+    _a["" + "bar"] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType5_ES5.js

@@ -10,8 +10,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType5_ES5.js]
-var o = (_a = {}, _a[+"foo"] =
-    "", _a[+"bar"] =
-    0,
+var o = (_a = {},
+    _a[+"foo"] = "",
+    _a[+"bar"] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType6_ES5.js

@@ -17,11 +17,11 @@ foo({
 foo((_a = {
     p: "",
     0: function () { }
-}, _a.p =
-    "", _a[0] =
-    function () { }, _a["hi" + "bye"] =
-    true, _a[0 + 1] =
-    0, _a[+"hi"] =
-    [0],
+},
+    _a.p = "",
+    _a[0] = function () { },
+    _a["hi" + "bye"] = true,
+    _a[0 + 1] = 0,
+    _a[+"hi"] = [0],
     _a));
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType7_ES5.js

@@ -17,11 +17,11 @@ foo({
 foo((_a = {
     p: "",
     0: function () { }
-}, _a.p =
-    "", _a[0] =
-    function () { }, _a["hi" + "bye"] =
-    true, _a[0 + 1] =
-    0, _a[+"hi"] =
-    [0],
+},
+    _a.p = "",
+    _a[0] = function () { },
+    _a["hi" + "bye"] = true,
+    _a[0 + 1] = 0,
+    _a[+"hi"] = [0],
     _a));
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType8_ES5.js

@@ -10,8 +10,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType8_ES5.js]
-var o = (_a = {}, _a["" + "foo"] =
-    "", _a["" + "bar"] =
-    0,
+var o = (_a = {},
+    _a["" + "foo"] = "",
+    _a["" + "bar"] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesContextualType9_ES5.js

@@ -10,8 +10,8 @@ var o: I = {
 }
 
 //// [computedPropertyNamesContextualType9_ES5.js]
-var o = (_a = {}, _a[+"foo"] =
-    "", _a[+"bar"] =
-    0,
+var o = (_a = {},
+    _a[+"foo"] = "",
+    _a[+"bar"] = 0,
     _a);
 var _a;

tests/baselines/reference/computedPropertyNamesDeclarationEmit5_ES5.js

@@ -7,8 +7,11 @@ var v = {
 }
 
 //// [computedPropertyNamesDeclarationEmit5_ES5.js]
-var v = (_a = {}, _a["" + ""] =
-    0, _a["" + ""] = function () { }, _a["" + ""] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }), _a["" + ""] = Object.defineProperty({ set: function (x) { }, enumerable: true, configurable: true }),
+var v = (_a = {},
+    _a["" + ""] = 0,
+    _a["" + ""] = function () { },
+    _a["" + ""] = Object.defineProperty({ get: function () { return 0; }, enumerable: true, configurable: true }),
+    _a["" + ""] = Object.defineProperty({ set: function (x) { }, enumerable: true, configurable: true }),
     _a);
 var _a;
 

tests/baselines/reference/computedPropertyNamesSourceMap2_ES5.js

@@ -6,9 +6,10 @@ var v = {
 }
 
 //// [computedPropertyNamesSourceMap2_ES5.js]
-var v = (_a = {}, _a["hello"] = function () {
-    debugger;
-},
+var v = (_a = {},
+    _a["hello"] = function () {
+        debugger;
+    },
     _a);
 var _a;
 //# sourceMappingURL=computedPropertyNamesSourceMap2_ES5.js.map

tests/baselines/reference/computedPropertyNamesSourceMap2_ES5.js.map

@@ -1,2 +1,2 @@
 //// [computedPropertyNamesSourceMap2_ES5.js.map]
-{"version":3,"file":"computedPropertyNamesSourceMap2_ES5.js","sourceRoot":"","sources":["computedPropertyNamesSourceMap2_ES5.ts"],"names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,AADA,CACA,EAAA,GADA,EAAA,EACA,EAAA,CACK,OAAO,CAFA,GAAA;IAGA,QAAQ,CAAC;AACb,CAAC,AAJA;IACA,EAAA,AADA,CAKA,CAAA;IAJD,EAAA"}
+{"version":3,"file":"computedPropertyNamesSourceMap2_ES5.js","sourceRoot":"","sources":["computedPropertyNamesSourceMap2_ES5.ts"],"names":[],"mappings":"AAAA,IAAI,CAAC,GAAG,AADA,CAAA,EAAA,GAAA,EAAA;IAAA,EAAA,CAEA,OAAO,CAFA,GAAA;QAGA,QAAQ,CAAC;IACb,CAAC,AAJA;IAAA,EAAA,CAKA,CAAA;IALA,EAAA"}

