some gc sync'ing between main and ext host

src/typings/gc-signals.d.ts

+declare module 'gc-signals' {
+    export interface GCSignal {
+    }
+    /**
+     * Create a new GC signal. When being garbage collected the passed
+     * value is stored for later consumption.
+     */
+    export const GCSignal: {
+        new (id: number): GCSignal;
+    };
+    /**
+     * Consume ids of garbage collected signals.
+     */
+    export function consumeSignals(): number[];
+    export function onDidGarbageCollectSignals(callback: (ids: number[]) => any): {
+        dispose(): void;
+    };
+    export function trackGarbageCollection(obj: any, id: number): number;
+}
\ No newline at end of file

src/vs/workbench/api/node/extHost.api.impl.ts

@@ -17,6 +17,7 @@ import {ExtHostConfiguration} from 'vs/workbench/api/node/extHostConfiguration';
 import {ExtHostDiagnostics} from 'vs/workbench/api/node/extHostDiagnostics';
 import {ExtHostWorkspace} from 'vs/workbench/api/node/extHostWorkspace';
 import {ExtHostQuickOpen} from 'vs/workbench/api/node/extHostQuickOpen';
+import {ExtHostHeapMonitor} from 'vs/workbench/api/node/extHostHeapMonitor';
 import {ExtHostStatusBar} from 'vs/workbench/api/node/extHostStatusBar';
 import {ExtHostCommands} from 'vs/workbench/api/node/extHostCommands';
 import {ExtHostOutputService} from 'vs/workbench/api/node/extHostOutputService';
@@ -99,12 +100,13 @@ export class ExtHostAPIImplementation {
 		// Addressable instances
 		const col = new InstanceCollection();
 
+		const extHostHeapMonitor = col.define(ExtHostContext.ExtHostHeapMonitor).set<ExtHostHeapMonitor>(new ExtHostHeapMonitor());
 		const extHostDocuments = col.define(ExtHostContext.ExtHostDocuments).set<ExtHostDocuments>(new ExtHostDocuments(threadService));
 		const extHostEditors = col.define(ExtHostContext.ExtHostEditors).set<ExtHostEditors>(new ExtHostEditors(threadService, extHostDocuments));
 		const extHostCommands = col.define(ExtHostContext.ExtHostCommands).set<ExtHostCommands>(new ExtHostCommands(threadService, extHostEditors));
 		const extHostConfiguration = col.define(ExtHostContext.ExtHostConfiguration).set<ExtHostConfiguration>(new ExtHostConfiguration(threadService.get(MainContext.MainThreadConfiguration)));
 		const extHostDiagnostics = col.define(ExtHostContext.ExtHostDiagnostics).set<ExtHostDiagnostics>(new ExtHostDiagnostics(threadService));
-		const languageFeatures = col.define(ExtHostContext.ExtHostLanguageFeatures).set<ExtHostLanguageFeatures>(new ExtHostLanguageFeatures(threadService, extHostDocuments, extHostCommands, extHostDiagnostics));
+		const languageFeatures = col.define(ExtHostContext.ExtHostLanguageFeatures).set<ExtHostLanguageFeatures>(new ExtHostLanguageFeatures(threadService, extHostDocuments, extHostCommands, extHostHeapMonitor, extHostDiagnostics));
 		const extHostFileSystemEvent = col.define(ExtHostContext.ExtHostFileSystemEventService).set<ExtHostFileSystemEventService>(new ExtHostFileSystemEventService());
 		const extHostQuickOpen = col.define(ExtHostContext.ExtHostQuickOpen).set<ExtHostQuickOpen>(new ExtHostQuickOpen(threadService));
 		col.define(ExtHostContext.ExtHostExtensionService).set(extensionService);

src/vs/workbench/api/node/extHost.contribution.ts

@@ -32,6 +32,7 @@ import {MainThreadTerminalService} from './mainThreadTerminalService';
 import {MainThreadWorkspace} from './mainThreadWorkspace';
 import {MainProcessExtensionService} from './mainThreadExtensionService';
 import {MainThreadFileSystemEventService} from './mainThreadFileSystemEventService';
+import {MainThreadHeapMonitor} from './mainThreadHeapMonitor';
 
