Allow singleline string writer to be recursively used (microsoft#18297)

weswigham · web-flow · commit 5c779b1edbc1 · 2017-09-06T21:56:16.000-07:00
* Allow singleline string writer to be recursively used

* Add unit test exposing issue

* Fix lints
diff --git a/Jakefile.js b/Jakefile.js
@@ -143,6 +143,7 @@ var harnessSources = harnessCoreSources.concat([
     "customTransforms.ts",
     "programMissingFiles.ts",
     "symbolWalker.ts",
+    "languageService.ts",
 ].map(function (f) {
     return path.join(unittestsDirectory, f);
 })).concat([
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
@@ -32,7 +32,6 @@ namespace ts {
     }
 
     const stringWriter = createSingleLineStringWriter();
-    let stringWriterAcquired = false;
 
     function createSingleLineStringWriter(): StringSymbolWriter {
         let str = "";
@@ -62,15 +61,14 @@ namespace ts {
     }
 
     export function usingSingleLineStringWriter(action: (writer: StringSymbolWriter) => void): string {
+        const oldString = stringWriter.string();
         try {
-            Debug.assert(!stringWriterAcquired);
-            stringWriterAcquired = true;
             action(stringWriter);
             return stringWriter.string();
         }
         finally {
             stringWriter.clear();
-            stringWriterAcquired = false;
+            stringWriter.writeKeyword(oldString);
         }
     }
 
diff --git a/src/harness/tsconfig.json b/src/harness/tsconfig.json
@@ -128,6 +128,7 @@
         "./unittests/extractMethods.ts",
         "./unittests/textChanges.ts",
         "./unittests/telemetry.ts",
+        "./unittests/languageService.ts",
         "./unittests/programMissingFiles.ts"
     ]
 }
diff --git a/src/harness/unittests/languageService.ts b/src/harness/unittests/languageService.ts
@@ -0,0 +1,49 @@
+/// <reference path="..\harness.ts" />
+
+namespace ts {
+    describe("languageService", () => {
+        const files: {[index: string]: string} = {
+            "foo.ts": `import Vue from "./vue";
+import Component from "./vue-class-component";
+import { vueTemplateHtml } from "./variables";
+
+@Component({
+    template: vueTemplateHtml,
+})
+class Carousel<T> extends Vue {
+}`,
+            "variables.ts": `export const vueTemplateHtml = \`<div></div>\`;`,
+            "vue.d.ts": `export namespace Vue { export type Config = { template: string }; }`,
+            "vue-class-component.d.ts": `import Vue from "./vue";
+export function Component(x: Config): any;`
+};
+        it("should be able to create a language service which can respond to deinition requests without throwing", () => {
+            const languageService = ts.createLanguageService({
+                getCompilationSettings() {
+                    return {};
+                },
+                getScriptFileNames() {
+                    return ["foo.ts", "variables.ts", "vue.d.ts", "vue-class-component.d.ts"];
+                },
+                getScriptVersion(_fileName) {
+                    return "";
+                },
+                getScriptSnapshot(fileName) {
+                    if (fileName === ".ts") {
+                        return ts.ScriptSnapshot.fromString("");
+                    }
+                    return ts.ScriptSnapshot.fromString(files[fileName] || "");
+                },
+                getCurrentDirectory: () => ".",
+                getDefaultLibFileName(options) {
+                    return ts.getDefaultLibFilePath(options);
+                },
+                fileExists: noop as any,
+                readFile: noop as any,
+                readDirectory: noop as any,
+            });
+            const definitions = languageService.getDefinitionAtPosition("foo.ts", 160); // 160 is the latter `vueTemplateHtml` position
+            expect(definitions).to.exist;
+        });
+    });
+}

Original file line number	Diff line number	Diff line change
`@@ -32,7 +32,6 @@ namespace ts {`
`32`	`32`	`}`
`33`	`33`
`34`	`34`	`const stringWriter = createSingleLineStringWriter();`
`35`		`- let stringWriterAcquired = false;`
`36`	`35`
`37`	`36`	`function createSingleLineStringWriter(): StringSymbolWriter {`
`38`	`37`	`let str = "";`
`@@ -62,15 +61,14 @@ namespace ts {`
`62`	`61`	`}`
`63`	`62`
`64`	`63`	`export function usingSingleLineStringWriter(action: (writer: StringSymbolWriter) => void): string {`
	`64`	`+ const oldString = stringWriter.string();`
`65`	`65`	`try {`
`66`		`- Debug.assert(!stringWriterAcquired);`
`67`		`- stringWriterAcquired = true;`
`68`	`66`	`action(stringWriter);`
`69`	`67`	`return stringWriter.string();`
`70`	`68`	`}`
`71`	`69`	`finally {`
`72`	`70`	`stringWriter.clear();`
`73`		`- stringWriterAcquired = false;`
	`71`	`+ stringWriter.writeKeyword(oldString);`
`74`	`72`	`}`
`75`	`73`	`}`
`76`	`74`
Original file line number	Diff line number	Diff line change
`@@ -128,6 +128,7 @@`
`128`	`128`	`"./unittests/extractMethods.ts",`
`129`	`129`	`"./unittests/textChanges.ts",`
`130`	`130`	`"./unittests/telemetry.ts",`
	`131`	`+ "./unittests/languageService.ts",`
`131`	`132`	`"./unittests/programMissingFiles.ts"`
`132`	`133`	`]`
`133`	`134`	`}`