fix: memory leak in test results

src/vs/workbench/contrib/testing/browser/testResultsView/testResultsViewContent.ts

@@ -250,7 +250,7 @@ export class TestResultsViewContent extends Disposable {
 
 	public fillBody(containerElement: HTMLElement): void {
 		const initialSpitWidth = TestResultsViewContent.lastSplitWidth;
-		this.splitView = new SplitView(containerElement, { orientation: Orientation.HORIZONTAL });
+		this.splitView = this._register(new SplitView(containerElement, { orientation: Orientation.HORIZONTAL }));
 
 		const { historyVisible, showRevealLocationOnMessages } = this.options;
 		const isInPeekView = this.editor !== undefined;

src/vs/workbench/contrib/testing/common/testResultService.ts

@@ -76,7 +76,7 @@ export class TestResultService extends Disposable implements ITestResultService
 	declare _serviceBrand: undefined;
 	private changeResultEmitter = this._register(new Emitter<ResultChangeEvent>());
 	private _results: ITestResult[] = [];
-	private readonly _resultsDisposables: DisposableStore[] = [];
+	private readonly _resultsDisposables = new Map<ITestResult, DisposableStore>();
 	private testChangeEmitter = this._register(new Emitter<TestResultItemChange>());
 	private insertOrderCounter = 0;
 
@@ -115,7 +115,7 @@ export class TestResultService extends Disposable implements ITestResultService
 		@ITelemetryService private readonly telemetryService: ITelemetryService,
 	) {
 		super();
-		this._register(toDisposable(() => dispose(this._resultsDisposables)));
+		this._register(toDisposable(() => dispose(this._resultsDisposables.values())));
 		this.isRunning = TestingContextKeys.isRunning.bindTo(contextKeyService);
 		this.hasAnyResults = TestingContextKeys.hasAnyResults.bindTo(contextKeyService);
 	}
@@ -172,6 +172,14 @@ export class TestResultService extends Disposable implements ITestResultService
 	 * @inheritdoc
 	 */
 	public push<T extends ITestResult>(result: T): T {
+		if (result instanceof LiveTestResult) {
+			const ds = new DisposableStore();
+			this._resultsDisposables.set(result, ds);
+			ds.add(result);
+			ds.add(result.onComplete(() => this.onComplete(result)));
+			ds.add(result.onChange(this.testChangeEmitter.fire, this.testChangeEmitter));
+		}
+
 		if (result.completedAt === undefined) {
 			this.results.unshift(result);
 		} else {
@@ -182,17 +190,12 @@ export class TestResultService extends Disposable implements ITestResultService
 
 		this.hasAnyResults.set(true);
 		if (this.results.length > RETAIN_MAX_RESULTS) {
-			this.results.pop();
-			this._resultsDisposables.pop()?.dispose();
+			const removed = this.results.pop()!;
+			this._resultsDisposables.get(removed)?.dispose();
+			this._resultsDisposables.delete(removed);
 		}
 
-		const ds = new DisposableStore();
-		this._resultsDisposables.push(ds);
-
 		if (result instanceof LiveTestResult) {
-			ds.add(result);
-			ds.add(result.onComplete(() => this.onComplete(result)));
-			ds.add(result.onChange(this.testChangeEmitter.fire, this.testChangeEmitter));
 			this.isRunning.set(true);
 			this.changeResultEmitter.fire({ started: result });
 		} else {
@@ -237,6 +240,10 @@ export class TestResultService extends Disposable implements ITestResultService
 		}
 
 		this._results = keep;
+		for (const result of removed) {
+			this._resultsDisposables.get(result)?.dispose();
+			this._resultsDisposables.delete(result);
+		}
 		this.persistScheduler.schedule();
 		if (keep.length === 0) {
 			this.hasAnyResults.set(false);

src/vs/workbench/contrib/testing/test/common/testResultService.test.ts

@@ -44,6 +44,8 @@ suite('Workbench - Test Results Service', () => {
 	let insertCounter = 0;
 
 	class TestLiveTestResult extends LiveTestResult {
+		public disposed = false;
+
 		constructor(
 			id: string,
 			persist: boolean,
@@ -56,6 +58,11 @@ suite('Workbench - Test Results Service', () => {
 		public setAllToStatePublic(state: TestResultState, taskId: string, when: (task: ITestTaskState, item: TestResultItem) => boolean) {
 			this.setAllToState(state, taskId, when);
 		}
+
+		public override dispose(): void {
+			this.disposed = true;
+			super.dispose();
+		}
 	}
 
 	const ds = ensureNoDisposablesAreLeakedInTestSuite();
@@ -272,6 +279,7 @@ suite('Workbench - Test Results Service', () => {
 			results.clear();
 
 			assert.deepStrictEqual(results.results, [r2]);
+			assert.strictEqual(r.disposed, true);
 		});
 
 		test('keeps ongoing tests on top, restored order when done', async () => {
@@ -331,6 +339,19 @@ suite('Workbench - Test Results Service', () => {
 			results.push(hydrated2);
 			assert.deepStrictEqual(results.results, [r, hydrated1, hydrated2]);
 		});
+
+		test('disposes a completed result that is immediately evicted', async () => {
+			const newerCompletedAt = Date.now() + 1000;
+			for (let i = 0; i < 128; i++) {
+				results.push(await makeHydrated(newerCompletedAt + i));
+			}
+
+			const older = new TestLiveTestResult('older', false, defaultOpts([]));
+			older.markComplete();
+			results.push(older);
+
+			assert.deepStrictEqual({ retained: results.results.includes(older), disposed: older.disposed }, { retained: false, disposed: true });
+		});
 	});
 
 	test('resultItemParents', function () {