1 files changed, 19 insertions, 0 deletions
diff --git a/testing/web-platform/tests/compute-pressure/compute_pressure_observe_unobserve_failure.https.any.js b/testing/web-platform/tests/compute-pressure/compute_pressure_observe_unobserve_failure.https.any.js
new file mode 100644
index 0000000000..8eafeb356d
--- /dev/null
+++ b/testing/web-platform/tests/compute-pressure/compute_pressure_observe_unobserve_failure.https.any.js
@@ -0,0 +1,19 @@
+// META: global=window,dedicatedworker,sharedworker
+
+'use strict';
+
+promise_test(async t => {
+  const observer =
+      new PressureObserver(t.unreached_func('oops should not end up here'));
+  t.add_cleanup(() => observer.disconnect());
+  await promise_rejects_js(t, TypeError, observer.observe('random'));
+}, 'PressureObserver.observe() requires a valid source');
+
+test(t => {
+  const observer =
+      new PressureObserver(t.unreached_func('oops should not end up here'));
+  t.add_cleanup(() => observer.disconnect());
+  assert_throws_js(TypeError, () => {
+    observer.unobserve('random');
+  });
+}, 'PressureObserver.unobserve() requires a valid source');