microsoft · CyrusNajmabadi · Sep 17, 2014 · Sep 16, 2014 · Sep 17, 2014 · Sep 17, 2014
diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
@@ -65,7 +65,8 @@ module ts {
             symbolToString: symbolToString,
             getAugmentedPropertiesOfApparentType: getAugmentedPropertiesOfApparentType,
             getRootSymbol: getRootSymbol,
-            getContextualType: getContextualType
+            getContextualType: getContextualType,
+            getFullyQualifiedName: getFullyQualifiedName
         };
 
         var undefinedSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "undefined");

diff --git a/src/compiler/types.ts b/src/compiler/types.ts
@@ -634,6 +634,7 @@ module ts {
         getApparentType(type: Type): ApparentType;
         typeToString(type: Type, enclosingDeclaration?: Node, flags?: TypeFormatFlags): string;
         symbolToString(symbol: Symbol, enclosingDeclaration?: Node, meaning?: SymbolFlags): string;
+        getFullyQualifiedName(symbol: Symbol): string;
         getAugmentedPropertiesOfApparentType(type: Type): Symbol[];
         getRootSymbol(symbol: Symbol): Symbol;
         getContextualType(node: Node): Type;

diff --git a/src/harness/fourslash.ts b/src/harness/fourslash.ts
@@ -898,6 +898,44 @@ module FourSlash {
             }
         }
 
+        private validate(name: string, expected: string, actual: string) {
+            if (expected && expected !== actual) {
+                throw new Error("Expected " + name + " '" + expected + "'.  Got '" + actual + "' instead.");
+            }
+        }
+
+        public verifyRenameInfoSucceeded(displayName?: string, fullDisplayName?: string, kind?: string, kindModifiers?: string) {
+            var renameInfo = this.languageService.getRenameInfo(this.activeFile.fileName, this.currentCaretPosition);
+            if (!renameInfo.canRename) {
+                throw new Error("Rename did not succeed");
+            }
+
+            this.validate("displayName", displayName, renameInfo.displayName);
+            this.validate("fullDisplayName", fullDisplayName, renameInfo.fullDisplayName);
+            this.validate("kind", kind, renameInfo.kind);
+            this.validate("kindModifiers", kindModifiers, renameInfo.kindModifiers);
+
+            if (this.getRanges().length !== 1) {
+                throw new Error("Expected a single range to be selected in the test file.");
+            }
+
+            var expectedRange = this.getRanges()[0];
+            if (renameInfo.triggerSpan.start() !== expectedRange.start ||
+                renameInfo.triggerSpan.end() !== expectedRange.end) {
+                throw new Error("Expected triggerSpan [" + expectedRange.start + "," + expectedRange.end + ").  Got [" +
+                    renameInfo.triggerSpan.start() + "," + renameInfo.triggerSpan.end() + ") instead.");
+            }
+        }
+
+        public verifyRenameInfoFailed(message?: string) {
+            var renameInfo = this.languageService.getRenameInfo(this.activeFile.fileName, this.currentCaretPosition);
+            if (renameInfo.canRename) {
+                throw new Error("Rename was expected to fail");
+            }
+
+            this.validate("error", message, renameInfo.localizedErrorMessage);
+        }
+
         //private getFormalParameter() {
         //    var help = this.languageService.getSignatureHelpItems(this.activeFile.fileName, this.currentCaretPosition);
         //    return help.formal;

diff --git a/src/services/services.ts b/src/services/services.ts
@@ -3896,6 +3896,32 @@ module ts {
             return null;
         }
 
+        function getRenameInfo(fileName: string, position: number): RenameInfo {
+            synchronizeHostData();
+
+            fileName = TypeScript.switchToForwardSlashes(fileName);
+            var sourceFile = getSourceFile(fileName);
+
+            var node = getNodeAtPosition(sourceFile, position);
+
+            // Can only rename an identifier.
+            if (node && node.kind === SyntaxKind.Identifier) {
+                var symbol = typeInfoResolver.getSymbolInfo(node);
+
+                // Only allow a symbol to be renamed if it actually has at least one declaration.
+                if (symbol && symbol.getDeclarations() && symbol.getDeclarations().length > 0) {
+                    var kind = getSymbolKind(symbol);
+                    if (kind) {
+                        return RenameInfo.Create(symbol.name, typeInfoResolver.getFullyQualifiedName(symbol), kind,
+                            getNodeModifiers(symbol.getDeclarations()[0]),
+                            new TypeScript.TextSpan(node.getStart(), node.getWidth()));
+                    }
+                }
+            }
+
+            return RenameInfo.CreateError(getLocaleSpecificMessage(Diagnostics.You_cannot_rename_this_element.key));
+        }
+
         return {
             dispose: dispose,
             cleanupSemanticCache: cleanupSemanticCache,
@@ -3916,7 +3942,7 @@ module ts {
             getNameOrDottedNameSpan: getNameOrDottedNameSpan,
             getBreakpointStatementAtPosition: getBreakpointStatementAtPosition,
             getNavigateToItems: getNavigateToItems,
-            getRenameInfo: (fileName, position): RenameInfo => RenameInfo.CreateError(getLocaleSpecificMessage(Diagnostics.You_cannot_rename_this_element.key)),
+            getRenameInfo: getRenameInfo,
             getNavigationBarItems: getNavigationBarItems,
             getOutliningSpans: getOutliningSpans,
             getTodoComments: getTodoComments,

diff --git a/tests/cases/fourslash/fourslash.ts b/tests/cases/fourslash/fourslash.ts
@@ -404,6 +404,14 @@ module FourSlashInterface {
         public semanticClassificationsAre(...classifications: { classificationType: string; text: string }[]) {
             FourSlash.currentTestState.verifySemanticClassifications(classifications);
         }
+
+        public renameInfoSucceeded(displayName?: string, fullDisplayName?: string, kind?: string, kindModifiers?: string) {
+            FourSlash.currentTestState.verifyRenameInfoSucceeded(displayName, fullDisplayName, kind, kindModifiers)
+        }
+
+        public renameInfoFailed(message?: string) {
+            FourSlash.currentTestState.verifyRenameInfoFailed(message)
+        }
     }
 
     export class edit {

diff --git a/tests/cases/fourslash/getRenameInfoTests1.ts b/tests/cases/fourslash/getRenameInfoTests1.ts
@@ -0,0 +1,8 @@
+/// <reference path="fourslash.ts"/>
+
+////class [|/**/C|] {
+////
+////}
+
+goTo.marker("");
+verify.renameInfoSucceeded("C");
diff --git a/tests/cases/fourslash/getRenameInfoTests2.ts b/tests/cases/fourslash/getRenameInfoTests2.ts
@@ -0,0 +1,8 @@
+/// <reference path="fourslash.ts"/>
+
+/////**/class C {
+////
+////}
+
+goTo.marker("");
+verify.renameInfoFailed();