tests/baselines/reference/computedPropertyNamesSourceMap2_ES5.sourcemap.txt

@@ -8,7 +8,7 @@ sources: computedPropertyNamesSourceMap2_ES5.ts
 emittedFile:tests/cases/conformance/es6/computedProperties/computedPropertyNamesSourceMap2_ES5.js
 sourceFile:computedPropertyNamesSourceMap2_ES5.ts
 -------------------------------------------------------------------
->>>var v = (_a = {}, _a["hello"] = function () {
+>>>var v = (_a = {},
 1 >
 2 >^^^^
 3 >    ^
@@ -18,12 +18,7 @@ sourceFile:computedPropertyNamesSourceMap2_ES5.ts
 7 >         ^^
 8 >           ^^^
 9 >              ^^
-10>                ^^
-11>                  ^^
-12>                    ^
-13>                     ^^^^^^^
-14>                            ^
-15>                             ^^^
+10>                ^^^^^^^^^^^^^^^^->
 1 >
 2 >var 
 3 >    v
@@ -32,128 +27,130 @@ sourceFile:computedPropertyNamesSourceMap2_ES5.ts
 5 >        !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 9) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 9) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 5 >        
 6 >        !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
-6 >        !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 9) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 10) Source(1, 1) + SourceIndex(0) nameIndex (-1)
+6 >        !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 9) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 10) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 6 >        
-7 >         !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-7 >         !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 10) Source(1, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 12) Source(1, 1) + SourceIndex(0) nameIndex (-1)
+7 >         !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
+7 >         !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 10) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 12) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 7 >         
-8 >           !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-8 >           !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 12) Source(1, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 15) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+8 >           !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+8 >           !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 10) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 15) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 8 >           
 9 >              !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
-9 >              !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 15) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 17) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+9 >              !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 12) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 17) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 9 >              
-10>                !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
-10>                !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 15) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 19) Source(1, 1) + SourceIndex(0) nameIndex (-1)
-10>                
-11>                  !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
-11>                  !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 17) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 21) Source(1, 1) + SourceIndex(0) nameIndex (-1)
-11>                  
-12>                    !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
-12>                    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 17) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 22) Source(2, 6) + SourceIndex(0) nameIndex (-1)
-12>                    var v = {
-  >                        [
-13>                     !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-13>                     !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 19) Source(1, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 29) Source(2, 13) + SourceIndex(0) nameIndex (-1)
-13>                     "hello"
-14>                            !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-14>                            !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 21) Source(1, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 30) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
-14>                            
-15>                             !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-15>                             !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 22) Source(2, 14) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(1, 33) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
-15>                             
 1 >Emitted(1, 1) Source(1, 1) + SourceIndex(0)
 2 >Emitted(1, 5) Source(1, 5) + SourceIndex(0)
 3 >Emitted(1, 6) Source(1, 6) + SourceIndex(0)
 4 >Emitted(1, 9) Source(1, 9) + SourceIndex(0)
 5 >Emitted(1, 9) Source(0, NaN) + SourceIndex(0)
-6 >Emitted(1, 10) Source(1, 1) + SourceIndex(0)
-7 >Emitted(1, 12) Source(1, 1) + SourceIndex(0)
+6 >Emitted(1, 10) Source(0, NaN) + SourceIndex(0)
+7 >Emitted(1, 12) Source(0, NaN) + SourceIndex(0)
 8 >Emitted(1, 15) Source(0, NaN) + SourceIndex(0)
 9 >Emitted(1, 17) Source(0, NaN) + SourceIndex(0)
-10>Emitted(1, 19) Source(1, 1) + SourceIndex(0)
-11>Emitted(1, 21) Source(1, 1) + SourceIndex(0)
-12>Emitted(1, 22) Source(2, 6) + SourceIndex(0)
-13>Emitted(1, 29) Source(2, 13) + SourceIndex(0)
-14>Emitted(1, 30) Source(0, NaN) + SourceIndex(0)
-15>Emitted(1, 33) Source(0, NaN) + SourceIndex(0)
 ---
->>>    debugger;
-1 >^^^^
-2 >    ^^^^^^^^
-3 >            ^
-1 >!!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-1 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 29) Source(2, 21) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 5) Source(3, 9) + SourceIndex(0) nameIndex (-1)
-1 >
+>>>    _a["hello"] = function () {
+1->^^^^
+2 >    ^^
+3 >      ^
+4 >       ^^^^^^^
+5 >              ^
+6 >               ^^^
+1->!!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+1->!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 12) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 5) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+1->
 2 >    !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
-2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 30) Source(0, 21) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 13) Source(3, 17) + SourceIndex(0) nameIndex (-1)
-2 >    debugger
-3 >            !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
-3 >            !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 30) Source(0, 21) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 14) Source(3, 18) + SourceIndex(0) nameIndex (-1)
-3 >            ;
-1 >Emitted(2, 5) Source(3, 9) + SourceIndex(0)
-2 >Emitted(2, 13) Source(3, 17) + SourceIndex(0)
-3 >Emitted(2, 14) Source(3, 18) + SourceIndex(0)
+2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 15) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 7) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+2 >    
+3 >      !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+3 >      !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 15) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 8) Source(2, 6) + SourceIndex(0) nameIndex (-1)
+3 >      
+4 >       !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
+4 >       !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 17) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 15) Source(2, 13) + SourceIndex(0) nameIndex (-1)
+4 >       "hello"
+5 >              !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+5 >              !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 17) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 16) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+5 >              
