Convert classes to factory functions

TypeScript is better at inferring types when using simple functions and
objects instead of classes. As a result many type annotations have now
been removed without impacting type safety.

Some other benefits are this can be minified better and private fields
are now truly private variables.

index.d.ts

@@ -57,6 +57,7 @@ declare module 'monaco-editor/esm/vs/editor/editor.api' {
 
     export interface LanguageServiceDefaults {
       readonly onDidChange: IEvent<LanguageServiceDefaults>;
+      readonly languageId: string;
       readonly diagnosticsOptions: DiagnosticsOptions;
       setDiagnosticsOptions: (options: DiagnosticsOptions) => void;
     }

src/languageFeatures.ts

@@ -11,7 +11,6 @@ import {
 import * as ls from 'vscode-languageserver-types';
 import { CustomFormatterOptions } from 'yaml-language-server/lib/esm/languageservice/yamlLanguageService';
 
-import { LanguageServiceDefaultsImpl } from './monaco.contribution';
 import { YAMLWorker } from './yamlWorker';
 
 export type WorkerAccessor = (...more: Uri[]) => PromiseLike<YAMLWorker>;
@@ -48,85 +47,22 @@ function toDiagnostics(resource: Uri, diag: ls.Diagnostic): editor.IMarkerData {
   };
 }
 
-export class DiagnosticsAdapter {
+export function createDiagnosticsAdapter(
-  private _disposables: IDisposable[] = [];
+  languageId: string,
-  private _listener: Record<string, IDisposable> = Object.create(null);
+  getWorker: WorkerAccessor,
+  defaults: languages.yaml.LanguageServiceDefaults,
+): IDisposable {
+  let disposables: IDisposable[] = [];
+  const listeners: Record<string, IDisposable> = Object.create(null);
 
-  constructor(
+  const resetSchema = (resource: Uri): void => {
-    private _languageId: string,
+    getWorker().then((worker) => {
-    private _worker: WorkerAccessor,
-    defaults: LanguageServiceDefaultsImpl,
-  ) {
-    const onModelAdd = (model: editor.IModel): void => {
-      const modeId = model.getModeId();
-      if (modeId !== this._languageId) {
-        return;
-      }
-
-      let handle: number;
-      this._listener[String(toString)] = model.onDidChangeContent(() => {
-        clearTimeout(handle);
-        handle = setTimeout(() => this._doValidate(model.uri, modeId), 500);
-      });
-
-      this._doValidate(model.uri, modeId);
-    };
-
-    const onModelRemoved = (model: editor.IModel): void => {
-      editor.setModelMarkers(model, this._languageId, []);
-      const uriStr = String(model.uri);
-      const listener = this._listener[uriStr];
-      if (listener) {
-        listener.dispose();
-        delete this._listener[uriStr];
-      }
-    };
-
-    this._disposables.push(
-      editor.onDidCreateModel(onModelAdd),
-      editor.onWillDisposeModel((model) => {
-        onModelRemoved(model);
-        this._resetSchema(model.uri);
-      }),
-      editor.onDidChangeModelLanguage((event) => {
-        onModelRemoved(event.model);
-        onModelAdd(event.model);
-        this._resetSchema(event.model.uri);
-      }),
-      defaults.onDidChange(() => {
-        editor.getModels().forEach((model) => {
-          if (model.getModeId() === this._languageId) {
-            onModelRemoved(model);
-            onModelAdd(model);
-          }
-        });
-      }),
-      {
-        dispose: () => {
-          editor.getModels().forEach(onModelRemoved);
-          for (const disposable of Object.values(this._listener)) {
-            disposable.dispose();
-          }
-        },
-      },
-    );
-
-    editor.getModels().forEach(onModelAdd);
-  }
-
-  dispose(): void {
-    this._disposables.forEach((d) => d && d.dispose());
-    this._disposables = [];
-  }
-
-  private _resetSchema(resource: Uri): void {
-    this._worker().then((worker) => {
       worker.resetSchema(String(resource));
     });
-  }
+  };
 
