Extract method

.vscode/tasks.json

@@ -18,6 +18,13 @@
             "problemMatcher": [
                 "$tsc"
             ]
+        },
+        {
+            "taskName": "tests",
+            "showOutput": "silent",
+            "problemMatcher": [
+                "$tsc"
+            ]
         }
     ]
 }

Jakefile.js

@@ -133,6 +133,7 @@ var harnessSources = harnessCoreSources.concat([
     "projectErrors.ts",
     "matchFiles.ts",
     "initializeTSConfig.ts",
+    "extractMethods.ts",
     "printer.ts",
     "textChanges.ts",
     "telemetry.ts",

src/compiler/checker.ts

@@ -223,11 +223,10 @@ namespace ts {
             getSuggestionForNonexistentProperty: (node, type) => unescapeLeadingUnderscores(getSuggestionForNonexistentProperty(node, type)),
             getSuggestionForNonexistentSymbol: (location, name, meaning) => unescapeLeadingUnderscores(getSuggestionForNonexistentSymbol(location, escapeLeadingUnderscores(name), meaning)),
             getBaseConstraintOfType,
-            getJsxNamespace: () => unescapeLeadingUnderscores(getJsxNamespace()),
-            resolveNameAtLocation(location: Node, name: string, meaning: SymbolFlags): Symbol | undefined {
-                location = getParseTreeNode(location);
-                return resolveName(location, escapeLeadingUnderscores(name), meaning, /*nameNotFoundMessage*/ undefined, escapeLeadingUnderscores(name));
+            resolveName(name, location, meaning) {
+                return resolveName(location, name as __String, meaning, /*nameNotFoundMessage*/ undefined, /*nameArg*/ undefined);
             },
+            getJsxNamespace: () => unescapeLeadingUnderscores(getJsxNamespace()),
         };
 
         const tupleTypes: GenericType[] = [];

src/compiler/diagnosticMessages.json

@@ -3673,5 +3673,15 @@
     "Convert function '{0}' to class": {
         "category": "Message",
         "code": 95002
+    },
+
+    "Extract function": {
+        "category": "Message",
+        "code": 95003
+    },
+
+    "Extract function into '{0}'": {
+        "category": "Message",
+        "code": 95004
     }
 }

src/compiler/transformers/es2015.ts

@@ -394,7 +394,7 @@ namespace ts {
         function shouldVisitNode(node: Node): boolean {
             return (node.transformFlags & TransformFlags.ContainsES2015) !== 0
                 || convertedLoopState !== undefined
-                || (hierarchyFacts & HierarchyFacts.ConstructorWithCapturedSuper && isStatement(node))
+                || (hierarchyFacts & HierarchyFacts.ConstructorWithCapturedSuper && isStatementOrBlock(node))
                 || (isIterationStatement(node, /*lookInLabeledStatements*/ false) && shouldConvertIterationStatementBody(node))
                 || isTypeScriptClassWrapper(node);
         }

src/compiler/types.ts

@@ -2606,9 +2606,8 @@ namespace ts {
          * Does not include properties of primitive types.
          */
         /* @internal */ getAllPossiblePropertiesOfType(type: Type): Symbol[];
-
+        /* @internal */ resolveName(name: string, location: Node, meaning: SymbolFlags): Symbol | undefined;
         /* @internal */ getJsxNamespace(): string;
-        /* @internal */ resolveNameAtLocation(location: Node, name: string, meaning: SymbolFlags): Symbol | undefined;
     }
 
