Merge pull request microsoft#13660 from Microsoft/rename

Andy · web-flow · commit 8144c89c9c63 · 2017-01-24T15:18:38.000-08:00
Simplify code in 'rename'
diff --git a/src/services/rename.ts b/src/services/rename.ts
@@ -1,98 +1,92 @@
 /* @internal */
 namespace ts.Rename {
     export function getRenameInfo(typeChecker: TypeChecker, defaultLibFileName: string, getCanonicalFileName: (fileName: string) => string, sourceFile: SourceFile, position: number): RenameInfo {
-        const canonicalDefaultLibName = getCanonicalFileName(ts.normalizePath(defaultLibFileName));
-
+        const getCanonicalDefaultLibName = memoize(() => getCanonicalFileName(ts.normalizePath(defaultLibFileName)));
         const node = getTouchingWord(sourceFile, position, /*includeJsDocComment*/ true);
+        const renameInfo = node && nodeIsEligibleForRename(node)
+            ? getRenameInfoForNode(node, typeChecker, sourceFile, isDefinedInLibraryFile)
+            : undefined;
+        return renameInfo || getRenameInfoError(Diagnostics.You_cannot_rename_this_element);
 
-        if (node) {
-            if (node.kind === SyntaxKind.Identifier ||
-                node.kind === SyntaxKind.StringLiteral ||
-                isLiteralNameOfPropertyDeclarationOrIndexAccess(node) ||
-                isThis(node)) {
-                const symbol = typeChecker.getSymbolAtLocation(node);
+        function isDefinedInLibraryFile(declaration: Node) {
+            if (!defaultLibFileName) {
+                return false;
+            }
+
+            const sourceFile = declaration.getSourceFile();
+            const canonicalName = getCanonicalFileName(ts.normalizePath(sourceFile.fileName));
+            return canonicalName === getCanonicalDefaultLibName();
+        }
+    }
 
-                // Only allow a symbol to be renamed if it actually has at least one declaration.
-                if (symbol) {
-                    const declarations = symbol.getDeclarations();
-                    if (declarations && declarations.length > 0) {
-                        // Disallow rename for elements that are defined in the standard TypeScript library.
-                        if (forEach(declarations, isDefinedInLibraryFile)) {
-                            return getRenameInfoError(getLocaleSpecificMessage(Diagnostics.You_cannot_rename_elements_that_are_defined_in_the_standard_TypeScript_library));
-                        }
+    function getRenameInfoForNode(node: Node, typeChecker: TypeChecker, sourceFile: SourceFile, isDefinedInLibraryFile: (declaration: Node) => boolean): RenameInfo | undefined {
+        const symbol = typeChecker.getSymbolAtLocation(node);
 
-                        const displayName = stripQuotes(getDeclaredName(typeChecker, symbol, node));
-                        const kind = SymbolDisplay.getSymbolKind(typeChecker, symbol, node);
-                        if (kind) {
-                            return {
-                                canRename: true,
-                                kind,
-                                displayName,
-                                localizedErrorMessage: undefined,
-                                fullDisplayName: typeChecker.getFullyQualifiedName(symbol),
-                                kindModifiers: SymbolDisplay.getSymbolModifiers(symbol),
-                                triggerSpan: createTriggerSpanForNode(node, sourceFile)
-                            };
-                        }
-                    }
+        // Only allow a symbol to be renamed if it actually has at least one declaration.
+        if (symbol) {
+            const declarations = symbol.getDeclarations();
+            if (declarations && declarations.length > 0) {
+                // Disallow rename for elements that are defined in the standard TypeScript library.
+                if (some(declarations, isDefinedInLibraryFile)) {
+                    return getRenameInfoError(Diagnostics.You_cannot_rename_elements_that_are_defined_in_the_standard_TypeScript_library);
                 }
-                else if (node.kind === SyntaxKind.StringLiteral) {
-                    const type = getStringLiteralTypeForNode(<StringLiteral>node, typeChecker);
-                    if (type) {
-                        if (isDefinedInLibraryFile(node)) {
-                            return getRenameInfoError(getLocaleSpecificMessage(Diagnostics.You_cannot_rename_elements_that_are_defined_in_the_standard_TypeScript_library));
-                        }
-                        else {
-                            const displayName = stripQuotes(type.text);
-                            return {
-                                canRename: true,
-                                kind: ScriptElementKind.variableElement,
-                                displayName,
-                                localizedErrorMessage: undefined,
-                                fullDisplayName: displayName,
-                                kindModifiers: ScriptElementKindModifier.none,
-                                triggerSpan: createTriggerSpanForNode(node, sourceFile)
-                            };
-                        }
-                    }
+
+                const displayName = stripQuotes(getDeclaredName(typeChecker, symbol, node));
+                const kind = SymbolDisplay.getSymbolKind(typeChecker, symbol, node);
+                return kind ? getRenameInfoSuccess(displayName, typeChecker.getFullyQualifiedName(symbol), kind, SymbolDisplay.getSymbolModifiers(symbol), node, sourceFile) : undefined;
+            }
+        }
+        else if (node.kind === SyntaxKind.StringLiteral) {
+            const type = getStringLiteralTypeForNode(<StringLiteral>node, typeChecker);
+            if (type) {
+                if (isDefinedInLibraryFile(node)) {
+                    return getRenameInfoError(Diagnostics.You_cannot_rename_elements_that_are_defined_in_the_standard_TypeScript_library);
                 }
+
+                const displayName = stripQuotes(type.text);
+                return getRenameInfoSuccess(displayName, displayName, ScriptElementKind.variableElement, ScriptElementKindModifier.none, node, sourceFile);
             }
         }
+    }
 