+6 >               !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
+6 >               !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 5) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(2, 19) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+6 >               
+1->Emitted(2, 5) Source(0, NaN) + SourceIndex(0)
+2 >Emitted(2, 7) Source(0, NaN) + SourceIndex(0)
+3 >Emitted(2, 8) Source(2, 6) + SourceIndex(0)
+4 >Emitted(2, 15) Source(2, 13) + SourceIndex(0)
+5 >Emitted(2, 16) Source(0, NaN) + SourceIndex(0)
+6 >Emitted(2, 19) Source(0, NaN) + SourceIndex(0)
 ---
->>>},
+>>>        debugger;
+1 >^^^^^^^^
+2 >        ^^^^^^^^
+3 >                ^
+1 >!!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+1 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 5) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(3, 9) Source(3, 9) + SourceIndex(0) nameIndex (-1)
 1 >
-2 >^
-3 > 
-4 > ^^^^^^^^->
-1 >!!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
-1 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 33) Source(0, 21) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(3, 1) Source(4, 5) + SourceIndex(0) nameIndex (-1)
+2 >        !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
+2 >        !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 7) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(3, 17) Source(3, 17) + SourceIndex(0) nameIndex (-1)
+2 >        debugger
+3 >                !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+3 >                !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 7) Source(0, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(3, 18) Source(3, 18) + SourceIndex(0) nameIndex (-1)
+3 >                ;
+1 >Emitted(3, 9) Source(3, 9) + SourceIndex(0)
+2 >Emitted(3, 17) Source(3, 17) + SourceIndex(0)
+3 >Emitted(3, 18) Source(3, 18) + SourceIndex(0)
+---
+>>>    },
+1 >^^^^
+2 >    ^
+3 >     
+4 >     ^^^^->
+1 >!!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
+1 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 8) Source(2, 9) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 5) Source(4, 5) + SourceIndex(0) nameIndex (-1)
 1 >
   >    
-2 >!!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
-2 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(1, 33) Source(0, 21) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(3, 2) Source(4, 6) + SourceIndex(0) nameIndex (-1)
-2 >}
-3 > !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-3 > !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 5) Source(3, 21) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(3, 2) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
-3 > 
-1 >Emitted(3, 1) Source(4, 5) + SourceIndex(0)
-2 >Emitted(3, 2) Source(4, 6) + SourceIndex(0)
-3 >Emitted(3, 2) Source(0, NaN) + SourceIndex(0)
+2 >    !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
+2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 15) Source(2, 16) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 6) Source(4, 6) + SourceIndex(0) nameIndex (-1)
+2 >    }
+3 >     !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
+3 >     !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 16) Source(0, 16) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 6) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+3 >     
+1 >Emitted(4, 5) Source(4, 5) + SourceIndex(0)
+2 >Emitted(4, 6) Source(4, 6) + SourceIndex(0)
+3 >Emitted(4, 6) Source(0, NaN) + SourceIndex(0)
 ---
 >>>    _a);
 1->^^^^
 2 >    ^^
-3 >      
-4 >      ^
-5 >       ^
-1->!!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-1->!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 13) Source(3, 29) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 5) Source(1, 1) + SourceIndex(0) nameIndex (-1)
+3 >      ^
+4 >       ^
+1->!!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+1->!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 16) Source(0, 16) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(5, 5) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 1->
-2 >    !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 14) Source(3, 30) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 7) Source(1, 1) + SourceIndex(0) nameIndex (-1)
+2 >    !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
+2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 19) Source(0, 16) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(5, 7) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 2 >    
-3 >      !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-3 >      !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 1) Source(4, 17) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 7) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
+3 >      !!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
+3 >      !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(2, 19) Source(0, 16) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(5, 8) Source(5, 2) + SourceIndex(0) nameIndex (-1)
 3 >      
-4 >      !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-4 >      !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 2) Source(4, 18) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 8) Source(5, 2) + SourceIndex(0) nameIndex (-1)
-4 >      
-5 >       !!^^ !!^^ There was decoding error in the sourcemap at this location: Invalid sourceLine found
-5 >       !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 2) Source(0, 18) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(4, 9) Source(5, 2) + SourceIndex(0) nameIndex (-1)
-5 >       
-1->Emitted(4, 5) Source(1, 1) + SourceIndex(0)
-2 >Emitted(4, 7) Source(1, 1) + SourceIndex(0)
-3 >Emitted(4, 7) Source(0, NaN) + SourceIndex(0)
-4 >Emitted(4, 8) Source(5, 2) + SourceIndex(0)
-5 >Emitted(4, 9) Source(5, 2) + SourceIndex(0)
+4 >       !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
+4 >       !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 9) Source(3, 16) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(5, 9) Source(5, 2) + SourceIndex(0) nameIndex (-1)
+4 >       
+1->Emitted(5, 5) Source(0, NaN) + SourceIndex(0)
+2 >Emitted(5, 7) Source(0, NaN) + SourceIndex(0)
+3 >Emitted(5, 8) Source(5, 2) + SourceIndex(0)
+4 >Emitted(5, 9) Source(5, 2) + SourceIndex(0)
 ---
 >>>var _a;
 1 >^^^^
 2 >    ^^
 3 >      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^->
-1 >!!^^ !!^^ There was decoding error in the sourcemap at this location: Unsupported Error Format: No entries after emitted column
-1 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 2) Source(0, 18) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(5, 5) Source(1, 1) + SourceIndex(0) nameIndex (-1)
+1 >!!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
+1 >!!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 17) Source(3, 24) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(6, 5) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 1 >
 2 >    !!^^ !!^^ The decoded span from sourcemap's mapping entry does not match what was encoded for this span:
-2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(4, 5) Source(1, 18) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(5, 7) Source(1, 1) + SourceIndex(0) nameIndex (-1)
+2 >    !!^^ !!^^ Decoded span from sourcemap's mappings entry: Emitted(3, 18) Source(3, 25) + SourceIndex(0) nameIndex (-1) Span encoded by the emitter:Emitted(6, 7) Source(0, NaN) + SourceIndex(0) nameIndex (-1)
 2 >    
-1 >Emitted(5, 5) Source(1, 1) + SourceIndex(0)
-2 >Emitted(5, 7) Source(1, 1) + SourceIndex(0)
+1 >Emitted(6, 5) Source(0, NaN) + SourceIndex(0)
+2 >Emitted(6, 7) Source(0, NaN) + SourceIndex(0)
 ---
 !!!! **** There are more source map entries in the sourceMap's mapping than what was encoded
-!!!! **** Remaining decoded string: ,EAAA,AADA,CAKA,CAAA;IAJD,EAAA
+!!!! **** Remaining decoded string: ;IACb,CAAC,AAJA;IAAA,EAAA,CAKA,CAAA;IALA,EAAA
 >>>//# sourceMappingURL=computedPropertyNamesSourceMap2_ES5.js.map

