1 files changed, 32 insertions, 0 deletions
diff --git a/testing/web-platform/tests/fetch/stale-while-revalidate/fetch.any.js b/testing/web-platform/tests/fetch/stale-while-revalidate/fetch.any.js
new file mode 100644
index 0000000000..3682b9d2c3
--- /dev/null
+++ b/testing/web-platform/tests/fetch/stale-while-revalidate/fetch.any.js
@@ -0,0 +1,32 @@
+// META: global=window,worker
+// META: title=Tests Stale While Revalidate is executed for fetch API
+// META: script=/common/utils.js
+
+function wait25ms(test) {
+  return new Promise(resolve => {
+    test.step_timeout(() => {
+      resolve();
+    }, 25);
+  });
+}
+
+promise_test(async (test) => {
+  var request_token = token();
+
+  const response = await fetch(`resources/stale-script.py?token=` + request_token);
+  // Wait until resource is completely fetched to allow caching before next fetch.
+  const body = await response.text();
+  const response2 = await fetch(`resources/stale-script.py?token=` + request_token);
+
+  assert_equals(response.headers.get('Unique-Id'), response2.headers.get('Unique-Id'));
+  const body2 = await response2.text();
+  assert_equals(body, body2);
+
+  while(true) {
+    const revalidation_check = await fetch(`resources/stale-script.py?query&token=` + request_token);
+    if (revalidation_check.headers.get('Count') == '2') {
+      break;
+    }
+    await wait25ms(test);
+  }
+}, 'Second fetch returns same response');