Fix unhandled promise rejection in abortable

src/abortable.test.ts

@@ -0,0 +1,75 @@
+import AbortController from 'node-abort-controller';
+import {abortable} from './abortable';
+import {nextTick} from './utils/nextTick';
+
+test('abortable endless promise', async () => {
+  const abortController = new AbortController();
+  const signal = abortController.signal;
+  signal.addEventListener = jest.fn(signal.addEventListener);
+  signal.removeEventListener = jest.fn(signal.removeEventListener);
+
+  let result: PromiseSettledResult<void> | undefined;
+
+  abortable(
+    signal,
+    new Promise<void>(() => {}),
+  ).then(
+    value => {
+      result = {status: 'fulfilled', value};
+    },
+    reason => {
+      result = {status: 'rejected', reason};
+    },
+  );
+
+  await nextTick();
+
+  expect(result).toBeUndefined();
+
+  abortController.abort();
+
+  await nextTick();
+
+  expect(result).toMatchObject({
+    status: 'rejected',
+    reason: {name: 'AbortError'},
+  });
+
+  expect(signal.addEventListener).toHaveBeenCalledTimes(1);
+  expect(signal.removeEventListener).toHaveBeenCalledTimes(1);
+});
+
+test('abort before reject', async () => {
+  const abortController = new AbortController();
+  const signal = abortController.signal;
+  signal.addEventListener = jest.fn(signal.addEventListener);
+  signal.removeEventListener = jest.fn(signal.removeEventListener);
+
+  abortController.abort();
+
+  let result: PromiseSettledResult<void> | undefined;
+
+  abortable(
+    signal,
+    new Promise<void>((resolve, reject) => {
+      reject('test');
+    }),
+  ).then(
+    value => {
+      result = {status: 'fulfilled', value};
+    },
+    reason => {
+      result = {status: 'rejected', reason};
+    },
+  );
+
+  await nextTick();
+
+  expect(result).toMatchObject({
+    status: 'rejected',
+    reason: {name: 'AbortError'},
+  });
+
+  expect(signal.addEventListener).toHaveBeenCalledTimes(0);
+  expect(signal.removeEventListener).toHaveBeenCalledTimes(0);
+});

src/abortable.ts

@@ -11,6 +11,12 @@ export function abortable<T>(
   signal: AbortSignal,
   promise: PromiseLike<T>,
 ): Promise<T> {
+  if (signal.aborted) {
+    // prevent unhandled rejection
+    const noop = () => {};
+    promise.then(noop, noop);
+  }
+
   return execute<T>(signal, (resolve, reject) => {
     promise.then(resolve, reject);