Implement workspace.workspaceFile extension API

This first implementation returns the Uri location of the workspace
file even if it is untitled (i.e. saved on a temporary default
location).

Issue: eclipse-theia#8994

Signed-off-by: Alvaro Sanchez-Leon <alvaro.sanchez-leon@ericsson.com>

packages/plugin-ext/src/common/plugin-api-rpc.ts

@@ -552,10 +552,12 @@ export interface WorkspaceMain {
     $unregisterTextDocumentContentProvider(scheme: string): void;
     $onTextDocumentContentChange(uri: string, content: string): void;
     $updateWorkspaceFolders(start: number, deleteCount?: number, ...rootsToAdd: string[]): Promise<void>;
+    $getWorkspace(): Promise<files.FileStat | undefined>;
 }
 
 export interface WorkspaceExt {
     $onWorkspaceFoldersChanged(event: WorkspaceRootsChangeEvent): void;
+    $onWorkspaceLocationChanged(event: files.FileStat | undefined): void;
     $provideTextDocumentContent(uri: string): Promise<string | undefined>;
     $onTextSearchResult(searchRequestId: number, done: boolean, result?: SearchInWorkspaceResult): void;
 }

packages/plugin-ext/src/main/browser/workspace-main.ts

@@ -31,6 +31,7 @@ import { Emitter, Event, ResourceResolver, CancellationToken } from '@theia/core
 import { PluginServer } from '../../common/plugin-protocol';
 import { FileSystemPreferences } from '@theia/filesystem/lib/browser';
 import { SearchInWorkspaceService } from '@theia/search-in-workspace/lib/browser/search-in-workspace-service';
+import { FileStat } from '@theia/filesystem/lib/common/files';
 
 export class WorkspaceMainImpl implements WorkspaceMain, Disposable {
 
@@ -73,6 +74,9 @@ export class WorkspaceMainImpl implements WorkspaceMain, Disposable {
         this.toDispose.push(this.workspaceService.onWorkspaceChanged(roots => {
             this.processWorkspaceFoldersChanged(roots.map(root => root.resource.toString()));
         }));
+        this.toDispose.push(this.workspaceService.onWorkspaceLocationChanged(stat => {
+            this.proxy.$onWorkspaceLocationChanged(stat);
+        }));
     }
 
     dispose(): void {
@@ -102,6 +106,10 @@ export class WorkspaceMainImpl implements WorkspaceMain, Disposable {
         return this.roots.some((root, index) => root !== roots[index]);
     }
 
+    async $getWorkspace(): Promise<FileStat | undefined> {
+        return this.workspaceService.workspace;
+    }
+
     $pickWorkspaceFolder(options: WorkspaceFolderPickOptionsMain): Promise<theia.WorkspaceFolder | undefined> {
         return new Promise((resolve, reject) => {
             // Return undefined if workspace root is not set

packages/plugin-ext/src/plugin/plugin-context.ts

@@ -455,6 +455,9 @@ export function createAPIFactory(
             get workspaceFolders(): theia.WorkspaceFolder[] | undefined {
                 return workspaceExt.workspaceFolders;
             },
+            get workspaceFile(): Uri | undefined {
+                return workspaceExt.workspaceFile;
+            },
             get name(): string | undefined {
                 return workspaceExt.name;
             },

packages/plugin-ext/src/plugin/workspace.ts

@@ -41,6 +41,7 @@ import { Schemes } from '../common/uri-components';
 import { toWorkspaceFolder } from './type-converters';
 import { MessageRegistryExt } from './message-registry';
 import * as Converter from './type-converters';
+import { FileStat } from '@theia/filesystem/lib/common/files';
 
 export class WorkspaceExtImpl implements WorkspaceExt {
 
@@ -50,6 +51,7 @@ export class WorkspaceExtImpl implements WorkspaceExt {
     public readonly onDidChangeWorkspaceFolders: Event<theia.WorkspaceFoldersChangeEvent> = this.workspaceFoldersChangedEmitter.event;
 
     private folders: theia.WorkspaceFolder[] | undefined;
+    private workspaceFileUri: theia.Uri | undefined;
     private documentContentProviders = new Map<string, theia.TextDocumentContentProvider>();
     private searchInWorkspaceEmitter: Emitter<{ result?: theia.TextSearchResult, searchId: number }> = new Emitter<{ result?: theia.TextSearchResult, searchId: number }>();
     protected workspaceSearchSequence: number = 0;
@@ -72,6 +74,10 @@ export class WorkspaceExtImpl implements WorkspaceExt {
         return this.folders;
     }
 
+    get workspaceFile(): theia.Uri | undefined {
+        return this.workspaceFileUri;
+    }
+
     get name(): string | undefined {
         if (this.workspaceFolders && this.workspaceFolders.length > 0) {
             return new Path(this.workspaceFolders[0].uri.path).base;
@@ -87,9 +93,15 @@ export class WorkspaceExtImpl implements WorkspaceExt {
 
         this.folders = newFolders;
 
+        this.refreshWorkspaceFile();
+
         this.workspaceFoldersChangedEmitter.fire(delta);
     }
 
+    $onWorkspaceLocationChanged(stat: FileStat | undefined): void {
+        this.updateWorkSpace(stat);
+    }
+
     $onTextSearchResult(searchRequestId: number, done: boolean, result?: SearchInWorkspaceResult): void {
         if (result) {
             result.matches.map(next => {
@@ -395,4 +407,15 @@ export class WorkspaceExtImpl implements WorkspaceExt {
         return true;
     }
 
+    private async refreshWorkspaceFile(): Promise<void> {
+        const workspace = await this.proxy.$getWorkspace();
+        this.updateWorkSpace(workspace);
+    }
+
+    private updateWorkSpace(workspace: FileStat | undefined): void {
+        // A workspace directory implies an undefined workspace file
+        if (workspace && !workspace.isDirectory) {
+            this.workspaceFileUri = URI.parse(workspace.resource.toString());
+        }
+    }
 }

packages/plugin/src/theia.d.ts

@@ -5145,6 +5145,22 @@ declare module '@theia/plugin' {
          */
         export let workspaceFolders: WorkspaceFolder[] | undefined;
 
+        /**
+         * The location of the workspace file, for example:
+         *
+         * `file:///Users/name/Development/myProject.code-workspace`
+         *
+         * Depending on the workspace that is opened, the value will be:
+         *  * `undefined` when no workspace or a single folder is opened
+         *  * the path of the workspace file as `Uri` otherwise.
+         *
+         * **Note:** it is not advised to use `workspace.workspaceFile` to write
+         * configuration data into the file.
+         * 
+         * @readonly
+         */
+        export const workspaceFile: Uri | undefined;
+
         /**
          * The name of the workspace. `undefined` when no folder
          * has been opened.