-  private _doValidate(resource: Uri, languageId: string): void {
+  const doValidate = (resource: Uri, languageId: string): void => {
-    this._worker(resource)
+    getWorker(resource)
       .then((worker) =>
         worker.doValidation(String(resource)).then((diagnostics) => {
           const markers = diagnostics.map((d) => toDiagnostics(resource, d));
@@ -139,7 +75,70 @@ export class DiagnosticsAdapter {
       .then(undefined, (err) => {
         console.error(err);
       });
-  }
+  };
+
+  const onModelAdd = (model: editor.IModel): void => {
+    const modeId = model.getModeId();
+    if (modeId !== languageId) {
+      return;
+    }
+
+    let handle: number;
+    listeners[String(toString)] = model.onDidChangeContent(() => {
+      clearTimeout(handle);
+      handle = setTimeout(() => doValidate(model.uri, modeId), 500);
+    });
+
+    doValidate(model.uri, modeId);
+  };
+
+  const onModelRemoved = (model: editor.IModel): void => {
+    editor.setModelMarkers(model, languageId, []);
+    const uriStr = String(model.uri);
+    const listener = listeners[uriStr];
+    if (listener) {
+      listener.dispose();
+      delete listeners[uriStr];
+    }
+  };
+
+  disposables.push(
+    editor.onDidCreateModel(onModelAdd),
+    editor.onWillDisposeModel((model) => {
+      onModelRemoved(model);
+      resetSchema(model.uri);
+    }),
+    editor.onDidChangeModelLanguage((event) => {
+      onModelRemoved(event.model);
+      onModelAdd(event.model);
+      resetSchema(event.model.uri);
+    }),
+    defaults.onDidChange(() => {
+      editor.getModels().forEach((model) => {
+        if (model.getModeId() === languageId) {
+          onModelRemoved(model);
+          onModelAdd(model);
+        }
+      });
+    }),
+    {
+      dispose: () => {
+        editor.getModels().forEach(onModelRemoved);
+        for (const disposable of Object.values(listeners)) {
+          disposable.dispose();
+        }
+      },
+    },
+  );
+
+  editor.getModels().forEach(onModelAdd);
+
+  return {
+    dispose() {
+      disposables.forEach((d) => d && d.dispose());
+      disposables = [];
+    },
+  };
 }
 
 // --- completion ------
@@ -218,64 +217,66 @@ function toTextEdit(textEdit: ls.TextEdit): editor.ISingleEditOperation {
   };
 }
 
-export class CompletionAdapter implements languages.CompletionItemProvider {
+export function createCompletionItemProvider(
-  triggetCharacters = [' ', ':'];
+  getWorker: WorkerAccessor,
+): languages.CompletionItemProvider {
+  return {
+    triggerCharacters: [' ', ':'],
 
-  constructor(private _worker: WorkerAccessor) {}
+    provideCompletionItems(
+      model: editor.IReadOnlyModel,
+      position: Position,
+    ): PromiseLike<languages.CompletionList> {
+      const resource = model.uri;
 
-  provideCompletionItems(
+      return getWorker(resource)
-    model: editor.IReadOnlyModel,
+        .then((worker) => worker.doComplete(String(resource), fromPosition(position)))
-    position: Position,
+        .then((info) => {
-  ): PromiseLike<languages.CompletionList> {
+          if (!info) {
-    const resource = model.uri;
+            return;
+          }
 
-    return this._worker(resource)
+          const wordInfo = model.getWordUntilPosition(position);
-      .then((worker) => worker.doComplete(String(resource), fromPosition(position)))
+          const wordRange = new Range(
-      .then((info) => {
+            position.lineNumber,
-        if (!info) {
+            wordInfo.startColumn,
-          return;
+            position.lineNumber,
-        }
+            wordInfo.endColumn,
+          );
 
