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Test Info: Warnings
- This test has a WPT meta file that expects 5 subtest issues.
- This WPT test may be referenced by the following Test IDs:
- /dom/observable/tentative/observable-last.any.html - WPT Dashboard Interop Dashboard
- /dom/observable/tentative/observable-last.any.worker.html - WPT Dashboard Interop Dashboard
promise_test(async () => {
const source = new Observable(subscriber => {
// Never exposed to the `last()` promise.
subscriber.next(1);
subscriber.next(2);
subscriber.complete();
});
const value = await source.last();
assert_equals(value, 2);
}, "last(): Promise resolves to last value");
promise_test(async (t) => {
const error = new Error("error from source");
const source = new Observable(subscriber => {
subscriber.error(error);
});
return promise_rejects_exactly(t, error, source.last());
}, "last(): Promise rejects with emitted error");
promise_test(async (t) => {
const source = new Observable(subscriber => {
subscriber.complete();
});
return promise_rejects_js(t, RangeError, source.last());
}, "last(): Promise rejects with RangeError when source Observable " +
"completes without emitting any values");
promise_test(async (t) => {
const source = new Observable(subscriber => {});
const controller = new AbortController();
const promise = source.last({ signal: controller.signal });
controller.abort();
return promise_rejects_dom(t, "AbortError", promise, "Promise rejects with a DOMException for abortion");
}, "last(): Aborting a signal rejects the Promise with an AbortError DOMException");
promise_test(async () => {
const results = [];
const source = new Observable(subscriber => {
results.push("source subscribe");
subscriber.addTeardown(() => results.push("source teardown"));
subscriber.signal.addEventListener("abort", () => results.push("source abort"));
results.push("before source next 1");
subscriber.next(1);
results.push("after source next 1");
results.push("before source complete");
subscriber.complete();
results.push("after source complete");
});
results.push("calling last");
const promise = source.last();
assert_array_equals(results, [
"calling last",
"source subscribe",
"before source next 1",
"after source next 1",
"before source complete",
"source abort",
"source teardown",
"after source complete",
], "Array values after last() is called");
const lastValue = await promise;
results.push(`last resolved with: ${lastValue}`);
assert_array_equals(results, [
"calling last",
"source subscribe",
"before source next 1",
"after source next 1",
"before source complete",
"source abort",
"source teardown",
"after source complete",
"last resolved with: 1",
], "Array values after Promise is awaited");
}, "last(): Lifecycle");