tests/baselines/reference/constDeclarations-errors.errors.txt

@@ -4,13 +4,12 @@ tests/cases/compiler/constDeclarations-errors.ts(5,7): error TS1155: 'const' dec
 tests/cases/compiler/constDeclarations-errors.ts(5,11): error TS1155: 'const' declarations must be initialized
 tests/cases/compiler/constDeclarations-errors.ts(5,15): error TS1155: 'const' declarations must be initialized
 tests/cases/compiler/constDeclarations-errors.ts(5,27): error TS1155: 'const' declarations must be initialized
-tests/cases/compiler/constDeclarations-errors.ts(8,11): error TS1155: 'const' declarations must be initialized
-tests/cases/compiler/constDeclarations-errors.ts(11,27): error TS2449: The operand of an increment or decrement operator cannot be a constant.
-tests/cases/compiler/constDeclarations-errors.ts(14,11): error TS1155: 'const' declarations must be initialized
-tests/cases/compiler/constDeclarations-errors.ts(17,20): error TS1155: 'const' declarations must be initialized
+tests/cases/compiler/constDeclarations-errors.ts(10,27): error TS2449: The operand of an increment or decrement operator cannot be a constant.
+tests/cases/compiler/constDeclarations-errors.ts(13,11): error TS1155: 'const' declarations must be initialized
+tests/cases/compiler/constDeclarations-errors.ts(16,20): error TS1155: 'const' declarations must be initialized
 