     export enum NodeBuilderFlags {

src/compiler/utilities.ts

@@ -693,7 +693,7 @@ namespace ts {
                 // At this point, node is either a qualified name or an identifier
                 Debug.assert(node.kind === SyntaxKind.Identifier || node.kind === SyntaxKind.QualifiedName || node.kind === SyntaxKind.PropertyAccessExpression,
                     "'node' was expected to be a qualified name, identifier or property access in 'isPartOfTypeNode'.");
-                // falls through
+            // falls through
             case SyntaxKind.QualifiedName:
             case SyntaxKind.PropertyAccessExpression:
             case SyntaxKind.ThisKeyword:
@@ -968,7 +968,7 @@ namespace ts {
                     if (!includeArrowFunctions) {
                         continue;
                     }
-                    // falls through
+                // falls through
                 case SyntaxKind.FunctionDeclaration:
                 case SyntaxKind.FunctionExpression:
                 case SyntaxKind.ModuleDeclaration:
@@ -1027,7 +1027,7 @@ namespace ts {
                     if (!stopOnFunctions) {
                         continue;
                     }
-                    // falls through
+                // falls through
                 case SyntaxKind.PropertyDeclaration:
                 case SyntaxKind.PropertySignature:
                 case SyntaxKind.MethodDeclaration:
@@ -1211,7 +1211,7 @@ namespace ts {
                 if (node.parent.kind === SyntaxKind.TypeQuery || isJSXTagName(node)) {
                     return true;
                 }
-                // falls through
+            // falls through
             case SyntaxKind.NumericLiteral:
             case SyntaxKind.StringLiteral:
             case SyntaxKind.ThisKeyword:
@@ -1499,8 +1499,8 @@ namespace ts {
                 parent.parent.kind === SyntaxKind.VariableStatement;
             const variableStatementNode =
                 isInitializerOfVariableDeclarationInStatement ? parent.parent.parent :
-                isVariableOfVariableDeclarationStatement ? parent.parent :
-                undefined;
+                    isVariableOfVariableDeclarationStatement ? parent.parent :
+                        undefined;
             if (variableStatementNode) {
                 getJSDocCommentsAndTagsWorker(variableStatementNode);
             }
@@ -1614,7 +1614,7 @@ namespace ts {
         if (isInJavaScriptFile(node)) {
             if (node.type && node.type.kind === SyntaxKind.JSDocVariadicType ||
                 forEach(getJSDocParameterTags(node),
-                        t => t.typeExpression && t.typeExpression.type.kind === SyntaxKind.JSDocVariadicType)) {
+                    t => t.typeExpression && t.typeExpression.type.kind === SyntaxKind.JSDocVariadicType)) {
                 return true;
             }
         }
@@ -1907,7 +1907,7 @@ namespace ts {
                 if (node.asteriskToken) {
                     flags |= FunctionFlags.Generator;
                 }
-                // falls through
+            // falls through
             case SyntaxKind.ArrowFunction:
                 if (hasModifier(node, ModifierFlags.Async)) {
                     flags |= FunctionFlags.Async;
@@ -5123,6 +5123,19 @@ namespace ts {
         return isUnaryExpressionKind(skipPartiallyEmittedExpressions(node).kind);
     }
 
+    /* @internal */
+    export function isUnaryExpressionWithWrite(expr: Node): expr is PrefixUnaryExpression | PostfixUnaryExpression {
+        switch (expr.kind) {
+            case SyntaxKind.PostfixUnaryExpression:
+                return true;
+            case SyntaxKind.PrefixUnaryExpression:
+                return (<PrefixUnaryExpression>expr).operator === SyntaxKind.PlusPlusToken ||
+                    (<PrefixUnaryExpression>expr).operator === SyntaxKind.MinusMinusToken;
+            default:
+                return false;
+        }
+    }
+
     function isExpressionKind(kind: SyntaxKind) {
         return kind === SyntaxKind.ConditionalExpression
             || kind === SyntaxKind.YieldExpression
@@ -5337,7 +5350,25 @@ namespace ts {
         const kind = node.kind;
         return isStatementKindButNotDeclarationKind(kind)
             || isDeclarationStatementKind(kind)
-            || kind === SyntaxKind.Block;
+            || isBlockStatement(node);
+    }
+
+    /* @internal */
+    export function isStatementOrBlock(node: Node): node is Statement {
+        const kind = node.kind;
+        return isStatementKindButNotDeclarationKind(kind)
+            || isDeclarationStatementKind(kind)
+            || node.kind === SyntaxKind.Block;
+    }
+
+    function isBlockStatement(node: Node): node is Block {
+        if (node.kind !== SyntaxKind.Block) return false;
+        if (node.parent !== undefined) {
+            if (node.parent.kind === SyntaxKind.TryStatement || node.parent.kind === SyntaxKind.CatchClause) {
+                return false;
+            }
+        }
+        return !isFunctionBlock(node);
     }
 
