feat(language-service): add services to support editors (#12987)

modules/@angular/language-service/src/ts_plugin.ts

@@ -0,0 +1,77 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import * as ts from 'typescript';
+
+import {createLanguageService} from './language_service';
+import {LanguageService, LanguageServiceHost} from './types';
+import {TypeScriptServiceHost} from './typescript_host';
+
+
+/** A plugin to TypeScript's langauge service that provide language services for
+ * templates in string literals.
+ *
+ * @experimental
+ */
+export class LanguageServicePlugin {
+  private ts: typeof ts;
+  private serviceHost: TypeScriptServiceHost;
+  private service: LanguageService;
+  private host: ts.LanguageServiceHost;
+
+  static 'extension-kind' = 'language-service';
+
+  constructor(config: {
+    ts: typeof ts; host: ts.LanguageServiceHost; service: ts.LanguageService;
+    registry?: ts.DocumentRegistry, args?: any
+  }) {
+    this.ts = config.ts;
+    this.host = config.host;
+    this.serviceHost = new TypeScriptServiceHost(this.ts, config.host, config.service);
+    this.service = createLanguageService(this.serviceHost);
+    this.serviceHost.setSite(this.service);
+  }
+
+  /**
+   * Augment the diagnostics reported by TypeScript with errors from the templates in string
+   * literals.
+   */
+  getSemanticDiagnosticsFilter(fileName: string, previous: ts.Diagnostic[]): ts.Diagnostic[] {
+    let errors = this.service.getDiagnostics(fileName);
+    if (errors && errors.length) {
+      let file = this.serviceHost.getSourceFile(fileName);
+      for (const error of errors) {
+        previous.push({
+          file,
+          start: error.span.start,
+          length: error.span.end - error.span.start,
+          messageText: error.message,
+          category: this.ts.DiagnosticCategory.Error,
+          code: 0
+        });
+      }
+    }
+    return previous;
+  }
+
+  /**
+   * Get completions for angular templates if one is at the given position.
+   */
+  getCompletionsAtPosition(fileName: string, position: number): ts.CompletionInfo {
+    let result = this.service.getCompletionsAt(fileName, position);
+    if (result) {
+      return {
+        isMemberCompletion: false,
+        isNewIdentifierLocation: false,
+        entries: result.map<ts.CompletionEntry>(
+            entry =>
+                ({name: entry.name, kind: entry.kind, kindModifiers: '', sortText: entry.sort}))
+      };
+    }
+  }
+}