-        const wordInfo = model.getWordUntilPosition(position);
+          const items = info.items.map((entry) => {
-        const wordRange = new Range(
+            const item: languages.CompletionItem = {
-          position.lineNumber,
+              label: entry.label,
-          wordInfo.startColumn,
+              insertText: entry.insertText || entry.label,
-          position.lineNumber,
+              sortText: entry.sortText,
-          wordInfo.endColumn,
+              filterText: entry.filterText,
-        );
+              documentation: entry.documentation,
+              detail: entry.detail,
+              kind: toCompletionItemKind(entry.kind),
+              range: wordRange,
+            };
+            if (entry.textEdit) {
+              item.range = toRange(
+                'range' in entry.textEdit ? entry.textEdit.range : entry.textEdit.replace,
+              );
+              item.insertText = entry.textEdit.newText;
+            }
+            if (entry.additionalTextEdits) {
+              item.additionalTextEdits = entry.additionalTextEdits.map(toTextEdit);
+            }
+            if (entry.insertTextFormat === ls.InsertTextFormat.Snippet) {
+              item.insertTextRules = languages.CompletionItemInsertTextRule.InsertAsSnippet;
+            }
+            return item;
+          });
 
-        const items: languages.CompletionItem[] = info.items.map((entry) => {
+          return {
-          const item: languages.CompletionItem = {
+            isIncomplete: info.isIncomplete,
-            label: entry.label,
+            suggestions: items,
-            insertText: entry.insertText || entry.label,
-            sortText: entry.sortText,
-            filterText: entry.filterText,
-            documentation: entry.documentation,
-            detail: entry.detail,
-            kind: toCompletionItemKind(entry.kind),
-            range: wordRange,
           };
-          if (entry.textEdit) {
-            item.range = toRange(
-              'range' in entry.textEdit ? entry.textEdit.range : entry.textEdit.replace,
-            );
-            item.insertText = entry.textEdit.newText;
-          }
-          if (entry.additionalTextEdits) {
-            item.additionalTextEdits = entry.additionalTextEdits.map(toTextEdit);
-          }
-          if (entry.insertTextFormat === ls.InsertTextFormat.Snippet) {
-            item.insertTextRules = languages.CompletionItemInsertTextRule.InsertAsSnippet;
-          }
-          return item;
         });
-
+    },
-        return {
+  };
-          isIncomplete: info.isIncomplete,
-          suggestions: items,
-        };
-      });
-  }
 }
 
 function isMarkupContent(thing: unknown): thing is ls.MarkupContent {
@@ -316,24 +317,24 @@ function toMarkedStringArray(
 
 // --- hover ------
 
-export class HoverAdapter implements languages.HoverProvider {
+export function createHoverProvider(getWorker: WorkerAccessor): languages.HoverProvider {
-  constructor(private _worker: WorkerAccessor) {}
+  return {
+    provideHover(model, position) {
+      const resource = model.uri;
 
-  provideHover(model: editor.IReadOnlyModel, position: Position): PromiseLike<languages.Hover> {
+      return getWorker(resource)
-    const resource = model.uri;
+        .then((worker) => worker.doHover(String(resource), fromPosition(position)))
-
+        .then((info) => {
-    return this._worker(resource)
+          if (!info) {
-      .then((worker) => worker.doHover(String(resource), fromPosition(position)))
+            return;
-      .then((info) => {
+          }
-        if (!info) {
+          return {
-          return;
+            range: toRange(info.range),
-        }
+            contents: toMarkedStringArray(info.contents),
-        return {
+          } as languages.Hover;
-          range: toRange(info.range),
+        });
-          contents: toMarkedStringArray(info.contents),
+    },
-        } as languages.Hover;
+  };
-      });
-  }
 }
 
 // --- document symbols ------
@@ -395,21 +396,23 @@ function toDocumentSymbol(item: ls.DocumentSymbol): languages.DocumentSymbol {
   };
 }
 
