Handle deleted files in open editors widget

packages/filesystem/src/browser/filesystem-frontend-contribution.ts

@@ -17,7 +17,7 @@
 import { injectable, inject } from '@theia/core/shared/inversify';
 import URI from '@theia/core/lib/common/uri';
 import { environment } from '@theia/core/shared/@theia/application-package/lib/environment';
-import { MaybePromise, SelectionService, isCancelled } from '@theia/core/lib/common';
+import { MaybePromise, SelectionService, isCancelled, Emitter } from '@theia/core/lib/common';
 import { Command, CommandContribution, CommandRegistry } from '@theia/core/lib/common/command';
 import {
     FrontendApplicationContribution, ApplicationShell,
@@ -77,6 +77,9 @@ export class FileSystemFrontendContribution implements FrontendApplicationContri
     @inject(FileService)
     protected readonly fileService: FileService;
 
+    protected onDidChangeEditorFileEmitter = new Emitter<{ editor: NavigatableWidget, type: FileChangeType }>();
+    readonly onDidChangeEditorFile = this.onDidChangeEditorFileEmitter.event;
+
     protected readonly userOperations = new Map<number, Deferred<void>>();
     protected queueUserOperation(event: UserFileOperationEvent): void {
         const moveOperation = new Deferred<void>();
@@ -301,13 +304,15 @@ export class FileSystemFrontendContribution implements FrontendApplicationContri
             }
             if (!deleted) {
                 widget.title.label += this.deletedSuffix;
+                this.onDidChangeEditorFileEmitter.fire({ editor: widget, type: FileChangeType.DELETED });
             }
             const widgets = toClose.get(uriString) || [];
             widgets.push(widget);
             toClose.set(uriString, widgets);
         } else if (event.contains(uri, FileChangeType.ADDED)) {
             if (deleted) {
                 widget.title.label = widget.title.label.substr(0, label.length - this.deletedSuffix.length);
+                this.onDidChangeEditorFileEmitter.fire({ editor: widget, type: FileChangeType.ADDED });
             }
         }
     }

packages/navigator/src/browser/navigator-frontend-module.ts

@@ -41,6 +41,7 @@ import { bindContributionProvider } from '@theia/core/lib/common';
 import { OpenEditorsTreeDecorator } from './open-editors-widget/navigator-open-editors-decorator-service';
 import { OpenEditorsWidget } from './open-editors-widget/navigator-open-editors-widget';
 import { NavigatorTreeDecorator } from './navigator-decorator-service';
+import { NavigatorDeletedEditorDecorator } from './open-editors-widget/navigator-deleted-editor-decorator';
 
 export default new ContainerModule(bind => {
     bindFileNavigatorPreferences(bind);
@@ -63,6 +64,8 @@ export default new ContainerModule(bind => {
     })).inSingletonScope();
     bindContributionProvider(bind, NavigatorTreeDecorator);
     bindContributionProvider(bind, OpenEditorsTreeDecorator);
+    bind(NavigatorDeletedEditorDecorator).toSelf().inSingletonScope();
+    bind(OpenEditorsTreeDecorator).toService(NavigatorDeletedEditorDecorator);
 
     bind(WidgetFactory).toDynamicValue(({ container }) => ({
         id: OpenEditorsWidget.ID,

packages/navigator/src/browser/open-editors-widget/navigator-deleted-editor-decorator.ts

