Breakpoint span in variable declarations in new language service

Also updates the fourslash breakpoints baseline to be more readable

Author: sheetalkamat

Jakefile

@@ -55,6 +55,7 @@ var servicesSources = [
 ].map(function (f) {
     return path.join(compilerDirectory, f);
 }).concat([
+    "breakpoints.ts",
     "services.ts",
     "shims.ts",
     "signatureHelp.ts",

src/harness/fourslash.ts

@@ -985,13 +985,23 @@ module FourSlash {
             return item.parameters[currentParam];
         }
 
-        public getBreakpointStatementLocation(pos: number) {
+        private alignmentForExtraInfo = 50;
+
+        public getBreakpointStatementLocation(pos: number, prefixString: string) {
             this.taoInvalidReason = 'getBreakpointStatementLocation NYI';
 
             var spanInfo = this.languageService.getBreakpointStatementAtPosition(this.activeFile.fileName, pos);
-            var resultString = "\n**Pos: " + pos + " SpanInfo: " + JSON.stringify(spanInfo) + "\n** Statement: ";
-            if (spanInfo !== null) {
-                resultString = resultString + this.activeFile.content.substr(spanInfo.start(), spanInfo.length());
+            var resultString = "SpanInfo: " + JSON.stringify(spanInfo);
+            if (spanInfo) {
+                var spanString = this.activeFile.content.substr(spanInfo.start(), spanInfo.length());
+                var spanLineMap = ts.getLineStarts(spanString);
+                for (var i = 0; i < spanLineMap.length; i++) {
+                    if (!i) {
+                        resultString += "\n";
+                    }
+                    resultString += prefixString + spanString.substring(spanLineMap[i], spanLineMap[i + 1]);
+                }
+                resultString += "\n" + prefixString + ":=> (" + this.getLineColStringAtPosition(spanInfo.start()) + ") to (" + this.getLineColStringAtPosition(spanInfo.end()) + ")";
             }
             return resultString;
         }
@@ -1003,12 +1013,60 @@ module FourSlash {
                 "Breakpoint Locations for " + this.activeFile.fileName,
                 this.testData.globalOptions[testOptMetadataNames.baselineFile],
                 () => {
-                    var fileLength = this.languageServiceShimHost.getScriptSnapshot(this.activeFile.fileName).getLength();
+                    var fileLineMap = ts.getLineStarts(this.activeFile.content);
+                    var nextLine = 0;
                     var resultString = "";
-                    for (var pos = 0; pos < fileLength; pos++) {
-                        resultString = resultString + this.getBreakpointStatementLocation(pos);
+                    var currentLine: string;
+                    var previousSpanInfo: string;
+                    var startColumn: number;
+                    var length: number;
+                    var prefixString = "    >";
+
+                    var addSpanInfoString = () => {
+                        if (previousSpanInfo) {
+                            resultString += currentLine;
+                            var thisLineMarker = repeatString(startColumn, " ") + repeatString(length, "~");
+                            thisLineMarker += repeatString(this.alignmentForExtraInfo - thisLineMarker.length - prefixString.length + 1, " ");
+                            resultString += thisLineMarker;
+                            resultString += "=> Pos: (" + (pos - length) + " to " + (pos - 1) + ") ";
+                            resultString += " " + previousSpanInfo;
+                            previousSpanInfo = undefined;
+                        }
+                    };
+
+                    for (var pos = 0; pos < this.activeFile.content.length; pos++) {
+                        if (pos === 0 || pos === fileLineMap[nextLine]) {
+                            nextLine++;
+                            addSpanInfoString();
+                            if (resultString.length) {
+                                resultString += "\n--------------------------------";
+                            }
+                            currentLine = "\n" + nextLine.toString() + repeatString(3 - nextLine.toString().length, " ") + ">" + this.activeFile.content.substring(pos, fileLineMap[nextLine]) + "\n    ";
+                            startColumn = 0;
+                            length = 0;
+                        }
+                        var spanInfo = this.getBreakpointStatementLocation(pos, prefixString);
+                        if (previousSpanInfo && previousSpanInfo !== spanInfo) {
+                            addSpanInfoString();
+                            previousSpanInfo = spanInfo;
+                            startColumn = startColumn + length;
+                            length = 1;
+                        }
+                        else {
+                            previousSpanInfo = spanInfo;
+                            length++;
+                        }
                     }
+                    addSpanInfoString();
                     return resultString;
+
+                    function repeatString(count: number, char: string) {
+                        var result = "";
+                        for (var i = 0; i < count; i++) {
+                            result += char;
+                        }
+                        return result;
+                    }
                 },
                 true /* run immediately */);
         }
@@ -1056,7 +1114,7 @@ module FourSlash {
         }
 
