1 files changed, 12 insertions, 0 deletions
diff --git a/testing/mochitest/tests/browser/browser_uncaught_rejection_expected.js b/testing/mochitest/tests/browser/browser_uncaught_rejection_expected.js
new file mode 100644
index 0000000000..2ee9f23d79
--- /dev/null
+++ b/testing/mochitest/tests/browser/browser_uncaught_rejection_expected.js
@@ -0,0 +1,12 @@
+const { PromiseTestUtils } = ChromeUtils.importESModule(
+  "resource://testing-common/PromiseTestUtils.sys.mjs"
+);
+PromiseTestUtils.allowMatchingRejectionsGlobally(/Allowed rejection./);
+PromiseTestUtils.expectUncaughtRejection(/Promise rejection./);
+PromiseTestUtils.expectUncaughtRejection(/Promise rejection./);
+
+function test() {
+  Promise.reject(new Error("Promise rejection."));
+  Promise.reject(new Error("Promise rejection."));
+  Promise.reject(new Error("Allowed rejection."));
+}