 
-==== tests/cases/compiler/constDeclarations-errors.ts (10 errors) ====
+==== tests/cases/compiler/constDeclarations-errors.ts (9 errors) ====
     
     // error, missing intialicer
     const c1;
@@ -29,10 +28,7 @@ tests/cases/compiler/constDeclarations-errors.ts(17,20): error TS1155: 'const' d
                               ~~
 !!! error TS1155: 'const' declarations must be initialized
     
-    // error, can not be unintalized
     for(const c in {}) { }
-              ~
-!!! error TS1155: 'const' declarations must be initialized
     
     // error, assigning to a const
     for(const c8 = 0; c8 < 1; c8++) { }

tests/baselines/reference/constDeclarations-errors.js

@@ -5,7 +5,6 @@ const c1;
 const c2: number;
 const c3, c4, c5 :string, c6;  // error, missing initialicer
 
-// error, can not be unintalized
 for(const c in {}) { }
 
 // error, assigning to a const
@@ -22,8 +21,7 @@ for(const c10 = 0, c11; c10 < 1;) { }
 const c1;
 const c2;
 const c3, c4, c5, c6; // error, missing initialicer
-// error, can not be unintalized
-for (var c in {}) { }
+for (const c in {}) { }
 // error, assigning to a const
 for (const c8 = 0; c8 < 1; c8++) { }
 // error, can not be unintalized

tests/baselines/reference/constDeclarations-es5.errors.txt

@@ -1,17 +0,0 @@
-tests/cases/compiler/constDeclarations-es5.ts(2,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-tests/cases/compiler/constDeclarations-es5.ts(3,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-tests/cases/compiler/constDeclarations-es5.ts(4,1): error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-
-
-==== tests/cases/compiler/constDeclarations-es5.ts (3 errors) ====
-    
-    const z7 = false;
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-    const z8: number = 23;
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-    const z9 = 0, z10 :string = "", z11 = null;
-    ~~~~~
-!!! error TS1154: 'const' declarations are only available when targeting ECMAScript 6 and higher.
-    

tests/baselines/reference/constDeclarations-es5.js

@@ -6,6 +6,6 @@ const z9 = 0, z10 :string = "", z11 = null;
 
 
 //// [constDeclarations-es5.js]
-const z7 = false;
-const z8 = 23;
-const z9 = 0, z10 = "", z11 = null;
+var z7 = false;
+var z8 = 23;
+var z9 = 0, z10 = "", z11 = null;

tests/baselines/reference/constDeclarations-es5.types

@@ -0,0 +1,13 @@
+=== tests/cases/compiler/constDeclarations-es5.ts ===
+
+const z7 = false;
+>z7 : boolean
+
+const z8: number = 23;
+>z8 : number
+
+const z9 = 0, z10 :string = "", z11 = null;
+>z9 : number
+>z10 : string
+>z11 : any
+

tests/baselines/reference/downlevelLetConst1.errors.txt

@@ -0,0 +1,7 @@
+tests/cases/compiler/downlevelLetConst1.ts(1,6): error TS1123: Variable declaration list cannot be empty.
+
+
+==== tests/cases/compiler/downlevelLetConst1.ts (1 errors) ====
+    const
+         
+!!! error TS1123: Variable declaration list cannot be empty.

tests/baselines/reference/downlevelLetConst1.js

@@ -0,0 +1,5 @@
+//// [downlevelLetConst1.ts]
+const
+
+//// [downlevelLetConst1.js]
+var ;

tests/baselines/reference/downlevelLetConst10.js

@@ -0,0 +1,5 @@
+//// [downlevelLetConst10.ts]
+let a: number = 1
+
+//// [downlevelLetConst10.js]
+var a = 1;

tests/baselines/reference/downlevelLetConst10.types

@@ -0,0 +1,4 @@
+=== tests/cases/compiler/downlevelLetConst10.ts ===
+let a: number = 1
+>a : number
+

tests/baselines/reference/downlevelLetConst11.errors.txt

@@ -0,0 +1,8 @@
+tests/cases/compiler/downlevelLetConst11.ts(2,4): error TS1123: Variable declaration list cannot be empty.
+
+
+==== tests/cases/compiler/downlevelLetConst11.ts (1 errors) ====
+    "use strict";
+    let
+       
+!!! error TS1123: Variable declaration list cannot be empty.