From e185ebb8d52bac8e0a344629d7cfda8e7e39c2b3 Mon Sep 17 00:00:00 2001
From: Arthur Ozga <aozgaa@umich.edu>
Date: Tue, 14 Mar 2017 18:24:00 -0700
Subject: [PATCH] simplify rest param handling

---
 src/compiler/checker.ts                       |  6 ++---
 src/services/codefixes/fixAddMissingMember.ts |  4 +--
 src/services/codefixes/helpers.ts             | 25 +++++++++++--------
 3 files changed, 19 insertions(+), 16 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index e9cea047ea..df4bfbb845 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -2340,8 +2340,8 @@ namespace ts {
                     // The type is an object literal type.
                     if (!type.symbol) {
                         // Anonymous types without symbols are literals.
-                        // mapToTypeDeclarationsArray(type)
-                        throw new Error("unknown case.");
+                        // TODO: handle this case correctly.
+                        noop();
                     }
 
                     return createTypeLiteralNodeFromType(<ObjectType>type);
@@ -2471,7 +2471,7 @@ namespace ts {
                             case SyntaxKind.IndexSignature:
                                 throw new Error("type literal constituent not implemented.");
                             default:
-                                throw new Error("Unknown case.");
+                                throw new Error("Unknown resolved member kind.");
                         }
                     });
                     return typeElements.length ? typeElements : undefined;
diff --git a/src/services/codefixes/fixAddMissingMember.ts b/src/services/codefixes/fixAddMissingMember.ts
index 61c823908d..ace11cda80 100644
--- a/src/services/codefixes/fixAddMissingMember.ts
+++ b/src/services/codefixes/fixAddMissingMember.ts
@@ -52,7 +52,7 @@ namespace ts.codefix {
             , /*initializer*/ undefined);
         // TODO: make index signature.
         const propertyChangeTracker = textChanges.ChangeTracker.fromCodeFixContext(context);
-        propertyChangeTracker.insertNodeAfter(sourceFile, openBrace, property, { insertTrailingNewLine: true });
+        propertyChangeTracker.insertNodeAfter(sourceFile, openBrace, property, { suffix: context.newLineCharacter });
 
         const stringTypeNode = createKeywordTypeNode(SyntaxKind.StringKeyword);
         const indexingParameter = createParameter(
@@ -70,7 +70,7 @@ namespace ts.codefix {
             , /*modifiers*/ undefined);
 
         const indexSignatureChangeTracker = textChanges.ChangeTracker.fromCodeFixContext(context);
-        indexSignatureChangeTracker.insertNodeAfter(sourceFile, openBrace, indexSignature, { insertTrailingNewLine: true });
+        indexSignatureChangeTracker.insertNodeAfter(sourceFile, openBrace, indexSignature, { suffix: context.newLineCharacter });
 
         return [{
             description: formatStringFromArgs(getLocaleSpecificMessage(Diagnostics.Add_declaration_for_missing_property_0), [token.getText()]),
diff --git a/src/services/codefixes/helpers.ts b/src/services/codefixes/helpers.ts
index e6f4524c71..da579cccb1 100644
--- a/src/services/codefixes/helpers.ts
+++ b/src/services/codefixes/helpers.ts
@@ -11,7 +11,7 @@ namespace ts.codefix {
         const changeTracker = textChanges.ChangeTracker.fromCodeFixContext(context);
 
         for (const newNode of newNodes) {
-            changeTracker.insertNodeAfter(sourceFile, insertAfter, newNode, { insertTrailingNewLine: true });
+            changeTracker.insertNodeAfter(sourceFile, insertAfter, newNode, { suffix: context.newLineCharacter });
         }
         return changeTracker.getChanges();
     }
@@ -137,20 +137,23 @@ namespace ts.codefix {
     function createMethodImplementingSignatures(signatures: Signature[], name: PropertyName, modifiers: Modifier[] | undefined): MethodDeclaration {
         Debug.assert(signatures && signatures.length > 0);
 
-        let maxNonRestArgs = -1;
         let maxArgsIndex = 0;
+        /** This is *a* signature with the maximal number of arguments,
+         * such that if there is a "maximal" signature without rest arguments,
+         * this is one of them.
+        */
+        let maxArgsSignature = signatures[0];
         let minArgumentCount = signatures[0].minArgumentCount;
-        let hasRestParameter = false;
+        let someSigHasRestParameter = false;
         for (let i = 0; i < signatures.length; i++) {
             const sig = signatures[i];
             minArgumentCount = Math.min(sig.minArgumentCount, minArgumentCount);
-            hasRestParameter = hasRestParameter || sig.hasRestParameter;
-            const nonRestLength = sig.parameters.length - (sig.hasRestParameter ? 1 : 0);
-            if (nonRestLength >= maxNonRestArgs) {
-                maxNonRestArgs = nonRestLength;
-                maxArgsIndex = i;
+            someSigHasRestParameter = someSigHasRestParameter || sig.hasRestParameter;
+            if (sig.parameters.length >= maxArgsSignature.parameters.length && (!sig.hasRestParameter || maxArgsSignature.hasRestParameter)) {
+                maxArgsSignature = sig;
             }
         }
+        const maxNonRestArgs =  maxArgsSignature.parameters.length - (maxArgsSignature.hasRestParameter ? 1 : 0);
         const maxArgsParameterSymbolNames = signatures[maxArgsIndex].getParameters().map(symbol => symbol.getName());
 
         const parameters: ParameterDeclaration[] = [];
@@ -167,15 +170,15 @@ namespace ts.codefix {
             parameters.push(newParameter);
         }
 
-        if (hasRestParameter) {
-            const anyType = createKeywordTypeNode(SyntaxKind.AnyKeyword);
+        if (someSigHasRestParameter) {
+            const anyArrayType = createArrayTypeNode(createKeywordTypeNode(SyntaxKind.AnyKeyword));
             const restParameter = createParameter(
                   /*decorators*/ undefined
                 , /*modifiers*/ undefined
                 , createToken(SyntaxKind.DotDotDotToken)
                 , maxArgsParameterSymbolNames[maxNonRestArgs] || "rest"
                 , /*questionToken*/ maxNonRestArgs >= minArgumentCount ? createToken(SyntaxKind.QuestionToken) : undefined
-                , anyType
+                , anyArrayType
                 , /*initializer*/ undefined);
             parameters.push(restParameter);
         }