 // --- other interested parties
 import {MainProcessTextMateSyntax} from 'vs/editor/node/textMate/TMSyntax';
@@ -87,6 +88,7 @@ export class ExtHostContribution implements IWorkbenchContribution {
 		create(JSONValidationExtensionPoint);
 		create(LanguageConfigurationFileHandler);
 		create(MainThreadFileSystemEventService);
+		create(MainThreadHeapMonitor);
 	}
 }
 

src/vs/workbench/api/node/extHost.protocol.ts

@@ -265,6 +265,10 @@ export abstract class ExtHostFileSystemEventServiceShape {
 	$onFileEvent(events: FileSystemEvents) { throw ni(); }
 }
 
+export abstract class ExtHostHeapMonitorShape {
+	$onGarbageCollection(ids: number[]): void { throw ni(); }
+}
+
 export abstract class ExtHostLanguageFeaturesShape {
 	$provideDocumentSymbols(handle: number, resource: URI): TPromise<modes.SymbolInformation[]> { throw ni(); }
 	$provideCodeLenses(handle: number, resource: URI): TPromise<modes.ICodeLensSymbol[]> { throw ni(); }
@@ -321,6 +325,7 @@ export const ExtHostContext = {
 	ExtHostDocuments: createExtId<ExtHostDocumentsShape>('ExtHostDocuments', ExtHostDocumentsShape),
 	ExtHostEditors: createExtId<ExtHostEditorsShape>('ExtHostEditors', ExtHostEditorsShape),
 	ExtHostFileSystemEventService: createExtId<ExtHostFileSystemEventServiceShape>('ExtHostFileSystemEventService', ExtHostFileSystemEventServiceShape),
+	ExtHostHeapMonitor: createExtId<ExtHostHeapMonitorShape>('ExtHostHeapMonitor', ExtHostHeapMonitorShape),
 	ExtHostLanguageFeatures: createExtId<ExtHostLanguageFeaturesShape>('ExtHostLanguageFeatures', ExtHostLanguageFeaturesShape),
 	ExtHostQuickOpen: createExtId<ExtHostQuickOpenShape>('ExtHostQuickOpen', ExtHostQuickOpenShape),
 	ExtHostExtensionService: createExtId<ExtHostExtensionServiceShape>('ExtHostExtensionService', ExtHostExtensionServiceShape),

src/vs/workbench/api/node/extHostHeapMonitor.ts

+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+'use strict';
+
+import {ExtHostHeapMonitorShape} from './extHost.protocol';
+
+export class ExtHostHeapMonitor extends ExtHostHeapMonitorShape {
+
+	private static _idPool = 0;
+
+	private _data: { [n: number]: any } = Object.create(null);
+	private _callbacks: { [n: number]: Function } = Object.create(null);
+
+	private _mixinObjectIdentifier(obj: any): number {
+		const id = ExtHostHeapMonitor._idPool++;
+
+		Object.defineProperties(obj, {
+			'$heap_ident': {
+				value: id,
+				enumerable: true,
+				configurable: false,
+				writable: false
+			},
+			'$mid': {
+				value: 3,
+				enumerable: true,
+				configurable: false,
+				writable: false
+			}
+		});
+
+		return id;
+	}
+
+	linkObjects(external: any, internal: any, callback?: () => any) {
+		const id = this._mixinObjectIdentifier(external);
+		this._data[id] = internal;
+		if (typeof callback === 'function') {
+			this._callbacks[id] = callback;
+		}
+	}
+
+	getInternalObject<T>(external: any): T {
+		const id = external.$heap_ident;
+		if (typeof id === 'number') {
+			return this._data[id];
+		}
+	}
+
+	$onGarbageCollection(ids: number[]): void {
+		for (const id of ids) {
+			delete this._data[id];
+			const callback = this._callbacks[id];
+			if (callback) {
+				delete this._callbacks[id];
+				setTimeout(callback);
+			}
+		}
+	}
+}
\ No newline at end of file

