diff --git a/polygerrit-ui/app/utils/async-util_test.js b/polygerrit-ui/app/utils/async-util_test.js
deleted file mode 100644
index df29e97..0000000
--- a/polygerrit-ui/app/utils/async-util_test.js
+++ /dev/null
@@ -1,46 +0,0 @@
-/**
- * @license
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import '../test/common-test-setup-karma.js';
-import {asyncForeach} from './async-util.js';
-
-suite('async-util tests', () => {
-  test('loops over each item', () => {
-    const fn = sinon.stub().returns(Promise.resolve());
-    return asyncForeach([1, 2, 3], fn)
-        .then(() => {
-          assert.isTrue(fn.calledThrice);
-          assert.equal(fn.getCall(0).args[0], 1);
-          assert.equal(fn.getCall(1).args[0], 2);
-          assert.equal(fn.getCall(2).args[0], 3);
-        });
-  });
-
-  test('halts on stop condition', () => {
-    const stub = sinon.stub();
-    const fn = (e, stop) => {
-      stub(e);
-      stop();
-      return Promise.resolve();
-    };
-    return asyncForeach([1, 2, 3], fn)
-        .then(() => {
-          assert.isTrue(stub.calledOnce);
-          assert.equal(stub.lastCall.args[0], 1);
-        });
-  });
-});
diff --git a/polygerrit-ui/app/utils/async-util_test.ts b/polygerrit-ui/app/utils/async-util_test.ts
new file mode 100644
index 0000000..5c8f610
--- /dev/null
+++ b/polygerrit-ui/app/utils/async-util_test.ts
@@ -0,0 +1,46 @@
+/**
+ * @license
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import '../test/common-test-setup-karma';
+import {asyncForeach} from './async-util';
+
+suite('async-util tests', () => {
+  test('loops over each item', async () => {
+    const fn = sinon.stub().resolves();
+
+    await asyncForeach([1, 2, 3], fn);
+
+    assert.isTrue(fn.calledThrice);
+    assert.equal(fn.firstCall.firstArg, 1);
+    assert.equal(fn.secondCall.firstArg, 2);
+    assert.equal(fn.thirdCall.firstArg, 3);
+  });
+
+  test('halts on stop condition', async () => {
+    const stub = sinon.stub();
+    const fn = (item: number, stopCallback: () => void) => {
+      stub(item);
+      stopCallback();
+      return Promise.resolve();
+    };
+
+    await asyncForeach([1, 2, 3], fn);
+
+    assert.isTrue(stub.calledOnce);
+    assert.equal(stub.lastCall.firstArg, 1);
+  });
+});