     // Module references

src/harness/fourslash.ts

@@ -187,6 +187,9 @@ namespace FourSlash {
 
         // The current caret position in the active file
         public currentCaretPosition = 0;
+        // The position of the end of the current selection, or -1 if nothing is selected
+        public selectionEnd = -1;
+
         public lastKnownMarker = "";
 
         // The file that's currently 'opened'
@@ -433,11 +436,19 @@ namespace FourSlash {
 
         public goToPosition(pos: number) {
             this.currentCaretPosition = pos;
+            this.selectionEnd = -1;
+        }
+
+        public select(startMarker: string, endMarker: string) {
+            const start = this.getMarkerByName(startMarker), end = this.getMarkerByName(endMarker);
+            this.goToPosition(start.position);
+            this.selectionEnd = end.position;
         }
 
         public moveCaretRight(count = 1) {
             this.currentCaretPosition += count;
             this.currentCaretPosition = Math.min(this.currentCaretPosition, this.getFileContent(this.activeFile.fileName).length);
+            this.selectionEnd = -1;
         }
 
         // Opens a file given its 0-based index or fileName
@@ -980,9 +991,9 @@ namespace FourSlash {
             }
 
             for (const reference of expectedReferences) {
-                const {fileName, start, end} = reference;
+                const { fileName, start, end } = reference;
                 if (reference.marker && reference.marker.data) {
-                    const {isWriteAccess, isDefinition} = reference.marker.data;
+                    const { isWriteAccess, isDefinition } = reference.marker.data;
                     this.verifyReferencesWorker(actualReferences, fileName, start, end, isWriteAccess, isDefinition);
                 }
                 else {
@@ -1193,7 +1204,7 @@ namespace FourSlash {
             displayParts: ts.SymbolDisplayPart[],
             documentation: ts.SymbolDisplayPart[],
             tags: ts.JSDocTagInfo[]
-            ) {
+        ) {
 
             const actualQuickInfo = this.languageService.getQuickInfoAtPosition(this.activeFile.fileName, this.currentCaretPosition);
             assert.equal(actualQuickInfo.kind, kind, this.messageAtLastKnownMarker("QuickInfo kind"));
@@ -1789,19 +1800,16 @@ namespace FourSlash {
             // We get back a set of edits, but langSvc.editScript only accepts one at a time. Use this to keep track
             // of the incremental offset from each edit to the next. We assume these edit ranges don't overlap
 
-            edits = edits.sort((a, b) => a.span.start - b.span.start);
-            for (let i = 0; i < edits.length - 1; i++) {
-                const firstEditSpan = edits[i].span;
-                const firstEditEnd = firstEditSpan.start + firstEditSpan.length;
-                assert.isTrue(firstEditEnd <= edits[i + 1].span.start);
-            }
+            // Copy this so we don't ruin someone else's copy
+            edits = JSON.parse(JSON.stringify(edits));
 
             // Get a snapshot of the content of the file so we can make sure any formatting edits didn't destroy non-whitespace characters
             const oldContent = this.getFileContent(fileName);
             let runningOffset = 0;
 
-            for (const edit of edits) {
-                const offsetStart = edit.span.start + runningOffset;
+            for (let i = 0; i < edits.length; i++) {
+                const edit = edits[i];
+                const offsetStart = edit.span.start;
                 const offsetEnd = offsetStart + edit.span.length;
                 this.editScriptAndUpdateMarkers(fileName, offsetStart, offsetEnd, edit.newText);
                 const editDelta = edit.newText.length - edit.span.length;
@@ -1816,8 +1824,13 @@ namespace FourSlash {
                     }
                 }
                 runningOffset += editDelta;
-                // TODO: Consider doing this at least some of the time for higher fidelity. Currently causes a failure (bug 707150)
-                // this.languageService.getScriptLexicalStructure(fileName);
+
+                // Update positions of any future edits affected by this change
+                for (let j = i + 1; j < edits.length; j++) {
+                    if (edits[j].span.start >= edits[i].span.start) {
+                        edits[j].span.start += editDelta;
+                    }
+                }
             }
 
             if (isFormattingEdit) {
@@ -1901,7 +1914,7 @@ namespace FourSlash {
             this.goToPosition(len);
         }
 
-        public goToRangeStart({fileName, start}: Range) {
+        public goToRangeStart({ fileName, start }: Range) {
             this.openFile(fileName);
             this.goToPosition(start);
         }
@@ -2075,7 +2088,7 @@ namespace FourSlash {
             return result;
         }
 