src/vs/workbench/api/node/extHostLanguageFeatures.ts

@@ -10,9 +10,10 @@ import {IDisposable, dispose} from 'vs/base/common/lifecycle';
 import {IThreadService} from 'vs/workbench/services/thread/common/threadService';
 import * as vscode from 'vscode';
 import * as TypeConverters from 'vs/workbench/api/node/extHostTypeConverters';
-import {Range, Disposable, CompletionList} from 'vs/workbench/api/node/extHostTypes';
+import {Range, Disposable, CompletionList, CompletionItem} from 'vs/workbench/api/node/extHostTypes';
 import {IPosition, IRange, ISingleEditOperation} from 'vs/editor/common/editorCommon';
 import * as modes from 'vs/editor/common/modes';
+import {ExtHostHeapMonitor} from 'vs/workbench/api/node/extHostHeapMonitor';
 import {ExtHostDocuments} from 'vs/workbench/api/node/extHostDocuments';
 import {ExtHostCommands} from 'vs/workbench/api/node/extHostCommands';
 import {ExtHostDiagnostics} from 'vs/workbench/api/node/extHostDiagnostics';
@@ -503,11 +504,12 @@ interface ISuggestion2 extends modes.ISuggestion {
 class SuggestAdapter {
 
 	private _documents: ExtHostDocuments;
+	private _heapMonitor: ExtHostHeapMonitor;
 	private _provider: vscode.CompletionItemProvider;
-	private _cache: { [key: string]: { list: CompletionList; disposables: IDisposable[]; } } = Object.create(null);
 
-	constructor(documents: ExtHostDocuments, provider: vscode.CompletionItemProvider) {
+	constructor(documents: ExtHostDocuments, heapMonitor: ExtHostHeapMonitor, provider: vscode.CompletionItemProvider) {
 		this._documents = documents;
+		this._heapMonitor = heapMonitor;
 		this._provider = provider;
 	}
 
@@ -516,12 +518,6 @@ class SuggestAdapter {
 		const doc = this._documents.getDocumentData(resource).document;
 		const pos = TypeConverters.toPosition(position);
 
-		const key = resource.toString();
-		if (this._cache[key]) {
-			dispose(this._cache[key].disposables);
-			delete this._cache[key];
-		}
-
 		return asWinJsPromise<vscode.CompletionItem[]|vscode.CompletionList>(token => this._provider.provideCompletionItems(doc, pos, token)).then(value => {
 
 			const result: modes.ISuggestResult = {
@@ -533,7 +529,6 @@ class SuggestAdapter {
 			const wordRangeBeforePos = (doc.getWordRangeAtPosition(pos) || new Range(pos, pos))
 				.with({ end: pos });
 
-			const disposables: IDisposable[] = [];
 			let list: CompletionList;
 			if (!value) {
 				// undefined and null are valid results
@@ -550,8 +545,11 @@ class SuggestAdapter {
 			for (let i = 0; i < list.items.length; i++) {
 
 				const item = list.items[i];
+				const disposables: IDisposable[] = [];
 				const suggestion = <ISuggestion2> TypeConverters.Suggest.from(item, disposables);
 
+				this._heapMonitor.linkObjects(suggestion, item, () => dispose(disposables));
+
 				if (item.textEdit) {
 
 					const editRange = item.textEdit.range;
@@ -581,25 +579,22 @@ class SuggestAdapter {
 				result.suggestions.push(suggestion);
 			}
 
-			// cache for details call
-			this._cache[key] = { list, disposables };
-
 			return result;
 		});
 	}
 
 	resolveCompletionItem(resource: URI, position: IPosition, suggestion: modes.ISuggestion): TPromise<modes.ISuggestion> {
-		if (typeof this._provider.resolveCompletionItem !== 'function' || !this._cache[resource.toString()]) {
+
+		if (typeof this._provider.resolveCompletionItem !== 'function') {
 			return TPromise.as(suggestion);
 		}
 
