add multi-root file viewer

package.json

@@ -232,6 +232,11 @@
 				{
 					"id": "bazelTaskOutline",
 					"name": "Bazel Run Targets"
+				},
+				{
+					"id": "rootFileViewer",
+					"name": "Project Root (Files)",
+					"when": "isMultiRoot"
 				}
 			]
 		},

src/extension.ts

@@ -21,6 +21,7 @@ import { registerLSClient } from './loggingTCPServer';
 import { ProjectViewManager } from './projectViewManager';
 import { BazelRunTargetProvider } from './provider/bazelRunTargetProvider';
 import { BazelTaskProvider } from './provider/bazelTaskProvider';
+import { RootFileViewProvider } from './provider/rootFileViewProvider';
 import {
 	getWorkspaceRoot,
 	initBazelProjectFile,
@@ -45,6 +46,10 @@ export async function activate(context: ExtensionContext) {
 		BazelRunTargetProvider.instance
 	);
 	tasks.registerTaskProvider('bazel', new BazelTaskProvider());
+	window.registerTreeDataProvider(
+		'rootFileViewer',
+		RootFileViewProvider.instance
+	);
 
 	BazelLanguageServerTerminal.trace('extension activated');
 
@@ -66,6 +71,11 @@ export async function activate(context: ExtensionContext) {
 		'isBazelWorkspaceRoot',
 		isBazelWorkspaceRoot()
 	);
+	commands.executeCommand(
+		'setContext',
+		'isMultiRoot',
+		workspace.workspaceFile?.fsPath.includes('code-workspace')
+	);
 	// create .eclipse/.bazelproject file if DNE
 	if (isBazelWorkspaceRoot()) {
 		initBazelProjectFile();
@@ -134,7 +144,7 @@ export async function activate(context: ExtensionContext) {
 	registerLSClient();
 }
 
-export function deactivate() {}
+export function deactivate() { }
 
 function syncProjectView(): void {
 	if (!isRedhatJavaReady()) {

src/provider/rootFileViewProvider.ts

@@ -0,0 +1,76 @@
+import path from 'path';
+import {
+	Event,
+	EventEmitter,
+	FileSystemWatcher,
+	ProviderResult,
+	RelativePattern,
+	ThemeIcon,
+	TreeDataProvider,
+	TreeItem,
+	TreeItemCollapsibleState,
+	Uri,
+	workspace,
+} from 'vscode';
+import { getWorkspaceRoot } from '../util';
+
+const WORKSPACE_ROOT = getWorkspaceRoot();
+
+export class RootFileViewProvider implements TreeDataProvider<string> {
+	private static _instance: RootFileViewProvider;
+
+	private _filesWatcher: FileSystemWatcher;
+	private _onDidChangeTreeData: EventEmitter<string | undefined | void> =
+		new EventEmitter<string | undefined | void>();
+	readonly onDidChangeTreeData: Event<string | undefined | void> =
+		this._onDidChangeTreeData.event;
+
+	private constructor() {
+		this._filesWatcher = workspace.createFileSystemWatcher(
+			new RelativePattern(WORKSPACE_ROOT, '*')
+		);
+		this._filesWatcher.onDidChange((f) => this._onDidChangeTreeData.fire());
+		this._filesWatcher.onDidCreate((f) => this._onDidChangeTreeData.fire());
+		this._filesWatcher.onDidDelete((f) => this._onDidChangeTreeData.fire());
+	}
+
+	public static get instance(): RootFileViewProvider {
+		if (!this._instance) {
+			this._instance = new RootFileViewProvider();
+		}
+		return this._instance;
+	}
+
+	getTreeItem(element: string): TreeItem | Thenable<TreeItem> {
+		return new FileItem(element);
+	}
+	getChildren(element?: string | undefined): ProviderResult<string[]> {
+		if (!element) {
+			return workspace.fs
+				.readDirectory(Uri.file(WORKSPACE_ROOT))
+				.then((val) => {
+					return val.filter((v) => v[1] === 1).map((v) => v[0]);
+				});
+		}
+		return [];
+	}
+}
+
+class FileItem extends TreeItem {
+	constructor(fileName: string, collapsibleState?: TreeItemCollapsibleState) {
+		super(fileName, collapsibleState);
+		this.command = {
+			title: fileName,
+			command: 'vscode.open',
+			arguments: [Uri.file(`${WORKSPACE_ROOT}${path.sep}${fileName}`)],
+		};
+		switch (fileName.split('.').reverse()[0]) {
+			case 'json':
+				this.iconPath = new ThemeIcon('json');
+				break;
+			default:
+				this.iconPath = new ThemeIcon('file');
+				break;
+		}
+	}
+}