1 files changed, 93 insertions, 0 deletions
diff --git a/testing/web-platform/tests/compute-pressure/compute_pressure_basic.https.any.js b/testing/web-platform/tests/compute-pressure/compute_pressure_basic.https.any.js
new file mode 100644
index 0000000000..15d572bd8e
--- /dev/null
+++ b/testing/web-platform/tests/compute-pressure/compute_pressure_basic.https.any.js
@@ -0,0 +1,93 @@
+// META: timeout=long
+// META: script=/resources/test-only-api.js
+// META: script=resources/pressure-helpers.js
+// META: global=window,dedicatedworker,sharedworker
+
+'use strict';
+
+pressure_test((t, mockPressureService) => {
+  const observer = new PressureObserver(() => {
+    assert_unreached('The observer callback should not be called');
+  });
+
+  mockPressureService.setExpectedFailure(
+      new DOMException('', 'NotSupportedError'));
+  return promise_rejects_dom(t, 'NotSupportedError', observer.observe('cpu'));
+}, 'Return NotSupportedError when calling observer()');
+
+pressure_test(async (t, mockPressureService) => {
+  const changes = await new Promise(resolve => {
+    const observer = new PressureObserver(resolve);
+    t.add_cleanup(() => observer.disconnect());
+    observer.observe('cpu');
+    mockPressureService.setPressureUpdate('cpu', 'critical');
+    mockPressureService.startPlatformCollector(/*sampleInterval=*/ 200);
+  });
+  assert_true(changes.length === 1);
+  assert_equals(changes[0].state, 'critical');
+  assert_equals(changes[0].source, 'cpu');
+  assert_equals(typeof changes[0].time, 'number');
+}, 'Basic functionality test');
+
+pressure_test((t, mockPressureService) => {
+  const observer = new PressureObserver(() => {
+    assert_unreached('The observer callback should not be called');
+  });
+
+  const promise = observer.observe('cpu');
+  observer.unobserve('cpu');
+  mockPressureService.setPressureUpdate('cpu', 'critical');
+  mockPressureService.startPlatformCollector(/*sampleInterval=*/ 200);
+
+  return promise_rejects_dom(t, 'AbortError', promise);
+}, 'Removing observer before observe() resolves works');
+
+pressure_test(async (t, mockPressureService) => {
+  const callbackPromises = [];
+  const observePromises = [];
+
+  for (let i = 0; i < 2; i++) {
+    callbackPromises.push(new Promise(resolve => {
+      const observer = new PressureObserver(resolve);
+      t.add_cleanup(() => observer.disconnect());
+      observePromises.push(observer.observe('cpu'));
+    }));
+  }
+
+  await Promise.all(observePromises);
+
+  mockPressureService.setPressureUpdate('cpu', 'critical');
+  mockPressureService.startPlatformCollector(/*sampleInterval=*/ 200);
+
+  return Promise.all(callbackPromises);
+}, 'Calling observe() multiple times works');
+
+pressure_test(async (t, mockPressureService) => {
+  const observer1_changes = [];
+  await new Promise(resolve => {
+    const observer1 = new PressureObserver(changes => {
+      observer1_changes.push(changes);
+      resolve();
+    });
+    t.add_cleanup(() => observer1.disconnect());
+    observer1.observe('cpu');
+    mockPressureService.setPressureUpdate('cpu', 'critical');
+    mockPressureService.startPlatformCollector(/*sampleInterval=*/ 200);
+  });
+  assert_true(observer1_changes.length === 1);
+  assert_equals(observer1_changes[0][0].source, 'cpu');
+  assert_equals(observer1_changes[0][0].state, 'critical');
+
+  const observer2_changes = [];
+  await new Promise(resolve => {
+    const observer2 = new PressureObserver(changes => {
+      observer2_changes.push(changes);
+      resolve();
+    });
+    t.add_cleanup(() => observer2.disconnect());
+    observer2.observe('cpu');
+  });
+  assert_true(observer2_changes.length === 1);
+  assert_equals(observer2_changes[0][0].source, 'cpu');
+  assert_equals(observer2_changes[0][0].state, 'critical');
+}, 'Starting a new observer after an observer has started works');