         public printBreakpointLocation(pos: number) {
-            Harness.IO.log(this.getBreakpointStatementLocation(pos));
+            Harness.IO.log("\n**Pos: " + pos + " " + this.getBreakpointStatementLocation(pos, "  "));
         }
 
         public printBreakpointAtCurrentLocation() {
@@ -1502,7 +1560,7 @@ module FourSlash {
                 throw new Error('verifyCaretAtMarker failed - expected to be in file "' + pos.fileName + '", but was in file "' + this.activeFile.fileName + '"');
             }
             if (pos.position !== this.currentCaretPosition) {
-                throw new Error('verifyCaretAtMarker failed - expected to be at marker "/*' + markerName + '*/, but was at position ' + this.currentCaretPosition + '(' + this.getLineColStringAtCaret() + ')');
+                throw new Error('verifyCaretAtMarker failed - expected to be at marker "/*' + markerName + '*/, but was at position ' + this.currentCaretPosition + '(' + this.getLineColStringAtPosition(this.currentCaretPosition) + ')');
             }
         }
 
@@ -2102,8 +2160,8 @@ module FourSlash {
             return this.languageServiceShimHost.positionToZeroBasedLineCol(this.activeFile.fileName, this.currentCaretPosition).line + 1;
         }
 
-        private getLineColStringAtCaret() {
-            var pos = this.languageServiceShimHost.positionToZeroBasedLineCol(this.activeFile.fileName, this.currentCaretPosition);
+        private getLineColStringAtPosition(position: number) {
+            var pos = this.languageServiceShimHost.positionToZeroBasedLineCol(this.activeFile.fileName, position);
             return 'line ' + (pos.line + 1) + ', col ' + pos.character;
         }
 