-		const {list, disposables} = this._cache[resource.toString()];
-		const item = list.items[Number((<ISuggestion2> suggestion).id)];
+		const item = this._heapMonitor.getInternalObject<CompletionItem>(suggestion);
 		if (!item) {
 			return TPromise.as(suggestion);
 		}
 		return asWinJsPromise(token => this._provider.resolveCompletionItem(item, token)).then(resolvedItem => {
-			return TypeConverters.Suggest.from(resolvedItem || item, disposables);
+			return <ISuggestion2> TypeConverters.Suggest.from(resolvedItem || item, []);
 		});
 	}
 }
@@ -670,6 +665,7 @@ export class ExtHostLanguageFeatures extends ExtHostLanguageFeaturesShape {
 	private _proxy: MainThreadLanguageFeaturesShape;
 	private _documents: ExtHostDocuments;
 	private _commands: ExtHostCommands;
+	private _heapMonitor: ExtHostHeapMonitor;
 	private _diagnostics: ExtHostDiagnostics;
 	private _adapter: { [handle: number]: Adapter } = Object.create(null);
 
@@ -677,12 +673,14 @@ export class ExtHostLanguageFeatures extends ExtHostLanguageFeaturesShape {
 		threadService: IThreadService,
 		documents: ExtHostDocuments,
 		commands: ExtHostCommands,
+		heapMonitor: ExtHostHeapMonitor,
 		diagnostics: ExtHostDiagnostics
 	) {
 		super();
 		this._proxy = threadService.get(MainContext.MainThreadLanguageFeatures);
 		this._documents = documents;
 		this._commands = commands;
+		this._heapMonitor = heapMonitor;
 		this._diagnostics = diagnostics;
 	}
 
@@ -869,7 +867,7 @@ export class ExtHostLanguageFeatures extends ExtHostLanguageFeaturesShape {
 
 	registerCompletionItemProvider(selector: vscode.DocumentSelector, provider: vscode.CompletionItemProvider, triggerCharacters: string[]): vscode.Disposable {
 		const handle = this._nextHandle();
-		this._adapter[handle] = new SuggestAdapter(this._documents, provider);
+		this._adapter[handle] = new SuggestAdapter(this._documents, this._heapMonitor, provider);
 		this._proxy.$registerSuggestSupport(handle, selector, triggerCharacters);
 		return this._createDisposable(handle);
 	}

src/vs/workbench/api/node/mainThreadHeapMonitor.ts

+/*---------------------------------------------------------------------------------------------
+ *  Copyright (c) Microsoft Corporation. All rights reserved.
+ *  Licensed under the MIT License. See License.txt in the project root for license information.
+ *--------------------------------------------------------------------------------------------*/
+
+'use strict';
+
+import {IDisposable} from 'vs/base/common/lifecycle';
+import {IThreadService} from 'vs/workbench/services/thread/common/threadService';
+import {ExtHostContext} from './extHost.protocol';
+import {onDidGarbageCollectSignals, consumeSignals, trackGarbageCollection} from 'gc-signals';
+
+export class MainThreadHeapMonitor {
+
+	private _subscription: IDisposable;
+	private _consumeHandle: number;
+
+	constructor( @IThreadService threadService: IThreadService) {
+		const proxy = threadService.get(ExtHostContext.ExtHostHeapMonitor);
+
+		this._subscription = onDidGarbageCollectSignals(ids => {
+			proxy.$onGarbageCollection(ids);
+		});
+
+		this._consumeHandle = setInterval(consumeSignals, 15 * 1000);
+	}
+
+	dispose() {
+		clearInterval(this._consumeHandle);
+		this._subscription.dispose();
+	}
+
+	trackObject(obj: any) {
+		if (typeof obj.$heap_ident === 'number') {
+			trackGarbageCollection(obj, obj.$heap_ident);
+		}
+	}
+}
\ No newline at end of file

src/vs/workbench/api/node/mainThreadLanguageFeatures.ts

@@ -17,6 +17,7 @@ import {Position as EditorPosition} from 'vs/editor/common/core/position';
 import {Range as EditorRange} from 'vs/editor/common/core/range';
 import {ExtHostContext, MainThreadLanguageFeaturesShape, ExtHostLanguageFeaturesShape} from './extHost.protocol';
 import {LanguageConfigurationRegistry, LanguageConfiguration} from 'vs/editor/common/modes/languageConfigurationRegistry';
+import {trackGarbageCollection} from 'gc-signals';
 
 export class MainThreadLanguageFeatures extends MainThreadLanguageFeaturesShape {
 
