1 files changed, 71 insertions, 0 deletions
diff --git a/testing/web-platform/tests/dom/observable/tentative/observable-event-target.any.js b/testing/web-platform/tests/dom/observable/tentative/observable-event-target.any.js
new file mode 100644
index 0000000000..0f7ace2acc
--- /dev/null
+++ b/testing/web-platform/tests/dom/observable/tentative/observable-event-target.any.js
@@ -0,0 +1,71 @@
+test(() => {
+  const target = new EventTarget();
+  assert_implements(target.on, "The EventTarget interface has an `on` method");
+  assert_equals(typeof target.on, "function",
+      "EventTarget should have the on method");
+
+  const testEvents = target.on("test");
+  assert_true(testEvents instanceof Observable,
+      "EventTarget.on returns an Observable");
+
+  const results = [];
+  testEvents.subscribe({
+    next: value => results.push(value),
+    error: () => results.push("error"),
+    complete: () => results.push("complete"),
+  });
+
+  assert_array_equals(results, [],
+      "Observable does not emit events until event is fired");
+
+  const event = new Event("test");
+  target.dispatchEvent(event);
+  assert_array_equals(results, [event]);
+
+  target.dispatchEvent(event);
+  assert_array_equals(results, [event, event]);
+}, "EventTarget.on() returns an Observable");
+
+test(() => {
+  const target = new EventTarget();
+  const testEvents = target.on("test");
+  const ac = new AbortController();
+  const results = [];
+  testEvents.subscribe({
+    next: (value) => results.push(value),
+    error: () => results.push('error'),
+    complete: () => results.complete('complete'),
+  }, { signal: ac.signal });
+
+  assert_array_equals(results, [],
+      "Observable does not emit events until event is fired");
+
+  const event1 = new Event("test");
+  const event2 = new Event("test");
+  const event3 = new Event("test");
+  target.dispatchEvent(event1);
+  target.dispatchEvent(event2);
+
+  assert_array_equals(results, [event1, event2]);
+
+  ac.abort();
+  target.dispatchEvent(event3);
+
+  assert_array_equals(results, [event1, event2],
+      "Aborting the subscription removes the event listener and stops the " +
+      "emission of events");
+}, "Aborting the subscription should stop the emission of events");
+
+test(() => {
+  const target = new EventTarget();
+  const testEvents = target.on("test");
+  const results = [];
+  testEvents.subscribe(e => results.push(e));
+  testEvents.subscribe(e => results.push(e));
+
+  const event1 = new Event("test");
+  const event2 = new Event("test");
+  target.dispatchEvent(event1);
+  target.dispatchEvent(event2);
+  assert_array_equals(results, [event1, event1, event2, event2]);
+}, "EventTarget Observables can multicast subscriptions for event handling");