Make touch and wheel events without non-passive listeners uncancelable.

vinhill · moz-wptsync-bot · commit dedf2fa3e7b0 · 2025-04-29T06:39:41.000+01:00
According to the spec https://w3c.github.io/touch-events/#cancelability, the touchstart, touchend and touchmove events should be uncancelable if there are no non-passive listeners. According to https://w3c.github.io/uievents/#cancelability-of-wheel-events, this also holds for wheel events. Differential Revision: https://phabricator.services.mozilla.com/D218199 bugzilla-url: https://bugzilla.mozilla.org/show_bug.cgi?id=1356293 gecko-commit: c57d28db5a72ffce969424f9302d5d315d148d75 gecko-reviewers: dom-core, edgar
diff --git a/dom/events/non-cancelable-when-passive/generic-events-stay-cancelable.html b/dom/events/non-cancelable-when-passive/generic-events-stay-cancelable.html
@@ -0,0 +1,14 @@
+<!doctype html>
+<meta charset=utf-8>
+<title></title>
+<script src=/resources/testharness.js></script>
+<script src=/resources/testharnessreport.js></script>
+<script>
+async_test((t) => {
+    const et = new EventTarget();
+    et.addEventListener('test', t.step_func_done((e) => {
+        assert_true(e.cancelable);
+    }), {passive: true});
+    et.dispatchEvent(new Event('test', {cancelable: true}));
+}, "A generic event with only passive listeners remains cancelable");
+</script>
