1 files changed, 19 insertions, 0 deletions
diff --git a/testing/web-platform/tests/compute-pressure/compute_pressure_observe_idempotent.https.any.js b/testing/web-platform/tests/compute-pressure/compute_pressure_observe_idempotent.https.any.js
new file mode 100644
index 0000000000..9fcbb49814
--- /dev/null
+++ b/testing/web-platform/tests/compute-pressure/compute_pressure_observe_idempotent.https.any.js
@@ -0,0 +1,19 @@
+// META: script=/resources/test-only-api.js
+// META: script=resources/pressure-helpers.js
+// META: global=window,dedicatedworker,sharedworker
+
+'use strict';
+
+pressure_test(async (t, mockPressureService) => {
+  const update = await new Promise((resolve, reject) => {
+    const observer = new PressureObserver(resolve);
+    t.add_cleanup(() => observer.disconnect());
+    observer.observe('cpu').catch(reject);
+    observer.observe('cpu').catch(reject);
+    observer.observe('cpu').catch(reject);
+    mockPressureService.setPressureUpdate('cpu', 'critical');
+    mockPressureService.startPlatformCollector(/*sampleInterval=*/ 200);
+  });
+
+  assert_equals(update[0].state, 'critical');
+}, 'PressureObserver.observe() is idempotent');