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Test Info:
- Manifest: dom/promise/tests/unit/xpcshell.toml
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const { setTimeout } = ChromeUtils.importESModule(
"resource://gre/modules/Timer.sys.mjs"
);
const { PromiseTestUtils } = ChromeUtils.importESModule(
);
// Prevent test failures due to the unhandled rejections in this test file.
PromiseTestUtils.disableUncaughtRejectionObserverForSelfTest();
add_task(async function test_globals() {
Assert.notEqual(
PromiseDebugging,
undefined,
"PromiseDebugging is available."
);
});
add_task(async function test_promiseID() {
let p1 = new Promise(() => {});
let p2 = new Promise(() => {});
let p3 = p2.catch(null);
let promise = [p1, p2, p3];
let identifiers = promise.map(PromiseDebugging.getPromiseID);
info("Identifiers: " + JSON.stringify(identifiers));
let idSet = new Set(identifiers);
Assert.equal(
idSet.size,
identifiers.length,
"PromiseDebugging.getPromiseID returns a distinct id per promise"
);
let identifiers2 = promise.map(PromiseDebugging.getPromiseID);
Assert.equal(
JSON.stringify(identifiers),
JSON.stringify(identifiers2),
"Successive calls to PromiseDebugging.getPromiseID return the same id for the same promise"
);
});
add_task(async function test_observe_uncaught() {
// The names of Promise instances
let names = new Map();
// The results for UncaughtPromiseObserver callbacks.
let CallbackResults = function (name) {
this.name = name;
this.expected = new Set();
this.observed = new Set();
this.blocker = new Promise(resolve => (this.resolve = resolve));
};
CallbackResults.prototype = {
observe(promise) {
info(this.name + " observing Promise " + names.get(promise));
Assert.equal(
PromiseDebugging.getState(promise).state,
"rejected",
this.name + " observed a rejected Promise"
);
if (!this.expected.has(promise)) {
Assert.ok(
false,
this.name +
" observed a Promise that it expected to observe, " +
names.get(promise) +
" (" +
PromiseDebugging.getPromiseID(promise) +
", " +
PromiseDebugging.getAllocationStack(promise) +
")"
);
}
Assert.ok(
this.expected.delete(promise),
this.name +
" observed a Promise that it expected to observe, " +
names.get(promise) +
" (" +
PromiseDebugging.getPromiseID(promise) +
")"
);
Assert.ok(
!this.observed.has(promise),
this.name + " observed a Promise that it has not observed yet"
);
this.observed.add(promise);
if (this.expected.size == 0) {
this.resolve();
} else {
info(
this.name +
" is still waiting for " +
this.expected.size +
" observations:"
);
info(
JSON.stringify(Array.from(this.expected.values(), x => names.get(x)))
);
}
},
};
let onLeftUncaught = new CallbackResults("onLeftUncaught");
let onConsumed = new CallbackResults("onConsumed");
let observer = {
onLeftUncaught(promise) {
onLeftUncaught.observe(promise);
},
onConsumed(promise) {
onConsumed.observe(promise);
},
};
let resolveLater = function (delay = 20) {
// eslint-disable-next-line mozilla/no-arbitrary-setTimeout
return new Promise(resolve => setTimeout(resolve, delay));
};
let rejectLater = function (delay = 20) {
// eslint-disable-next-line mozilla/no-arbitrary-setTimeout
return new Promise((resolve, reject) => setTimeout(reject, delay));
};
let makeSamples = function* () {
yield {
promise: Promise.resolve(0),
name: "Promise.resolve",
};
yield {
promise: Promise.resolve(resolve => resolve(0)),
name: "Resolution callback",
};
yield {
promise: Promise.resolve(0).catch(null),
name: "`catch(null)`",
};
yield {
promise: Promise.reject(0).catch(() => {}),
name: "Reject and catch immediately",
};
yield {
promise: resolveLater(),
name: "Resolve later",
};
yield {
promise: Promise.reject("Simple rejection"),
leftUncaught: true,
consumed: false,
name: "Promise.reject",
};
// Reject a promise now, consume it later.
