From 5bcb8fa9fa33f73bd62bc09b2e561c84e42905ee Mon Sep 17 00:00:00 2001
From: Andy Hanson <anhans@microsoft.com>
Date: Tue, 21 Mar 2017 13:24:39 -0700
Subject: [PATCH] Don't need types to handle string literals

---
 src/services/findAllReferences.ts | 27 +++++++--------------------
 src/services/rename.ts            | 13 +++++--------
 src/services/utilities.ts         |  9 ---------
 3 files changed, 12 insertions(+), 37 deletions(-)

diff --git a/src/services/findAllReferences.ts b/src/services/findAllReferences.ts
index ba7a6917631..a40af45a25c 100644
--- a/src/services/findAllReferences.ts
+++ b/src/services/findAllReferences.ts
@@ -279,7 +279,7 @@ namespace ts.FindAllReferences.Core {
         if (!symbol) {
             // String literal might be a property (and thus have a symbol), so do this here rather than in getReferencedSymbolsSpecial.
             if (!options.implementations && node.kind === SyntaxKind.StringLiteral) {
-                return getReferencesForStringLiteral(<StringLiteral>node, sourceFiles, checker, cancellationToken);
+                return getReferencesForStringLiteral(<StringLiteral>node, sourceFiles, cancellationToken);
             }
             // Can't have references to something that we have no symbol for.
             return undefined;
@@ -1328,19 +1328,13 @@ namespace ts.FindAllReferences.Core {
         }
     }
 
-    function getReferencesForStringLiteral(node: StringLiteral, sourceFiles: SourceFile[], checker: TypeChecker, cancellationToken: CancellationToken): SymbolAndEntries[] {
-        const type = getStringLiteralTypeForNode(node, checker);
-
-        if (!type) {
-            // nothing to do here. moving on
-            return undefined;
-        }
-
+    function getReferencesForStringLiteral(node: StringLiteral, sourceFiles: SourceFile[], cancellationToken: CancellationToken): SymbolAndEntries[] {
         const references: NodeEntry[] = [];
 
         for (const sourceFile of sourceFiles) {
-            const possiblePositions = getPossibleSymbolReferencePositions(sourceFile, type.text, sourceFile.getStart(), sourceFile.getEnd(), cancellationToken);
-            getReferencesForStringLiteralInFile(sourceFile, type, possiblePositions, references);
+            cancellationToken.throwIfCancellationRequested();
+            const possiblePositions = getPossibleSymbolReferencePositions(sourceFile, node.text, sourceFile.getStart(), sourceFile.getEnd(), cancellationToken);
+            getReferencesForStringLiteralInFile(sourceFile, node.text, possiblePositions, references);
         }
 
         return [{
@@ -1348,17 +1342,10 @@ namespace ts.FindAllReferences.Core {
             references
         }];
 
-        function getReferencesForStringLiteralInFile(sourceFile: SourceFile, searchType: Type, possiblePositions: number[], references: Push<NodeEntry>): void {
+        function getReferencesForStringLiteralInFile(sourceFile: SourceFile, searchText: string, possiblePositions: number[], references: Push<NodeEntry>): void {
             for (const position of possiblePositions) {
-                cancellationToken.throwIfCancellationRequested();
-
                 const node = getTouchingWord(sourceFile, position);
-                if (!node || node.kind !== SyntaxKind.StringLiteral) {
-                    return;
-                }
-
-                const type = getStringLiteralTypeForNode(<StringLiteral>node, checker);
-                if (type === searchType) {
+                if (node && node.kind === SyntaxKind.StringLiteral && (node as StringLiteral).text === searchText) {
                     references.push(nodeEntry(node, /*isInString*/true));
                 }
             }
diff --git a/src/services/rename.ts b/src/services/rename.ts
index 556283a44f4..bee530340bd 100644
--- a/src/services/rename.ts
+++ b/src/services/rename.ts
@@ -37,15 +37,12 @@ namespace ts.Rename {
             }
         }
         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);
+            if (isDefinedInLibraryFile(node)) {
+                return getRenameInfoError(Diagnostics.You_cannot_rename_elements_that_are_defined_in_the_standard_TypeScript_library);
             }
+
+            const displayName = stripQuotes((node as StringLiteral).text);
+            return getRenameInfoSuccess(displayName, displayName, ScriptElementKind.variableElement, ScriptElementKindModifier.none, node, sourceFile);
         }
     }
 
diff --git a/src/services/utilities.ts b/src/services/utilities.ts
index 95de9d3a503..9996c3cb160 100644
--- a/src/services/utilities.ts
+++ b/src/services/utilities.ts
@@ -364,15 +364,6 @@ namespace ts {
         }
     }
 
-    export function getStringLiteralTypeForNode(node: StringLiteral | LiteralTypeNode, typeChecker: TypeChecker): LiteralType {
-        const searchNode = node.parent.kind === SyntaxKind.LiteralType ? <LiteralTypeNode>node.parent : node;
-        const type = typeChecker.getTypeAtLocation(searchNode);
-        if (type && type.flags & TypeFlags.StringLiteral) {
-            return <LiteralType>type;
-        }
-        return undefined;
-    }
-
     export function isThis(node: Node): boolean {
         switch (node.kind) {
             case SyntaxKind.ThisKeyword: