Fix #32631

Make tree view data providers disposable
On main tree views disposed
- Deregister and dispose data providers

src/vs/workbench/api/electron-browser/mainThreadTreeViews.ts

@@ -6,6 +6,7 @@
 
 import Event, { Emitter } from 'vs/base/common/event';
 import { TPromise } from 'vs/base/common/winjs.base';
+import { Disposable } from 'vs/base/common/lifecycle';
 import { ExtHostContext, MainThreadTreeViewsShape, ExtHostTreeViewsShape, MainContext, IExtHostContext } from '../node/extHost.protocol';
 import { IMessageService, Severity } from 'vs/platform/message/common/message';
 import { ViewsRegistry } from 'vs/workbench/parts/views/browser/viewsRegistry';
@@ -13,7 +14,7 @@ import { ITreeViewDataProvider, ITreeItem, TreeItemCollapsibleState } from 'vs/w
 import { extHostNamedCustomer } from 'vs/workbench/api/electron-browser/extHostCustomers';
 
 @extHostNamedCustomer(MainContext.MainThreadTreeViews)
-export class MainThreadTreeViews implements MainThreadTreeViewsShape {
+export class MainThreadTreeViews extends Disposable implements MainThreadTreeViewsShape {
 
 	private _proxy: ExtHostTreeViewsShape;
 
@@ -21,16 +22,12 @@ export class MainThreadTreeViews implements MainThreadTreeViewsShape {
 		extHostContext: IExtHostContext,
 		@IMessageService private messageService: IMessageService
 	) {
+		super();
 		this._proxy = extHostContext.get(ExtHostContext.ExtHostTreeViews);
 	}
 
-	public dispose(): void {
-		// TODO@Sandeep: please implement this
-		// will be called when the extension host process is gone.
-	}
-
 	$registerView(treeViewId: string): void {
-		ViewsRegistry.registerTreeViewDataProvider(treeViewId, new TreeViewDataProvider(treeViewId, this._proxy, this.messageService));
+		ViewsRegistry.registerTreeViewDataProvider(treeViewId, this._register(new TreeViewDataProvider(treeViewId, this._proxy, this.messageService)));
 	}
 
 	$refresh(treeViewId: string, treeItemHandles: number[]): void {
@@ -39,6 +36,11 @@ export class MainThreadTreeViews implements MainThreadTreeViewsShape {
 			treeViewDataProvider.refresh(treeItemHandles);
 		}
 	}
+
+	dispose(): void {
+		ViewsRegistry.deregisterTreeViewDataProviders();
+		super.dispose();
+	}
 }
 
 type TreeItemHandle = number;
@@ -48,6 +50,9 @@ class TreeViewDataProvider implements ITreeViewDataProvider {
 	private _onDidChange: Emitter<ITreeItem[] | undefined | null> = new Emitter<ITreeItem[] | undefined | null>();
 	readonly onDidChange: Event<ITreeItem[] | undefined | null> = this._onDidChange.event;
 
+	private _onDispose: Emitter<void> = new Emitter<void>();
+	readonly onDispose: Event<void> = this._onDispose.event;
+
 	private childrenMap: Map<TreeItemHandle, TreeItemHandle[]> = new Map<TreeItemHandle, TreeItemHandle[]>();
 	private itemsMap: Map<TreeItemHandle, ITreeItem> = new Map<TreeItemHandle, ITreeItem>();
 
@@ -94,6 +99,10 @@ class TreeViewDataProvider implements ITreeViewDataProvider {
 		}
 	}
 
+	dispose(): void {
+		this._onDispose.fire();
+	}
+
 	private clearChildren(treeItemHandle: TreeItemHandle): void {
 		const children = this.childrenMap.get(treeItemHandle);
 		if (children) {

src/vs/workbench/parts/views/browser/treeView.ts

@@ -40,7 +40,6 @@ export class TreeView extends CollapsibleView {
 	private activated: boolean = false;
 	private treeInputPromise: TPromise<void>;
 
-	private dataProviderRegisteredListener: IDisposable;
 	private dataProviderElementChangeListener: IDisposable;
 	private disposables: IDisposable[] = [];
 
@@ -138,14 +137,13 @@ export class TreeView extends CollapsibleView {
 					this.treeInputPromise = this.tree.setInput(new Root());
 				} else {
 					this.treeInputPromise = new TPromise<void>((c, e) => {
-						this.dataProviderRegisteredListener = ViewsRegistry.onTreeViewDataProviderRegistered(id => {
+						this.disposables.push(ViewsRegistry.onTreeViewDataProviderRegistered(id => {
 							if (this.id === id) {
 								if (this.listenToDataProvider()) {
 									this.tree.setInput(new Root()).then(() => c(null));
-									this.dataProviderRegisteredListener.dispose();
 								}
 							}
-						});
+						}));
 					});
 				}
 			}
@@ -161,6 +159,11 @@ export class TreeView extends CollapsibleView {
 				this.dataProviderElementChangeListener.dispose();
 			}
 			this.dataProviderElementChangeListener = dataProvider.onDidChange(element => this.refresh(element));
+			const disposable = dataProvider.onDispose(() => {
+				this.dataProviderElementChangeListener.dispose();
+				this.tree.setInput(new Root());
+				disposable.dispose();
+			});
 			return true;
 		}
 		return false;
@@ -191,9 +194,6 @@ export class TreeView extends CollapsibleView {
 	}
 
 	dispose(): void {
-		if (this.dataProviderRegisteredListener) {
-			this.dataProviderRegisteredListener.dispose();
-		}
 		dispose(this.disposables);
 		if (this.dataProviderElementChangeListener) {
 			this.dataProviderElementChangeListener.dispose();
@@ -222,6 +222,9 @@ class TreeDataSource implements IDataSource {
 	}
 
 	public hasChildren(tree: ITree, node: ITreeItem): boolean {
+		if (!this.getDataProvider()) {
+			return false;
+		}
 		return node.collapsibleState === TreeItemCollapsibleState.Collapsed || node.collapsibleState === TreeItemCollapsibleState.Expanded;
 	}
 

src/vs/workbench/parts/views/browser/viewsRegistry.ts

@@ -63,6 +63,8 @@ export interface IViewsRegistry {
 
 	registerTreeViewDataProvider(id: string, factory: ITreeViewDataProvider): void;
 
+	deregisterTreeViewDataProviders(): void;
+
 	getViews(loc: ViewLocation): IViewDescriptor[];
 
 	getTreeViewDataProvider(id: string): ITreeViewDataProvider;
@@ -113,6 +115,10 @@ export const ViewsRegistry: IViewsRegistry = new class {
 		this._onTreeViewDataProviderRegistered.fire(id);
 	}
 
+	deregisterTreeViewDataProviders(): void {
+		this._treeViewDataPoviders.clear();
+	}
+
 	getViews(loc: ViewLocation): IViewDescriptor[] {
 		return this._views.get(loc) || [];
 	}

src/vs/workbench/parts/views/common/views.ts

@@ -41,6 +41,8 @@ export interface ITreeViewDataProvider {
 
 	onDidChange: Event<ITreeItem[] | undefined | null>;
 
+	onDispose: Event<void>;
+
 	getElements(): TPromise<ITreeItem[]>;
 
 	getChildren(element: ITreeItem): TPromise<ITreeItem[]>;