@@ -0,0 +1,91 @@
+/********************************************************************************
+ * Copyright (C) 2021 Ericsson 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
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * This Source Code may also be made available under the following Secondary
+ * Licenses when the conditions for such availability set forth in the Eclipse
+ * Public License v. 2.0 are satisfied: GNU General Public License, version 2
+ * with the GNU Classpath Exception which is available at
+ * https://www.gnu.org/software/classpath/license.html.
+ *
+ * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
+ ********************************************************************************/
+
+import { injectable, inject, postConstruct } from '@theia/core/shared/inversify';
+import { ApplicationShell, DepthFirstTreeIterator, NavigatableWidget, Tree, TreeDecoration, TreeDecorator } from '@theia/core/lib/browser';
+import { FileSystemFrontendContribution } from '@theia/filesystem/lib/browser/filesystem-frontend-contribution';
+import { Emitter } from '@theia/core';
+import { FileChangeType, FileStatNode } from '@theia/filesystem/lib/browser';
+
+@injectable()
+export class NavigatorDeletedEditorDecorator implements TreeDecorator {
+
+    @inject(FileSystemFrontendContribution)
+    protected readonly fileSystemContribution: FileSystemFrontendContribution;
+    @inject(ApplicationShell)
+    protected readonly shell: ApplicationShell;
+
+    readonly id = 'theia-deleted-editor-decorator';
+    protected readonly onDidChangeDecorationsEmitter = new Emitter();
+    readonly onDidChangeDecorations = this.onDidChangeDecorationsEmitter.event;
+    protected deletedURIs = new Set<string>();
+
+    @postConstruct()
+    init(): void {
+        this.fileSystemContribution.onDidChangeEditorFile(({ editor, type }) => {
+            const uri = editor.getResourceUri()?.toString();
+            if (uri) {
+                if (type === FileChangeType.DELETED) {
+                    this.deletedURIs.add(uri);
+                } else if (type === FileChangeType.ADDED) {
+                    this.deletedURIs.delete(uri);
+                }
+                this.fireDidChangeDecorations((tree: Tree) => this.collectDecorators(tree));
+            }
+        });
+        this.shell.onDidAddWidget(() => {
+            const newDeletedURIs = new Set<string>();
+            this.shell.widgets.forEach(widget => {
+                if (NavigatableWidget.is(widget)) {
+                    const uri = widget.getResourceUri()?.toString();
+                    if (uri && this.deletedURIs.has(uri)) {
+                        newDeletedURIs.add(uri);
+                    }
+                }
+            });
+            this.deletedURIs = newDeletedURIs;
+        });
+    }
+
+    decorations(tree: Tree): Map<string, TreeDecoration.Data> {
+        return this.collectDecorators(tree);
+    }
+
+    protected collectDecorators(tree: Tree): Map<string, TreeDecoration.Data> {
+        const result = new Map<string, TreeDecoration.Data>();
+        if (tree.root === undefined) {
+            return result;
+        }
+        for (const node of new DepthFirstTreeIterator(tree.root)) {
+            if (FileStatNode.is(node)) {
+                const uri = node.uri.toString();
+                if (this.deletedURIs.has(uri)) {
+                    const deletedDecoration: TreeDecoration.Data = {
+                        fontData: {
+                            style: 'line-through',
+                        }
+                    };
+                    result.set(node.id, deletedDecoration);
+                }
+            }
+        }
+        return result;
+    }
+
+    protected fireDidChangeDecorations(event: (tree: Tree) => Map<string, TreeDecoration.Data>): void {
+        this.onDidChangeDecorationsEmitter.fire(event);
+    }
+}

packages/navigator/src/browser/open-editors-widget/navigator-open-editors-tree-model.ts

@@ -31,6 +31,8 @@ import {
 import { WorkspaceService } from '@theia/workspace/lib/browser';
 import debounce = require('@theia/core/shared/lodash.debounce');
 import { DisposableCollection } from '@theia/core/lib/common';
+import { FileStat } from '@theia/filesystem/lib/common/files';
+
 export interface OpenEditorNode extends FileStatNode {
     widget: Widget;
 };
@@ -60,6 +62,8 @@ export class OpenEditorsModel extends FileTreeModel {
     // Last collection of editors before a layout modification, used to detect changes in widget ordering
     protected _lastEditorWidgetsByArea = new Map<ApplicationShell.Area, NavigatableWidget[]>();
 
+    protected cachedFileStats = new Map<string, FileStat>();
+
     get editorWidgets(): NavigatableWidget[] {
         const editorWidgets: NavigatableWidget[] = [];
         this._editorWidgetsByArea.forEach(widgets => editorWidgets.push(...widgets));
@@ -84,7 +88,15 @@ export class OpenEditorsModel extends FileTreeModel {
                 this.selectNode(nodeToSelect);
             }
         }));
-        this.toDispose.push(this.applicationShell.onDidAddWidget(() => this.updateOpenWidgets()));
+        this.toDispose.push(this.applicationShell.onDidAddWidget(async () => {
+            await this.updateOpenWidgets();
+            const existingWidgetIds = new Set(this.editorWidgets.map(widget => widget.id));
+            this.cachedFileStats.forEach((_fileStat, id) => {
+                if (!existingWidgetIds.has(id)) {
+                    this.cachedFileStats.delete(id);
+                }
+            });
+        }));
         this.toDispose.push(this.applicationShell.onDidRemoveWidget(() => this.updateOpenWidgets()));
         // Check for tabs rearranged in main and bottom
         this.applicationShell.mainPanel.layoutModified.connect(() => this.doUpdateOpenWidgets('main'));
@@ -187,7 +199,19 @@ export class OpenEditorsModel extends FileTreeModel {
             for (const widget of widgetsInArea) {
                 const uri = widget.getResourceUri();
                 if (uri) {
-                    const fileStat = await this.fileService.resolve(uri);
+                    let fileStat: FileStat;
+                    try {
+                        fileStat = await this.fileService.resolve(uri);
+                        this.cachedFileStats.set(widget.id, fileStat);
+                    } catch {
+                        const cachedStat = this.cachedFileStats.get(widget.id);
+                        if (cachedStat) {
+                            fileStat = cachedStat;
+                        } else {
+                            continue;
+                        }
+                    }
+
                     const openEditorNode: OpenEditorNode = {
                         id: widget.id,
                         fileStat,