-export class DocumentSymbolAdapter implements languages.DocumentSymbolProvider {
+export function createDocumentSymbolProvider(
-  constructor(private _worker: WorkerAccessor) {}
+  getWorker: WorkerAccessor,
+): languages.DocumentSymbolProvider {
+  return {
+    provideDocumentSymbols(model) {
+      const resource = model.uri;
 
-  provideDocumentSymbols(model: editor.IReadOnlyModel): PromiseLike<languages.DocumentSymbol[]> {
+      return getWorker(resource)
-    const resource = model.uri;
+        .then((worker) => worker.findDocumentSymbols(String(resource)))
-
+        .then((items) => {
-    return this._worker(resource)
+          if (!items) {
-      .then((worker) => worker.findDocumentSymbols(String(resource)))
+            return;
-      .then((items) => {
+          }
-        if (!items) {
+          return items.map((item) => toDocumentSymbol(item));
-          return;
+        });
-        }
+    },
-        return items.map((item) => toDocumentSymbol(item));
+  };
-      });
-  }
 }
 
 function fromFormattingOptions(
@@ -422,22 +425,21 @@ function fromFormattingOptions(
   };
 }
 
-export class DocumentFormattingEditProvider implements languages.DocumentFormattingEditProvider {
+export function createDocumentFormattingEditProvider(
-  constructor(private _worker: WorkerAccessor) {}
+  getWorker: WorkerAccessor,
+): languages.DocumentFormattingEditProvider {
+  return {
+    provideDocumentFormattingEdits(model, options) {
+      const resource = model.uri;
 
-  provideDocumentFormattingEdits(
+      return getWorker(resource).then((worker) =>
-    model: editor.IReadOnlyModel,
+        worker.format(String(resource), fromFormattingOptions(options)).then((edits) => {
-    options: languages.FormattingOptions,
+          if (!edits || edits.length === 0) {
-  ): PromiseLike<editor.ISingleEditOperation[]> {
+            return;
-    const resource = model.uri;
+          }
-
+          return edits.map(toTextEdit);
-    return this._worker(resource).then((worker) =>
+        }),
-      worker.format(String(resource), fromFormattingOptions(options)).then((edits) => {
+      );
-        if (!edits || edits.length === 0) {
+    },
-          return;
+  };
-        }
-        return edits.map(toTextEdit);
-      }),
-    );
-  }
 }

src/monaco.contribution.ts

@@ -1,35 +1,36 @@
-import { Emitter, IEvent, languages } from 'monaco-editor/esm/vs/editor/editor.api';
+import { Emitter, languages } from 'monaco-editor/esm/vs/editor/editor.api';
 
 import { setupMode } from './yamlMode';
 
 // --- YAML configuration and defaults ---------
 
-export class LanguageServiceDefaultsImpl implements languages.yaml.LanguageServiceDefaults {
+export function createLanguageServiceDefaults(
-  private _onDidChange = new Emitter<languages.yaml.LanguageServiceDefaults>();
+  languageId: string,
-  private _diagnosticsOptions: languages.yaml.DiagnosticsOptions;
+  initialDiagnosticsOptions: languages.yaml.DiagnosticsOptions,
-  private _languageId: string;
+): languages.yaml.LanguageServiceDefaults {
+  const onDidChange = new Emitter<languages.yaml.LanguageServiceDefaults>();
+  let diagnosticsOptions = initialDiagnosticsOptions;
 
-  constructor(languageId: string, diagnosticsOptions: languages.yaml.DiagnosticsOptions) {
+  const languageServiceDefaults: languages.yaml.LanguageServiceDefaults = {
-    this._languageId = languageId;
+    get onDidChange() {
-    this.setDiagnosticsOptions(diagnosticsOptions);
+      return onDidChange.event;
-  }
+    },
 
-  get onDidChange(): IEvent<languages.yaml.LanguageServiceDefaults> {
+    get languageId() {
-    return this._onDidChange.event;
+      return languageId;
-  }
+    },
 
-  get languageId(): string {
+    get diagnosticsOptions() {
-    return this._languageId;
+      return diagnosticsOptions;
-  }
+    },
 
