Merge pull request #5983 from SaschaNaz/formatWhitespaces

Trim empty line whitespaces

src/services/formatting/formatting.ts

@@ -121,7 +121,7 @@ namespace ts.formatting {
 
     function findOutermostParent(position: number, expectedTokenKind: SyntaxKind, sourceFile: SourceFile): Node {
         let precedingToken = findPrecedingToken(position, sourceFile);
-        
+
         // when it is claimed that trigger character was typed at given position 
         // we verify that there is a token with a matching kind whose end is equal to position (because the character was just typed).
         // If this condition is not hold - then trigger character was typed in some other context, 
@@ -151,7 +151,7 @@ namespace ts.formatting {
 
         return current;
     }
-    
+
     // Returns true if node is a element in some list in parent
     // i.e. parent is class declaration with the list of members and node is one of members.
     function isListElement(parent: Node, node: Node): boolean {
@@ -198,7 +198,7 @@ namespace ts.formatting {
         if (!errors.length) {
             return rangeHasNoErrors;
         }
-        
+
         // pick only errors that fall in range
         let sorted = errors
             .filter(d => rangeOverlapsWithStartEnd(originalRange, d.start, d.start + d.length))
@@ -341,6 +341,14 @@ namespace ts.formatting {
             processNode(enclosingNode, enclosingNode, startLine, undecoratedStartLine, initialIndentation, delta);
         }
 
+        if (!formattingScanner.isOnToken()) {
+            let leadingTrivia = formattingScanner.getCurrentLeadingTrivia();
+            if (leadingTrivia) {
+                processTrivia(leadingTrivia, enclosingNode, enclosingNode, undefined);
+                trimTrailingWhitespacesForRemainingRange();
+            }
+        }
+
         formattingScanner.close();
 
         return edits;
@@ -828,9 +836,7 @@ namespace ts.formatting {
                 }
 
                 // We need to trim trailing whitespace between the tokens if they were on different lines, and no rule was applied to put them on the same line
-                trimTrailingWhitespaces =
-                (rule.Operation.Action & (RuleAction.NewLine | RuleAction.Space)) &&
-                rule.Flag !== RuleFlags.CanDeleteNewLines;
+                trimTrailingWhitespaces = !(rule.Operation.Action & RuleAction.Delete) && rule.Flag !== RuleFlags.CanDeleteNewLines;
             }
             else {
                 trimTrailingWhitespaces = true;
@@ -929,17 +935,41 @@ namespace ts.formatting {
                     continue;
                 }
 
-                let pos = lineEndPosition;
-                while (pos >= lineStartPosition && isWhiteSpace(sourceFile.text.charCodeAt(pos))) {
-                    pos--;
-                }
-                if (pos !== lineEndPosition) {
-                    Debug.assert(pos === lineStartPosition || !isWhiteSpace(sourceFile.text.charCodeAt(pos)));
-                    recordDelete(pos + 1, lineEndPosition - pos);
+                let whitespaceStart = getTrailingWhitespaceStartPosition(lineStartPosition, lineEndPosition);
+                if (whitespaceStart !== -1) {
+                    Debug.assert(whitespaceStart === lineStartPosition || !isWhiteSpace(sourceFile.text.charCodeAt(whitespaceStart - 1)));
+                    recordDelete(whitespaceStart, lineEndPosition + 1 - whitespaceStart);
                 }
             }
         }
 
+        /**
+         * @param start The position of the first character in range
+         * @param end The position of the last character in range
+         */
+        function getTrailingWhitespaceStartPosition(start: number, end: number) {
+            let pos = end;
+            while (pos >= start && isWhiteSpace(sourceFile.text.charCodeAt(pos))) {
+                pos--;
+            }
+            if (pos !== end) {
+                return pos + 1;
+            }
+            return -1;
+        }
+
+        /**
+         * Trimming will be done for lines after the previous range
+         */
+        function trimTrailingWhitespacesForRemainingRange() {
+            let startPosition = previousRange ? previousRange.end : originalRange.pos;
+
+            let startLine = sourceFile.getLineAndCharacterOfPosition(startPosition).line;
+            let endLine = sourceFile.getLineAndCharacterOfPosition(originalRange.end).line;
+
+            trimTrailingWhitespacesForLines(startLine, endLine + 1, previousRange);
+        }
+
         function newTextChange(start: number, len: number, newText: string): TextChange {
             return { span: createTextSpan(start, len), newText }
         }

src/services/formatting/formattingScanner.ts

@@ -5,21 +5,22 @@
 namespace ts.formatting {
     const standardScanner = createScanner(ScriptTarget.Latest, /*skipTrivia*/ false, LanguageVariant.Standard);
     const jsxScanner = createScanner(ScriptTarget.Latest, /*skipTrivia*/ false, LanguageVariant.JSX);
-    
+
     /**
      * Scanner that is currently used for formatting
      */
     let scanner: Scanner;
-    
+
     export interface FormattingScanner {
         advance(): void;
         isOnToken(): boolean;
         readTokenInfo(n: Node): TokenInfo;
+        getCurrentLeadingTrivia(): TextRangeWithKind[];
         lastTrailingTriviaWasNewLine(): boolean;
         close(): void;
     }
 
