Add pending widget methods, reduce breakage

Signed-off-by: Colin Grant <colin.grant@ericsson.com>

packages/core/src/browser/widget-manager.ts

@@ -165,16 +165,30 @@ export class WidgetManager {
         return undefined;
     }
 
+    /**
+     * Try to get the existing widget for the given description.
+     * @param factoryId The widget factory id.
+     * @param options The widget factory specific information.
+     *
+     * @returns A promise that resolves to the widget, if any exists. The promise may be pending, so be cautious when assuming that it will not reject.
+     */
+    tryGetPendingWidget<T extends Widget>(factoryId: string, options?: any): MaybePromise<T> | undefined {
+        const key = this.toKey({ factoryId, options });
+        return this.doGetWidget(key);
+    }
+
     /**
      * Get the widget for the given description.
      * @param factoryId The widget factory id.
      * @param options The widget factory specific information.
      *
      * @returns a promise resolving to the widget if available, else `undefined`.
      */
-    getWidget<T extends Widget>(factoryId: string, options?: any): MaybePromise<T> | undefined {
+    async getWidget<T extends Widget>(factoryId: string, options?: any): Promise<T | undefined> {
         const key = this.toKey({ factoryId, options });
-        return this.doGetWidget<T>(key);
+        const pendingWidget = this.doGetWidget<T>(key);
+        const widget = pendingWidget && await pendingWidget;
+        return widget;
     }
 
     protected doGetWidget<T extends Widget>(key: string): MaybePromise<T> | undefined {

packages/core/src/browser/widget-open-handler.ts

@@ -111,7 +111,7 @@ export abstract class WidgetOpenHandler<W extends BaseWidget> implements OpenHan
      *
      * @returns a promise that resolves to the existing widget or `undefined` if no widget for the given uri exists.
      */
-    getByUri(uri: URI): MaybePromise<W> | undefined {
+    getByUri(uri: URI): Promise<W | undefined> {
         return this.getWidget(uri);
     }
 
@@ -136,7 +136,12 @@ export abstract class WidgetOpenHandler<W extends BaseWidget> implements OpenHan
         return this.widgetManager.getWidgets(this.id) as W[];
     }
 
-    protected getWidget(uri: URI, options?: WidgetOpenerOptions): MaybePromise<W> | undefined {
+    protected tryGetPendingWidget(uri: URI, options?: WidgetOpenerOptions): MaybePromise<W> | undefined {
+        const factoryOptions = this.createWidgetOptions(uri, options);
+        return this.widgetManager.tryGetPendingWidget(this.id, factoryOptions);
+    }
+
+    protected getWidget(uri: URI, options?: WidgetOpenerOptions): Promise<W | undefined> {
         const widgetOptions = this.createWidgetOptions(uri, options);
         return this.widgetManager.getWidget<W>(this.id, widgetOptions);
     }

packages/editor-preview/src/browser/editor-preview-frontend-module.ts

@@ -1,5 +1,5 @@
 /********************************************************************************
- * Copyright (C) 2018 Google and others.
+ * Copyright (C) 2018-2021 Google and others.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v. 2.0 which is available at

packages/editor-preview/src/browser/editor-preview-manager.ts

@@ -98,12 +98,16 @@ export class EditorPreviewManager extends EditorManager {
         this.toDisposeOnPreviewChange.push(widget.onDidDispose(() => this.toDisposeOnPreviewChange.dispose()));
     }
 
-    protected getWidget(uri: URI, options?: EditorOpenerOptions): MaybePromise<EditorWidget> | undefined {
-        return super.getWidget(uri, { ...options, preview: true }) ?? super.getWidget(uri, { ...options, preview: false });
+    protected tryGetPendingWidget(uri: URI, options?: EditorOpenerOptions): MaybePromise<EditorWidget> | undefined {
+        return super.tryGetPendingWidget(uri, { ...options, preview: true }) ?? super.tryGetPendingWidget(uri, { ...options, preview: false });
+    }
+
+    protected async getWidget(uri: URI, options?: EditorOpenerOptions): Promise<EditorWidget | undefined> {
+        return (await super.getWidget(uri, { ...options, preview: true })) ?? super.getWidget(uri, { ...options, preview: false });
     }
 
     protected async getOrCreateWidget(uri: URI, options?: EditorOpenerOptions): Promise<EditorWidget> {
-        return this.getWidget(uri, options) ?? super.getOrCreateWidget(uri, options);
+        return this.tryGetPendingWidget(uri, options) ?? super.getOrCreateWidget(uri, options);
     }
 
     protected createWidgetOptions(uri: URI, options?: EditorOpenerOptions): EditorPreviewOptions {

packages/editor/src/browser/editor-manager.ts

@@ -82,16 +82,16 @@ export class EditorManager extends NavigatableWidgetOpenHandler<EditorWidget> {
         this.updateCurrentEditor();
     }
 
-    getByUri(uri: URI, options?: EditorOpenerOptions): MaybePromise<EditorWidget> | undefined {
+    getByUri(uri: URI, options?: EditorOpenerOptions): Promise<EditorWidget | undefined> {
         return this.getWidget(uri, options);
     }
 
     getOrCreateByUri(uri: URI, options?: EditorOpenerOptions): Promise<EditorWidget> {
         return this.getOrCreateWidget(uri, options);
     }
 
-    protected getWidget(uri: URI, options?: EditorOpenerOptions): MaybePromise<EditorWidget> | undefined {
-        const editorPromise = super.getWidget(uri, options);
+    protected tryGetPendingWidget(uri: URI, options?: EditorOpenerOptions): MaybePromise<EditorWidget> | undefined {
+        const editorPromise = super.tryGetPendingWidget(uri, options);
         if (editorPromise) {
             // Reveal selection before attachment to manage nav stack. (https://github.com/eclipse-theia/theia/issues/8955)
             if (!(editorPromise instanceof Widget)) {
@@ -103,6 +103,15 @@ export class EditorManager extends NavigatableWidgetOpenHandler<EditorWidget> {
         return editorPromise;
     }
 
+    protected async getWidget(uri: URI, options?: EditorOpenerOptions): Promise<EditorWidget | undefined> {
+        const editor = await super.getWidget(uri, options);
+        if (editor) {
+            // Reveal selection before attachment to manage nav stack. (https://github.com/eclipse-theia/theia/issues/8955)
+            this.revealSelection(editor, options, uri);
+        }
+        return editor;
+    }
+
     protected async getOrCreateWidget(uri: URI, options?: EditorOpenerOptions): Promise<EditorWidget> {
         const editor = await super.getOrCreateWidget(uri, options);
         // Reveal selection before attachment to manage nav stack. (https://github.com/eclipse-theia/theia/issues/8955)