-  get diagnosticsOptions(): languages.yaml.DiagnosticsOptions {
+    setDiagnosticsOptions(options) {
-    return this._diagnosticsOptions;
+      diagnosticsOptions = options || {};
-  }
+      onDidChange.fire(languageServiceDefaults);
+    },
+  };
 
-  setDiagnosticsOptions(options: languages.yaml.DiagnosticsOptions): void {
+  return languageServiceDefaults;
-    this._diagnosticsOptions = options || Object.create(null);
-    this._onDidChange.fire(this);
-  }
 }
 
 const diagnosticDefault: languages.yaml.DiagnosticsOptions = {
@@ -38,7 +39,7 @@ const diagnosticDefault: languages.yaml.DiagnosticsOptions = {
   enableSchemaRequest: false,
 };
 
-const yamlDefaults = new LanguageServiceDefaultsImpl('yaml', diagnosticDefault);
+const yamlDefaults = createLanguageServiceDefaults('yaml', diagnosticDefault);
 
 // Export API
 function createAPI(): typeof languages.yaml {

src/workerManager.ts

@@ -1,85 +1,82 @@
-import { editor, IDisposable, Uri } from 'monaco-editor/esm/vs/editor/editor.api';
+import { editor, IDisposable, languages, Uri } from 'monaco-editor/esm/vs/editor/editor.api';
 
-import { LanguageServiceDefaultsImpl } from './monaco.contribution';
 import { YAMLWorker } from './yamlWorker';
 
+export interface WorkerManager extends IDisposable {
+  getLanguageServiceWorker: (...resources: Uri[]) => Promise<YAMLWorker>;
+}
+
 // 2min
 const STOP_WHEN_IDLE_FOR = 2 * 60 * 1000;
 
-export class WorkerManager {
+export function createWorkerManager(
-  private _defaults: LanguageServiceDefaultsImpl;
+  defaults: languages.yaml.LanguageServiceDefaults,
-  private _idleCheckInterval: number;
+): WorkerManager {
-  private _lastUsedTime: number;
+  let worker: editor.MonacoWebWorker<YAMLWorker>;
-  private _configChangeListener: IDisposable;
+  let client: Promise<YAMLWorker>;
+  let lastUsedTime = 0;
 
-  private _worker: editor.MonacoWebWorker<YAMLWorker>;
+  const stopWorker = (): void => {
-  private _client: Promise<YAMLWorker>;
+    if (worker) {
-
+      worker.dispose();
-  constructor(defaults: LanguageServiceDefaultsImpl) {
+      worker = null;
-    this._defaults = defaults;
-    this._worker = null;
-    this._idleCheckInterval = setInterval(() => this._checkIfIdle(), 30 * 1000);
-    this._lastUsedTime = 0;
-    this._configChangeListener = this._defaults.onDidChange(() => this._stopWorker());
-  }
-
-  dispose(): void {
-    clearInterval(this._idleCheckInterval);
-    this._configChangeListener.dispose();
-    this._stopWorker();
-  }
-
-  getLanguageServiceWorker(...resources: Uri[]): Promise<YAMLWorker> {
-    let _client: YAMLWorker;
-    return this._getClient()
-      .then((client) => {
-        _client = client;
-      })
-      .then(() => this._worker.withSyncedResources(resources))
-      .then(() => _client);
-  }
-
-  private _stopWorker(): void {
-    if (this._worker) {
-      this._worker.dispose();
-      this._worker = null;
     }
-    this._client = null;
+    client = null;
-  }
+  };
 
-  private _checkIfIdle(): void {
+  const idleCheckInterval = setInterval(() => {
-    if (!this._worker) {
+    if (!worker) {
       return;
     }
-    const timePassedSinceLastUsed = Date.now() - this._lastUsedTime;
+    const timePassedSinceLastUsed = Date.now() - lastUsedTime;
     if (timePassedSinceLastUsed > STOP_WHEN_IDLE_FOR) {
-      this._stopWorker();
+      stopWorker();
     }
-  }
+  }, 30 * 1000);
 