-        private rangeText({fileName, start, end}: Range): string {
+        private rangeText({ fileName, start, end }: Range): string {
             return this.getFileContent(fileName).slice(start, end);
         }
 
@@ -2361,7 +2374,7 @@ namespace FourSlash {
         private applyCodeActions(actions: ts.CodeAction[], index?: number): void {
             if (index === undefined) {
                 if (!(actions && actions.length === 1)) {
-                    this.raiseError(`Should find exactly one codefix, but ${actions ? actions.length : "none"} found. ${actions ? actions.map(a => `${Harness.IO.newLine()} "${a.description}"`) : "" }`);
+                    this.raiseError(`Should find exactly one codefix, but ${actions ? actions.length : "none"} found. ${actions ? actions.map(a => `${Harness.IO.newLine()} "${a.description}"`) : ""}`);
                 }
                 index = 0;
             }
@@ -2736,6 +2749,30 @@ namespace FourSlash {
             }
         }
 
+        private getSelection() {
+            return ({
+                pos: this.currentCaretPosition,
+                end: this.selectionEnd === -1 ? this.currentCaretPosition : this.selectionEnd
+            });
+        }
+
+        public verifyRefactorAvailable(negative: boolean, name?: string, subName?: string) {
+            const selection = this.getSelection();
+
+            let refactors = this.languageService.getApplicableRefactors(this.activeFile.fileName, selection) || [];
+            if (name) {
+                refactors = refactors.filter(r => r.name === name && (subName === undefined || r.actions.some(a => a.name === subName)));
+            }
+            const isAvailable = refactors.length > 0;
+
+            if (negative && isAvailable) {
+                this.raiseError(`verifyApplicableRefactorAvailableForRange failed - expected no refactor but found some.`);
+            }
+            else if (!negative && !isAvailable) {
+                this.raiseError(`verifyApplicableRefactorAvailableForRange failed - expected a refactor but found none.`);
+            }
+        }
+
         public verifyApplicableRefactorAvailableForRange(negative: boolean) {
             const ranges = this.getRanges();
             if (!(ranges && ranges.length === 1)) {
@@ -2752,6 +2789,20 @@ namespace FourSlash {
             }
         }
 
+        public applyRefactor(refactorName: string, actionName: string) {
+            const range = this.getSelection();
+            const refactors = this.languageService.getApplicableRefactors(this.activeFile.fileName, range);
+            const refactor = ts.find(refactors, r => r.name === refactorName);
+            if (!refactor) {
+                this.raiseError(`The expected refactor: ${refactorName} is not available at the marker location.`);
+            }
+
+            const editInfo = this.languageService.getEditsForRefactor(this.activeFile.fileName, this.formatCodeSettings, range, refactorName, actionName);
+            for (const edit of editInfo.edits) {
+                this.applyEdits(edit.fileName, edit.textChanges, /*isFormattingEdit*/ false);
+            }
+        }
+
         public verifyFileAfterApplyingRefactorAtMarker(
             markerName: string,
             expectedContent: string,
@@ -3496,6 +3547,10 @@ namespace FourSlashInterface {
         public file(indexOrName: any, content?: string, scriptKindName?: string): void {
             this.state.openFile(indexOrName, content, scriptKindName);
         }
+
+        public select(startMarker: string, endMarker: string) {
+            this.state.select(startMarker, endMarker);
+        }
     }
 
     export class VerifyNegatable {
@@ -3617,6 +3672,10 @@ namespace FourSlashInterface {
         public applicableRefactorAvailableForRange() {
             this.state.verifyApplicableRefactorAvailableForRange(this.negative);
         }
+
+        public refactorAvailable(name?: string, subName?: string) {
+            this.state.verifyRefactorAvailable(this.negative, name, subName);
+        }
     }
 
     export class Verify extends VerifyNegatable {
@@ -4012,6 +4071,10 @@ namespace FourSlashInterface {
         public disableFormatting() {
             this.state.enableFormatting = false;
         }
+
+        public applyRefactor(refactorName: string, actionName: string) {
+            this.state.applyRefactor(refactorName, actionName);
+        }
     }
 
     export class Debug {