fix: ensure that we wait for processes to shutdown

src/createSpawn.test.ts

@@ -19,3 +19,33 @@ it('rejects if process produces an error', async () => {
 
   await expect(spawn`does-not-exist`).rejects.toThrowError('Program exited with code 127.');
 });
+
+const TIMEOUT = 100;
+
+it('terminates spawned process when it receives abort signal', async () => {
+  const abortController = new AbortController();
+
+  const spawn = createSpawn('foo', abortController.signal);
+
+  setTimeout(() => {
+    void abortController.abort();
+  }, 50);
+
+  await spawn`sleep 10`;
+}, TIMEOUT);
+
+it('waits for termination', async () => {
+  const abortController = new AbortController();
+
+  const spawn = createSpawn('foo', abortController.signal);
+
+  setTimeout(() => {
+    void abortController.abort();
+  }, 50);
+
+  const start = Date.now();
+
+  await spawn`( trap '' TERM; exec sleep 0.1 )`;
+
+  expect(Date.now() - start).toBeGreaterThan(100);
+}, TIMEOUT * 2);

src/createSpawn.ts

@@ -61,6 +61,10 @@ export const createSpawn = (taskId: string, triggerSignal: AbortSignal | null) =
       return result;
     }
 
+    if (triggerSignal?.aborted) {
+      return result;
+    }
+
     log.error('task %s exited with an error', taskId);
 
     throw new Error('Program exited with code ' + result.exitCode + '.');