-  private _getClient(): Promise<YAMLWorker> {
+  const configChangeListener = defaults.onDidChange(() => stopWorker());
-    this._lastUsedTime = Date.now();
 
-    if (!this._client) {
+  const getClient = (): Promise<YAMLWorker> => {
-      this._worker = editor.createWebWorker<YAMLWorker>({
+    lastUsedTime = Date.now();
+
+    if (!client) {
+      worker = editor.createWebWorker<YAMLWorker>({
         // Module that exports the create() method and returns a `YAMLWorker` instance
         moduleId: 'vs/language/yaml/yamlWorker',
 
-        label: this._defaults.languageId,
+        label: defaults.languageId,
 
         // Passed in to the create() method
         createData: {
-          languageSettings: this._defaults.diagnosticsOptions,
+          languageSettings: defaults.diagnosticsOptions,
-          languageId: this._defaults.languageId,
+          languageId: defaults.languageId,
-          enableSchemaRequest: this._defaults.diagnosticsOptions.enableSchemaRequest,
+          enableSchemaRequest: defaults.diagnosticsOptions.enableSchemaRequest,
-          prefix: this._defaults.diagnosticsOptions.prefix,
+          prefix: defaults.diagnosticsOptions.prefix,
-          isKubernetes: this._defaults.diagnosticsOptions.isKubernetes,
+          isKubernetes: defaults.diagnosticsOptions.isKubernetes,
         },
       });
 
-      this._client = this._worker.getProxy();
+      client = worker.getProxy();
     }
 
-    return this._client;
+    return client;
-  }
+  };
+
+  return {
+    dispose() {
+      clearInterval(idleCheckInterval);
+      configChangeListener.dispose();
+      stopWorker();
+    },
+
+    getLanguageServiceWorker(...resources) {
+      let _client: YAMLWorker;
+      return getClient()
+        .then((client) => {
+          _client = client;
+        })
+        .then(() => worker.withSyncedResources(resources))
+        .then(() => _client);
+    },
+  };
 }

src/yaml.worker.ts

@@ -1,8 +1,7 @@
-import * as worker from 'monaco-editor/esm/vs/editor/editor.worker';
+import { initialize } from 'monaco-editor/esm/vs/editor/editor.worker';
 
-import { YAMLWorker } from './yamlWorker';
+import { createYAMLWorker } from './yamlWorker';
 
 self.onmessage = () => {
-  // Ignore the first message
+  initialize((ctx, createData) => Object.create(createYAMLWorker(ctx, createData)));
-  worker.initialize((ctx, createData) => new YAMLWorker(ctx, createData));
 };

src/yamlMode.ts

@@ -1,8 +1,14 @@
 import { IDisposable, languages, Uri } from 'monaco-editor/esm/vs/editor/editor.api';
 
-import * as languageFeatures from './languageFeatures';
+import {
-import { LanguageServiceDefaultsImpl } from './monaco.contribution';
+  createCompletionItemProvider,
-import { WorkerManager } from './workerManager';
+  createDiagnosticsAdapter,
+  createDocumentFormattingEditProvider,
+  createDocumentSymbolProvider,
+  createHoverProvider,
+  WorkerAccessor,
+} from './languageFeatures';
+import { createWorkerManager } from './workerManager';
 import { YAMLWorker } from './yamlWorker';
 
 const richEditConfiguration: languages.LanguageConfiguration = {
@@ -37,32 +43,26 @@ const richEditConfiguration: languages.LanguageConfiguration = {
   ],
 };
 
-export function setupMode(defaults: LanguageServiceDefaultsImpl): void {
+export function setupMode(defaults: languages.yaml.LanguageServiceDefaults): void {
   const disposables: IDisposable[] = [];
 
-  const client = new WorkerManager(defaults);
+  const client = createWorkerManager(defaults);
   disposables.push(client);
 
