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Test Info:
- This WPT test may be referenced by the following Test IDs:
- /html/webappapis/microtask-queuing/queue-microtask.any.html - WPT Dashboard Interop Dashboard
- /html/webappapis/microtask-queuing/queue-microtask.any.serviceworker.html - WPT Dashboard Interop Dashboard
- /html/webappapis/microtask-queuing/queue-microtask.any.sharedworker.html - WPT Dashboard Interop Dashboard
- /html/webappapis/microtask-queuing/queue-microtask.any.worker.html - WPT Dashboard Interop Dashboard
// META: global=window,worker
"use strict";
test(() => {
assert_equals(typeof queueMicrotask, "function");
}, "It exists and is a function");
test(() => {
assert_throws_js(TypeError, () => queueMicrotask(), "no argument");
assert_throws_js(TypeError, () => queueMicrotask(undefined), "undefined");
assert_throws_js(TypeError, () => queueMicrotask(null), "null");
assert_throws_js(TypeError, () => queueMicrotask(0), "0");
assert_throws_js(TypeError, () => queueMicrotask({ handleEvent() { } }), "an event handler object");
assert_throws_js(TypeError, () => queueMicrotask("window.x = 5;"), "a string");
}, "It throws when given non-functions");
async_test(t => {
let called = false;
queueMicrotask(t.step_func_done(() => {
called = true;
}));
assert_false(called);
}, "It calls the callback asynchronously");
async_test(t => {
queueMicrotask(t.step_func_done(function () { // note: intentionally not an arrow function
assert_array_equals(arguments, []);
}), "x", "y");
}, "It does not pass any arguments");
async_test(t => {
const happenings = [];
Promise.resolve().then(() => happenings.push("a"));
queueMicrotask(() => happenings.push("b"));
Promise.reject().catch(() => happenings.push("c"));
queueMicrotask(t.step_func_done(() => {
assert_array_equals(happenings, ["a", "b", "c"]);
}));
}, "It interleaves with promises as expected");