test: Fix flaky task-runner integration test (n8n-io#11302)

packages/cli/src/runners/task-runner-process.ts

@@ -23,10 +23,14 @@ export class TaskRunnerProcess {
 		return this.process?.pid;
 	}
 
+	/** Promise that resolves when the process has exited */
+	public get runPromise() {
+		return this._runPromise;
+	}
+
 	private process: ChildProcess | null = null;
 
-	/** Promise that resolves after the process has exited */
-	private runPromise: Promise<void> | null = null;
+	private _runPromise: Promise<void> | null = null;
 
 	private isShuttingDown = false;
 
@@ -97,7 +101,7 @@ export class TaskRunnerProcess {
 		} else {
 			this.killNode();
 		}
-		await this.runPromise;
+		await this._runPromise;
 
 		this.isShuttingDown = false;
 	}
@@ -128,7 +132,7 @@ export class TaskRunnerProcess {
 	}
 
 	private monitorProcess(taskRunnerProcess: ChildProcess) {
-		this.runPromise = new Promise((resolve) => {
+		this._runPromise = new Promise((resolve) => {
 			taskRunnerProcess.on('exit', (code) => {
 				this.onProcessExit(code, resolve);
 			});

packages/cli/test/integration/runners/task-runner-process.test.ts

@@ -88,15 +88,15 @@ describe('TaskRunnerProcess', () => {
 		// @ts-expect-error private property
 		runnerProcess.process?.kill('SIGKILL');
 
-		// Assert
-		// Wait until the runner is running again
-		await retryUntil(() => expect(runnerProcess.isRunning).toBeTruthy());
-		expect(runnerProcess.pid).not.toBe(processId);
+		// Wait until the runner has exited
+		await runnerProcess.runPromise;
 
+		// Assert
 		// Wait until the runner has connected again
 		await retryUntil(() => expect(getNumConnectedRunners()).toBe(1));
 		expect(getNumConnectedRunners()).toBe(1);
 		expect(getNumRegisteredRunners()).toBe(1);
+		expect(runnerProcess.pid).not.toBe(processId);
 	});
 
 	it('should launch runner directly if not using a launcher', async () => {