@@ -180,7 +181,12 @@ export class MainThreadLanguageFeatures extends MainThreadLanguageFeaturesShape
 		this._registrations[handle] = modes.SuggestRegistry.register(selector, <modes.ISuggestSupport>{
 			triggerCharacters: triggerCharacters,
 			provideCompletionItems: (model:IReadOnlyModel, position:EditorPosition, token:CancellationToken): Thenable<modes.ISuggestResult> => {
-				return wireCancellationToken(token, this._proxy.$provideCompletionItems(handle, model.uri, position));
+				return wireCancellationToken(token, this._proxy.$provideCompletionItems(handle, model.uri, position)).then(result => {
+					for (const suggestion of result.suggestions) {
+						trackGarbageCollection(suggestion, (<any>suggestion).$heap_ident);
+					}
+					return result;
+				});
 			},
 			resolveCompletionItem: (model:IReadOnlyModel, position:EditorPosition, suggestion: modes.ISuggestion, token: CancellationToken): Thenable<modes.ISuggestion> => {
 				return wireCancellationToken(token, this._proxy.$resolveCompletionItem(handle, model.uri, position, suggestion));

src/vs/workbench/test/node/api/extHostApiCommands.test.ts

@@ -23,6 +23,7 @@ import {ExtHostLanguageFeatures} from 'vs/workbench/api/node/extHostLanguageFeat
 import {MainThreadLanguageFeatures} from 'vs/workbench/api/node/mainThreadLanguageFeatures';
 import {registerApiCommands} from 'vs/workbench/api/node/extHostApiCommands';
 import {ExtHostCommands} from 'vs/workbench/api/node/extHostCommands';
+import {ExtHostHeapMonitor} from 'vs/workbench/api/node/extHostHeapMonitor';
 import {MainThreadCommands} from 'vs/workbench/api/node/mainThreadCommands';
 import {ExtHostDocuments} from 'vs/workbench/api/node/extHostDocuments';
 import * as ExtHostTypeConverters from 'vs/workbench/api/node/extHostTypeConverters';
@@ -108,7 +109,7 @@ suite('ExtHostLanguageFeatureCommands', function() {
 		const diagnostics = new ExtHostDiagnostics(threadService);
 		threadService.set(ExtHostContext.ExtHostDiagnostics, diagnostics);
 
-		extHost = new ExtHostLanguageFeatures(threadService, extHostDocuments, commands, diagnostics);
+		extHost = new ExtHostLanguageFeatures(threadService, extHostDocuments, commands, new ExtHostHeapMonitor(), diagnostics);
 		threadService.set(ExtHostContext.ExtHostLanguageFeatures, extHost);
 
 		mainThread = threadService.setTestInstance(MainContext.MainThreadLanguageFeatures, instantiationService.createInstance(MainThreadLanguageFeatures));

src/vs/workbench/test/node/api/extHostLanguageFeatures.test.ts

@@ -39,6 +39,7 @@ import {getLinks} from 'vs/editor/contrib/links/common/links';
 import {asWinJsPromise} from 'vs/base/common/async';
 import {MainContext, ExtHostContext} from 'vs/workbench/api/node/extHost.protocol';
 import {ExtHostDiagnostics} from 'vs/workbench/api/node/extHostDiagnostics';
+import {ExtHostHeapMonitor} from 'vs/workbench/api/node/extHostHeapMonitor';
 
 const defaultSelector = { scheme: 'far' };
 const model: EditorCommon.IModel = EditorModel.createFromString(
@@ -97,7 +98,7 @@ suite('ExtHostLanguageFeatures', function() {
 		const diagnostics = new ExtHostDiagnostics(threadService);
 		threadService.set(ExtHostContext.ExtHostDiagnostics, diagnostics);
 
-		extHost = new ExtHostLanguageFeatures(threadService, extHostDocuments, commands, diagnostics);
+		extHost = new ExtHostLanguageFeatures(threadService, extHostDocuments, commands, new ExtHostHeapMonitor(), diagnostics);
 		threadService.set(ExtHostContext.ExtHostLanguageFeatures, extHost);
 
 		mainThread = <MainThreadLanguageFeatures>threadService.setTestInstance(MainContext.MainThreadLanguageFeatures, instantiationService.createInstance(MainThreadLanguageFeatures));