-    const enum ScanAction{
+    const enum ScanAction {
         Scan,
         RescanGreaterThanToken,
         RescanSlashToken,
@@ -37,19 +38,20 @@ namespace ts.formatting {
         let wasNewLine: boolean = true;
         let leadingTrivia: TextRangeWithKind[];
         let trailingTrivia: TextRangeWithKind[];
-        
+
         let savedPos: number;
         let lastScanAction: ScanAction;
         let lastTokenInfo: TokenInfo;
 
         return {
-            advance: advance,
-            readTokenInfo: readTokenInfo,
-            isOnToken: isOnToken,
+            advance,
+            readTokenInfo,
+            isOnToken,
+            getCurrentLeadingTrivia: () => leadingTrivia,
             lastTrailingTriviaWasNewLine: () => wasNewLine,
             close: () => {
                 Debug.assert(scanner !== undefined);
-                
+
                 lastTokenInfo = undefined;
                 scanner.setText(undefined);
                 scanner = undefined;
@@ -58,7 +60,7 @@ namespace ts.formatting {
 
         function advance(): void {
             Debug.assert(scanner !== undefined);
-            
+
             lastTokenInfo = undefined;
             let isStarted = scanner.getStartPos() !== startPos;
 
@@ -81,7 +83,7 @@ namespace ts.formatting {
 
             let t: SyntaxKind;
             let pos = scanner.getStartPos();
-            
+
             // Read leading trivia and token
             while (pos < endPos) {
                 let t = scanner.getToken();
@@ -122,10 +124,10 @@ namespace ts.formatting {
 
             return false;
         }
-        
+
         function shouldRescanJsxIdentifier(node: Node): boolean {
             if (node.parent) {
-                switch(node.parent.kind) {
+                switch (node.parent.kind) {
                     case SyntaxKind.JsxAttribute:
                     case SyntaxKind.JsxOpeningElement:
                     case SyntaxKind.JsxClosingElement:
@@ -133,7 +135,7 @@ namespace ts.formatting {
                         return node.kind === SyntaxKind.Identifier;
                 }
             }
-            
+
             return false;
         }
 
@@ -142,7 +144,7 @@ namespace ts.formatting {
         }
 
         function shouldRescanTemplateToken(container: Node): boolean {
-            return container.kind === SyntaxKind.TemplateMiddle || 
+            return container.kind === SyntaxKind.TemplateMiddle ||
                 container.kind === SyntaxKind.TemplateTail;
         }
 
@@ -152,11 +154,11 @@ namespace ts.formatting {
 
         function readTokenInfo(n: Node): TokenInfo {
             Debug.assert(scanner !== undefined);
-            
+
             if (!isOnToken()) {
                 // scanner is not on the token (either advance was not called yet or scanner is already past the end position)
                 return {
-                    leadingTrivia: leadingTrivia,
+                    leadingTrivia,
                     trailingTrivia: undefined,
                     token: undefined
                 };
@@ -164,7 +166,7 @@ namespace ts.formatting {
 
             // normally scanner returns the smallest available token
             // check the kind of context node to determine if scanner should have more greedy behavior and consume more text.
-            let expectedScanAction = 
+            let expectedScanAction =
                 shouldRescanGreaterThanToken(n)
                 ? ScanAction.RescanGreaterThanToken
                 : shouldRescanSlashToken(n) 
@@ -226,7 +228,7 @@ namespace ts.formatting {
             if (trailingTrivia) {
                 trailingTrivia = undefined;
             }
-            while(scanner.getStartPos() < endPos) {
+            while (scanner.getStartPos() < endPos) {
                 currentToken = scanner.scan();
                 if (!isTrivia(currentToken)) {
                     break;
@@ -261,7 +263,7 @@ namespace ts.formatting {
 
         function isOnToken(): boolean {
             Debug.assert(scanner !== undefined);
-            
+
             let current = (lastTokenInfo && lastTokenInfo.token.kind) || scanner.getToken();
             let startPos = (lastTokenInfo && lastTokenInfo.token.pos) || scanner.getStartPos();
             return startPos < endPos && current !== SyntaxKind.EndOfFileToken && !isTrivia(current);

tests/cases/fourslash/formatDocumentWithTrivia.ts

@@ -0,0 +1,51 @@
+/// <reference path="fourslash.ts" />
+
+////  
+////// whitespace below   
+////    
+////// whitespace above   
+////    
+////let x;
+////  
+////// abc
+////  
+////let y;
+////  
+////// whitespace above again
+////   
+////while (true) {
+////    while (true) {
+////    }
+////      
+////    // whitespace above   
+////}
+////  
+////// whitespace above again  
+////   
+////   
+
+format.document();
+
+verify.currentFileContentIs(`
+// whitespace below   
+
+// whitespace above   
+
+let x;
+
+// abc
+
+let y;
+
+// whitespace above again
+
+while (true) {
+    while (true) {
+    }
+
+    // whitespace above   
+}
+
+// whitespace above again  
+
+`);

tests/cases/fourslash/formatSelectionWithTrivia2.ts

@@ -0,0 +1,10 @@
+/// <reference path="fourslash.ts" />
+
+/////*begin*/;    
+////    
+/////*end*/    
+////    
+
+format.selection('begin', 'end');
+
+verify.currentFileContentIs(";\n\n\n    ");