src/services/breakpoints.ts

@@ -1082,4 +1082,93 @@ module TypeScript.Services.Breakpoints {
         var breakpointResolver = new BreakpointResolver(posLine, lineMap);
         return breakpointResolver.breakpointSpanOf(positionedToken);
     }
+}
+
+module ts.Breakpoints {
+    /**
+     * Get the breakpoint span in given sourceFile
+     */
+    export function spanInSourceFileAtLocation(sourceFile: SourceFile, position: number) {
+        // Cannot set breakpoint in dts file
+        if (sourceFile.flags & NodeFlags.DeclarationFile) {
+            return;
+        }
+
+        var tokenAtLocation = getTokenAtPosition(sourceFile, position);
+        var lineOfPosition = sourceFile.getLineAndCharacterFromPosition(position).line;
+        if (sourceFile.getLineAndCharacterFromPosition(tokenAtLocation.getStart()).line > lineOfPosition) {
+            // Get previous token if the token is returned starts on new line
+            // eg: var x =10; |--- curser is here
+            //     var y = 10; 
+            // token at position will return var keyword on second line as the token but we would like to use 
+            // token on same line if trailing trivia (comments or white spaces on same line) part of the last token on that line
+            tokenAtLocation = findPrecedingToken(tokenAtLocation.pos, sourceFile);
+        }
+
+        // Cannot set breakpoint in ambient declarations
+        if (isInAmbientContext(tokenAtLocation)) {
+            return;
+        }
+
+        // Get the span in the node based on its syntax
+        return spanInNode(tokenAtLocation);
+
+        function textSpan(startNode: Node, endNode?: Node) {
+            return TypeScript.TextSpan.fromBounds(startNode.getStart(), (endNode || startNode).getEnd());
+        }
+
+        function spanInNodeIfStartsOnSameLine(node: Node): TypeScript.TextSpan {
+            if (node && sourceFile.getLineAndCharacterFromPosition(position).line === sourceFile.getLineAndCharacterFromPosition(node.getStart()).line) {
+                return spanInNode(node);
+            }
+        }
+
+        function spanInNode(node: Node): TypeScript.TextSpan {
+            if (node) {
+                switch (node.kind) {
+                    case SyntaxKind.VariableStatement:
+                        return spanInVariableStatement(<VariableStatement>node);
+
+                    case SyntaxKind.VariableDeclaration:
+                        return spanInVariableDeclaration(<VariableDeclaration>node);
+
+                    case SyntaxKind.SemicolonToken:
+                    case SyntaxKind.EndOfFileToken:
+                        return spanInNodeIfStartsOnSameLine(findPrecedingToken(node.pos, sourceFile));
+
+                    default:
+                        // Default go to parent to set the breakpoint
+                        return spanInNode(node.parent);
+                }
+            }
+
+            function spanInVariableDeclaration(variableDeclaration: VariableDeclaration): TypeScript.TextSpan {
+                var isParentVariableStatement = variableDeclaration.parent.kind === SyntaxKind.VariableStatement;
+                var isfirstDeclarationOfVariableStatement = isParentVariableStatement &&
+                    (<VariableStatement>variableDeclaration.parent).declarations[0] === variableDeclaration;
+
+                // Breakpoint is possible in variableDeclaration only if there is initialization
+                if (variableDeclaration.initializer) {
+                    if (isfirstDeclarationOfVariableStatement) {
+                        // First declaration - include var keyword
+                        return textSpan(variableDeclaration.parent, variableDeclaration);
+                    }
+                    else {
+                        // Span only on this declaration
+                        return textSpan(variableDeclaration);
+                    }
+                }
+                else if (!isfirstDeclarationOfVariableStatement && isParentVariableStatement) {
+                    // If we cant set breakpoint on this declaration, set it on previous one
+                    var variableStatement = <VariableStatement>variableDeclaration.parent;
+                    var indexOfCurrentDeclaration = indexOf(variableStatement.declarations, variableDeclaration);
+                    return spanInVariableDeclaration(variableStatement.declarations[indexOfCurrentDeclaration - 1]);
+                }
+            }
+
+            function spanInVariableStatement(variableStatement: VariableStatement): TypeScript.TextSpan {
+                return spanInVariableDeclaration(variableStatement.declarations[0]);
+            }
+        }
+   }
 }

src/services/services.ts

@@ -4737,9 +4737,7 @@ module ts {
         function getBreakpointStatementAtPosition(filename: string, position: number) {
             // doesn't use compiler - no need to synchronize with host
             filename = TypeScript.switchToForwardSlashes(filename);
-
-            var syntaxtree = getSyntaxTree(filename);
-            return TypeScript.Services.Breakpoints.getBreakpointLocation(syntaxtree, position);
+            return Breakpoints.spanInSourceFileAtLocation(getCurrentSourceFile(filename), position);
         }
 
         function getNavigationBarItems(filename: string): NavigationBarItem[] {

tests/baselines/reference/bpSpan_variables.baseline

@@ -0,0 +1,23 @@
+
+1  >var a = 10;
+
+    ~~~~~~~~~~~~                                  => Pos: (0 to 11)  SpanInfo: {"start":0,"length":10}
+    >var a = 10
+    >:=> (line 1, col 0) to (line 1, col 10)
+--------------------------------
+2  >var b;
+
+    ~~~~~~~                                       => Pos: (12 to 18)  SpanInfo: undefined
+--------------------------------
+3  >var c = 10, d, e;
+
+    ~~~~~~~~~~~~~~~~~~                            => Pos: (19 to 36)  SpanInfo: {"start":19,"length":10}
+    >var c = 10
+    >:=> (line 3, col 0) to (line 3, col 10)
+--------------------------------
+4  >var c2, d2 = 10;
+    ~~~~~~~                                       => Pos: (37 to 43)  SpanInfo: undefined
+4  >var c2, d2 = 10;
+           ~~~~~~~~~                              => Pos: (44 to 52)  SpanInfo: {"start":45,"length":7}
+    >d2 = 10
+    >:=> (line 4, col 8) to (line 4, col 15)