let p = Promise.reject("Reject now, consume later");
// eslint-disable-next-line mozilla/no-arbitrary-setTimeout
setTimeout(
() =>
p.catch(() => {
info("Consumed promise");
}),
200
);
yield {
promise: p,
leftUncaught: true,
consumed: true,
name: "Reject now, consume later",
};
yield {
promise: Promise.all([Promise.resolve("Promise.all"), rejectLater()]),
leftUncaught: true,
name: "Rejecting through Promise.all",
};
yield {
promise: Promise.race([resolveLater(500), Promise.reject()]),
leftUncaught: true, // The rejection wins the race.
name: "Rejecting through Promise.race",
};
yield {
promise: Promise.race([Promise.resolve(), rejectLater(500)]),
leftUncaught: false, // The resolution wins the race.
name: "Resolving through Promise.race",
};
let boom = new Error("`throw` in the constructor");
yield {
promise: new Promise(() => {
throw boom;
}),
leftUncaught: true,
name: "Throwing in the constructor",
};
let rejection = Promise.reject("`reject` during resolution");
yield {
promise: rejection,
leftUncaught: false,
consumed: false, // `rejection` is consumed immediately (see below)
name: "Promise.reject, again",
};
yield {
promise: new Promise(resolve => resolve(rejection)),
leftUncaught: true,
consumed: false,
name: "Resolving with a rejected promise",
};
yield {
promise: Promise.resolve(0).then(() => rejection),
leftUncaught: true,
consumed: false,
name: "Returning a rejected promise from success handler",
};
yield {
promise: Promise.resolve(0).then(() => {
throw new Error();
}),
leftUncaught: true,
consumed: false,
name: "Throwing during the call to the success callback",
};
};
let samples = [];
for (let s of makeSamples()) {
samples.push(s);
info(
"Promise '" +
s.name +
"' has id " +
PromiseDebugging.getPromiseID(s.promise)
);
}
PromiseDebugging.addUncaughtRejectionObserver(observer);
for (let s of samples) {
names.set(s.promise, s.name);
if (s.leftUncaught || false) {
onLeftUncaught.expected.add(s.promise);
}
if (s.consumed || false) {
onConsumed.expected.add(s.promise);
}
}
info("Test setup, waiting for callbacks.");
await onLeftUncaught.blocker;
info("All calls to onLeftUncaught are complete.");
if (onConsumed.expected.size != 0) {
info("onConsumed is still waiting for the following Promise:");
info(
JSON.stringify(
Array.from(onConsumed.expected.values(), x => names.get(x))
)
);
await onConsumed.blocker;
}
info("All calls to onConsumed are complete.");
let removed = PromiseDebugging.removeUncaughtRejectionObserver(observer);
Assert.ok(removed, "removeUncaughtRejectionObserver succeeded");
removed = PromiseDebugging.removeUncaughtRejectionObserver(observer);
Assert.ok(
!removed,
"second call to removeUncaughtRejectionObserver didn't remove anything"
);
});
add_task(async function test_uninstall_observer() {
let Observer = function () {
this.blocker = new Promise(resolve => (this.resolve = resolve));
this.active = true;
};
Observer.prototype = {
set active(x) {
this._active = x;
if (x) {
PromiseDebugging.addUncaughtRejectionObserver(this);
} else {
PromiseDebugging.removeUncaughtRejectionObserver(this);
}
},
onLeftUncaught() {
Assert.ok(this._active, "This observer is active.");
this.resolve();
},
onConsumed() {
Assert.ok(false, "We should not consume any Promise.");
},
};
info("Adding an observer.");
let deactivate = new Observer();
Promise.reject("I am an uncaught rejection.");
await deactivate.blocker;
Assert.ok(true, "The observer has observed an uncaught Promise.");
deactivate.active = false;
info(
"Removing the observer, it should not observe any further uncaught Promise."
);
info(
"Rejecting a Promise and waiting a little to give a chance to observers."
);
let wait = new Observer();
Promise.reject("I am another uncaught rejection.");
await wait.blocker;
// eslint-disable-next-line mozilla/no-arbitrary-setTimeout
await new Promise(resolve => setTimeout(resolve, 100));
// Normally, `deactivate` should not be notified of the uncaught rejection.
wait.active = false;
});