-        return getRenameInfoError(getLocaleSpecificMessage(Diagnostics.You_cannot_rename_this_element));
+    function getRenameInfoSuccess(displayName: string, fullDisplayName: string, kind: string, kindModifiers: string, node: Node, sourceFile: SourceFile): RenameInfo {
+        return {
+            canRename: true,
+            kind,
+            displayName,
+            localizedErrorMessage: undefined,
+            fullDisplayName,
+            kindModifiers,
+            triggerSpan: createTriggerSpanForNode(node, sourceFile)
+        };
+    }
 
-        function getRenameInfoError(localizedErrorMessage: string): RenameInfo {
-            return {
-                canRename: false,
-                localizedErrorMessage: localizedErrorMessage,
-                displayName: undefined,
-                fullDisplayName: undefined,
-                kind: undefined,
-                kindModifiers: undefined,
-                triggerSpan: undefined
-            };
-        }
+    function getRenameInfoError(diagnostic: DiagnosticMessage): RenameInfo {
+        return {
+            canRename: false,
+            localizedErrorMessage: getLocaleSpecificMessage(diagnostic),
+            displayName: undefined,
+            fullDisplayName: undefined,
+            kind: undefined,
+            kindModifiers: undefined,
+            triggerSpan: undefined
+        };
+    }
 
-        function isDefinedInLibraryFile(declaration: Node) {
-            if (defaultLibFileName) {
-                const sourceFile = declaration.getSourceFile();
-                const canonicalName = getCanonicalFileName(ts.normalizePath(sourceFile.fileName));
-                if (canonicalName === canonicalDefaultLibName) {
-                    return true;
-                }
-            }
-            return false;
+    function createTriggerSpanForNode(node: Node, sourceFile: SourceFile) {
+        let start = node.getStart(sourceFile);
+        let width = node.getWidth(sourceFile);
+        if (node.kind === SyntaxKind.StringLiteral) {
+            // Exclude the quotes
+            start += 1;
+            width -= 2;
         }
+        return createTextSpan(start, width);
+    }
 
-        function createTriggerSpanForNode(node: Node, sourceFile: SourceFile) {
-            let start = node.getStart(sourceFile);
-            let width = node.getWidth(sourceFile);
-            if (node.kind === SyntaxKind.StringLiteral) {
-                // Exclude the quotes
-                start += 1;
-                width -= 2;
-            }
-            return createTextSpan(start, width);
-        }
+    function nodeIsEligibleForRename(node: Node) {
+        return node.kind === SyntaxKind.Identifier || node.kind === SyntaxKind.StringLiteral ||
+            isLiteralNameOfPropertyDeclarationOrIndexAccess(node) ||
+            isThis(node);
     }
 }