-  const worker: languageFeatures.WorkerAccessor = (...uris: Uri[]): Promise<YAMLWorker> =>
+  const worker: WorkerAccessor = (...uris: Uri[]): Promise<YAMLWorker> =>
     client.getLanguageServiceWorker(...uris);
 
   const { languageId } = defaults;
 
   disposables.push(
-    languages.registerCompletionItemProvider(
+    languages.registerCompletionItemProvider(languageId, createCompletionItemProvider(worker)),
-      languageId,
+    languages.registerHoverProvider(languageId, createHoverProvider(worker)),
-      new languageFeatures.CompletionAdapter(worker),
+    languages.registerDocumentSymbolProvider(languageId, createDocumentSymbolProvider(worker)),
-    ),
-    languages.registerHoverProvider(languageId, new languageFeatures.HoverAdapter(worker)),
-    languages.registerDocumentSymbolProvider(
-      languageId,
-      new languageFeatures.DocumentSymbolAdapter(worker),
-    ),
     languages.registerDocumentFormattingEditProvider(
       languageId,
-      new languageFeatures.DocumentFormattingEditProvider(worker),
+      createDocumentFormattingEditProvider(worker),
     ),
-    new languageFeatures.DiagnosticsAdapter(languageId, worker, defaults),
+    createDiagnosticsAdapter(languageId, worker, defaults),
     languages.setLanguageConfiguration(languageId, richEditConfiguration),
   );
 }

src/yamlWorker.ts

@@ -1,6 +1,10 @@
 import { worker } from 'monaco-editor/esm/vs/editor/editor.api';
 import * as ls from 'vscode-languageserver-types';
-import * as yamlService from 'yaml-language-server/lib/esm/languageservice/yamlLanguageService';
+import {
+  CustomFormatterOptions,
+  getLanguageService,
+  LanguageSettings,
+} from 'yaml-language-server/lib/esm/languageservice/yamlLanguageService';
 
 let defaultSchemaRequestService: (url: string) => PromiseLike<string>;
 
@@ -8,90 +12,96 @@ if (typeof fetch !== 'undefined') {
   defaultSchemaRequestService = (url) => fetch(url).then((response) => response.text());
 }
 
-export class YAMLWorker {
+export interface YAMLWorker {
-  private _ctx: worker.IWorkerContext;
+  doValidation: (uri: string) => PromiseLike<ls.Diagnostic[]>;
-  private _languageService: yamlService.LanguageService;
-  private _languageSettings: yamlService.LanguageSettings;
-  private _languageId: string;
-  private _isKubernetes: boolean;
 
-  constructor(ctx: worker.IWorkerContext, createData: ICreateData) {
+  doComplete: (uri: string, position: ls.Position) => PromiseLike<ls.CompletionList>;
-    const prefix = createData.prefix || '';
-    const service = (url: string): PromiseLike<string> =>
-      defaultSchemaRequestService(`${prefix}${url}`);
-    this._ctx = ctx;
-    this._languageSettings = createData.languageSettings;
-    this._languageId = createData.languageId;
-    this._languageService = yamlService.getLanguageService(
-      createData.enableSchemaRequest && service,
-      null,
-      [],
-    );
-    this._isKubernetes = createData.isKubernetes || false;
-    this._languageService.configure({
-      ...this._languageSettings,
-      hover: true,
-      isKubernetes: this._isKubernetes,
-    });
-  }
 
-  doValidation(uri: string): PromiseLike<ls.Diagnostic[]> {
+  doResolve: (item: ls.CompletionItem) => PromiseLike<ls.CompletionItem>;
-    const document = this._getTextDocument(uri);
-    if (document) {
-      return this._languageService.doValidation(document, this._isKubernetes);
-    }
-    return Promise.resolve([]);
-  }
 
-  doComplete(uri: string, position: ls.Position): PromiseLike<ls.CompletionList> {
+  doHover: (uri: string, position: ls.Position) => PromiseLike<ls.Hover>;
-    const document = this._getTextDocument(uri);
-    return this._languageService.doComplete(document, position, this._isKubernetes);
-  }
 
