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"use strict";
test(() => {
const target = new EventTarget();
const event = new Event("foo", { bubbles: true, cancelable: false });
let callCount = 0;
function listener(e) {
assert_equals(e, event);
++callCount;
}
target.addEventListener("foo", listener);
target.dispatchEvent(event);
assert_equals(callCount, 1);
target.dispatchEvent(event);
assert_equals(callCount, 2);
target.removeEventListener("foo", listener);
target.dispatchEvent(event);
assert_equals(callCount, 2);
}, "A constructed EventTarget can be used as expected");
test(() => {
class NicerEventTarget extends EventTarget {
on(...args) {
this.addEventListener(...args);
}
off(...args) {
this.removeEventListener(...args);
}
dispatch(type, detail) {
this.dispatchEvent(new CustomEvent(type, { detail }));
}
}
const target = new NicerEventTarget();
const event = new Event("foo", { bubbles: true, cancelable: false });
const detail = "some data";
let callCount = 0;
function listener(e) {
assert_equals(e.detail, detail);
++callCount;
}
target.on("foo", listener);
target.dispatch("foo", detail);
assert_equals(callCount, 1);
target.dispatch("foo", detail);
assert_equals(callCount, 2);
target.off("foo", listener);
target.dispatch("foo", detail);
assert_equals(callCount, 2);
}, "EventTarget can be subclassed");
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