1 files changed, 22 insertions, 0 deletions
diff --git a/testing/web-platform/tests/cookie-store/cookieStore_event_overwrite.https.window.js b/testing/web-platform/tests/cookie-store/cookieStore_event_overwrite.https.window.js
new file mode 100644
index 0000000000..3acffea41c
--- /dev/null
+++ b/testing/web-platform/tests/cookie-store/cookieStore_event_overwrite.https.window.js
@@ -0,0 +1,22 @@
+'use strict';
+
+promise_test(async testCase => {
+  await cookieStore.set('cookie-name', 'cookie-value');
+  testCase.add_cleanup(async () => {
+    await cookieStore.delete('cookie-name');
+  });
+
+  const eventPromise = new Promise((resolve) => {
+    cookieStore.onchange = resolve;
+  });
+
+  await cookieStore.set('cookie-name', 'new-cookie-value');
+
+  const event = await eventPromise;
+  assert_true(event instanceof CookieChangeEvent);
+  assert_equals(event.type, 'change');
+  assert_equals(event.changed.length, 1);
+  assert_equals(event.changed[0].name, 'cookie-name');
+  assert_equals(event.changed[0].value, 'new-cookie-value');
+  assert_equals(event.deleted.length, 0);
+}, 'cookieStore fires change event for cookie overwritten by cookieStore.set()');