-  doResolve(item: ls.CompletionItem): PromiseLike<ls.CompletionItem> {
+  format: (uri: string, options: CustomFormatterOptions) => PromiseLike<ls.TextEdit[]>;
-    return this._languageService.doResolve(item);
-  }
 
-  doHover(uri: string, position: ls.Position): PromiseLike<ls.Hover> {
+  resetSchema: (uri: string) => PromiseLike<boolean>;
-    const document = this._getTextDocument(uri);
-    return this._languageService.doHover(document, position);
-  }
 
-  format(uri: string, options: yamlService.CustomFormatterOptions): PromiseLike<ls.TextEdit[]> {
+  findDocumentSymbols: (uri: string) => PromiseLike<ls.DocumentSymbol[]>;
-    const document = this._getTextDocument(uri);
+}
-    const textEdits = this._languageService.doFormat(document, options);
-    return Promise.resolve(textEdits);
-  }
 
-  resetSchema(uri: string): PromiseLike<boolean> {
+export function createYAMLWorker(
-    return Promise.resolve(this._languageService.resetSchema(uri));
+  ctx: worker.IWorkerContext,
-  }
+  {
+    enableSchemaRequest,
+    isKubernetes = false,
+    languageId,
+    languageSettings,
+    prefix = '',
+  }: ICreateData,
+): YAMLWorker {
+  const service = (url: string): PromiseLike<string> =>
+    defaultSchemaRequestService(`${prefix}${url}`);
+  const languageService = getLanguageService(enableSchemaRequest && service, null, []);
+  languageService.configure({
+    ...languageSettings,
+    hover: true,
+    isKubernetes,
+  });
 
-  findDocumentSymbols(uri: string): PromiseLike<ls.DocumentSymbol[]> {
+  const getTextDocument = (uri: string): ls.TextDocument => {
-    const document = this._getTextDocument(uri);
+    const models = ctx.getMirrorModels();
-    const symbols = this._languageService.findDocumentSymbols2(document);
-    return Promise.resolve(symbols);
-  }
-
-  private _getTextDocument(uri: string): ls.TextDocument {
-    const models = this._ctx.getMirrorModels();
     for (const model of models) {
       if (String(model.uri) === uri) {
-        return ls.TextDocument.create(uri, this._languageId, model.version, model.getValue());
+        return ls.TextDocument.create(uri, languageId, model.version, model.getValue());
       }
     }
     return null;
-  }
+  };
+
+  return {
+    doValidation(uri) {
+      const document = getTextDocument(uri);
+      if (document) {
+        return languageService.doValidation(document, isKubernetes);
+      }
+      return Promise.resolve([]);
+    },
+
+    doComplete(uri, position) {
+      const document = getTextDocument(uri);
+      return languageService.doComplete(document, position, isKubernetes);
+    },
+
+    doResolve(item) {
+      return languageService.doResolve(item);
+    },
+
+    doHover(uri, position) {
+      const document = getTextDocument(uri);
+      return languageService.doHover(document, position);
+    },
+
+    format(uri, options) {
+      const document = getTextDocument(uri);
+      const textEdits = languageService.doFormat(document, options);
+      return Promise.resolve(textEdits);
+    },
+
+    resetSchema(uri) {
+      return Promise.resolve(languageService.resetSchema(uri));
+    },
+
+    findDocumentSymbols(uri) {
+      const document = getTextDocument(uri);
+      const symbols = languageService.findDocumentSymbols2(document);
+      return Promise.resolve(symbols);
+    },
+  };
 }
 
 export interface ICreateData {
   languageId: string;
-  languageSettings: yamlService.LanguageSettings;
+  languageSettings: LanguageSettings;
   enableSchemaRequest: boolean;
   prefix?: string;
   isKubernetes?: boolean;
 }
-
-export function create(ctx: worker.IWorkerContext, createData: ICreateData): YAMLWorker {
-  return new YAMLWorker(ctx, createData);
-}