732 lines
21 KiB
JavaScript
732 lines
21 KiB
JavaScript
// META: global=window,worker,shadowrealm
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// META: script=../resources/rs-utils.js
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// META: script=../resources/test-utils.js
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// META: script=../resources/recording-streams.js
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'use strict';
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const error1 = new Error('error1');
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function assert_iter_result(iterResult, value, done, message) {
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const prefix = message === undefined ? '' : `${message} `;
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assert_equals(typeof iterResult, 'object', `${prefix}type is object`);
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assert_equals(Object.getPrototypeOf(iterResult), Object.prototype, `${prefix}[[Prototype]]`);
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assert_array_equals(Object.getOwnPropertyNames(iterResult).sort(), ['done', 'value'], `${prefix}property names`);
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assert_equals(iterResult.value, value, `${prefix}value`);
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assert_equals(iterResult.done, done, `${prefix}done`);
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}
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test(() => {
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const s = new ReadableStream();
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const it = s.values();
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const proto = Object.getPrototypeOf(it);
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const AsyncIteratorPrototype = Object.getPrototypeOf(Object.getPrototypeOf(async function* () {}).prototype);
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assert_equals(Object.getPrototypeOf(proto), AsyncIteratorPrototype, 'prototype should extend AsyncIteratorPrototype');
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const methods = ['next', 'return'].sort();
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assert_array_equals(Object.getOwnPropertyNames(proto).sort(), methods, 'should have all the correct methods');
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for (const m of methods) {
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const propDesc = Object.getOwnPropertyDescriptor(proto, m);
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assert_true(propDesc.enumerable, 'method should be enumerable');
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assert_true(propDesc.configurable, 'method should be configurable');
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assert_true(propDesc.writable, 'method should be writable');
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assert_equals(typeof it[m], 'function', 'method should be a function');
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assert_equals(it[m].name, m, 'method should have the correct name');
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}
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assert_equals(it.next.length, 0, 'next should have no parameters');
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assert_equals(it.return.length, 1, 'return should have 1 parameter');
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assert_equals(typeof it.throw, 'undefined', 'throw should not exist');
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}, 'Async iterator instances should have the correct list of properties');
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promise_test(async () => {
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const s = new ReadableStream({
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start(c) {
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c.enqueue(1);
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c.enqueue(2);
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c.enqueue(3);
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c.close();
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}
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});
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const chunks = [];
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for await (const chunk of s) {
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chunks.push(chunk);
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}
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assert_array_equals(chunks, [1, 2, 3]);
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}, 'Async-iterating a push source');
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promise_test(async () => {
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let i = 1;
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const s = new ReadableStream({
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pull(c) {
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c.enqueue(i);
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if (i >= 3) {
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c.close();
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}
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i += 1;
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}
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});
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const chunks = [];
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for await (const chunk of s) {
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chunks.push(chunk);
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}
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assert_array_equals(chunks, [1, 2, 3]);
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}, 'Async-iterating a pull source');
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promise_test(async () => {
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const s = new ReadableStream({
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start(c) {
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c.enqueue(undefined);
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c.enqueue(undefined);
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c.enqueue(undefined);
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c.close();
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}
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});
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const chunks = [];
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for await (const chunk of s) {
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chunks.push(chunk);
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}
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assert_array_equals(chunks, [undefined, undefined, undefined]);
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}, 'Async-iterating a push source with undefined values');
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promise_test(async () => {
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let i = 1;
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const s = new ReadableStream({
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pull(c) {
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c.enqueue(undefined);
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if (i >= 3) {
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c.close();
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}
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i += 1;
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}
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});
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const chunks = [];
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for await (const chunk of s) {
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chunks.push(chunk);
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}
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assert_array_equals(chunks, [undefined, undefined, undefined]);
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}, 'Async-iterating a pull source with undefined values');
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promise_test(async () => {
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let i = 1;
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const s = recordingReadableStream({
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pull(c) {
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c.enqueue(i);
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if (i >= 3) {
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c.close();
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}
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i += 1;
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},
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}, new CountQueuingStrategy({ highWaterMark: 0 }));
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const it = s.values();
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assert_array_equals(s.events, []);
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const read1 = await it.next();
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assert_iter_result(read1, 1, false);
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assert_array_equals(s.events, ['pull']);
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const read2 = await it.next();
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assert_iter_result(read2, 2, false);
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assert_array_equals(s.events, ['pull', 'pull']);
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const read3 = await it.next();
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assert_iter_result(read3, 3, false);
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assert_array_equals(s.events, ['pull', 'pull', 'pull']);
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const read4 = await it.next();
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assert_iter_result(read4, undefined, true);
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assert_array_equals(s.events, ['pull', 'pull', 'pull']);
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}, 'Async-iterating a pull source manually');
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promise_test(async () => {
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const s = new ReadableStream({
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start(c) {
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c.error('e');
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},
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});
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try {
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for await (const chunk of s) {}
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assert_unreached();
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} catch (e) {
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assert_equals(e, 'e');
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}
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}, 'Async-iterating an errored stream throws');
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promise_test(async () => {
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const s = new ReadableStream({
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start(c) {
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c.close();
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}
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});
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for await (const chunk of s) {
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assert_unreached();
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}
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}, 'Async-iterating a closed stream never executes the loop body, but works fine');
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promise_test(async () => {
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const s = new ReadableStream();
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const loop = async () => {
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for await (const chunk of s) {
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assert_unreached();
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}
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assert_unreached();
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};
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await Promise.race([
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loop(),
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flushAsyncEvents()
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]);
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}, 'Async-iterating an empty but not closed/errored stream never executes the loop body and stalls the async function');
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promise_test(async () => {
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const s = new ReadableStream({
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start(c) {
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c.enqueue(1);
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c.enqueue(2);
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c.enqueue(3);
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c.close();
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},
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});
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const reader = s.getReader();
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const readResult = await reader.read();
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assert_iter_result(readResult, 1, false);
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reader.releaseLock();
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const chunks = [];
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for await (const chunk of s) {
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chunks.push(chunk);
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}
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assert_array_equals(chunks, [2, 3]);
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}, 'Async-iterating a partially consumed stream');
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for (const type of ['throw', 'break', 'return']) {
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for (const preventCancel of [false, true]) {
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promise_test(async () => {
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const s = recordingReadableStream({
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start(c) {
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c.enqueue(0);
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}
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});
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// use a separate function for the loop body so return does not stop the test
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const loop = async () => {
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for await (const c of s.values({ preventCancel })) {
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if (type === 'throw') {
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throw new Error();
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} else if (type === 'break') {
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break;
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} else if (type === 'return') {
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return;
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}
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}
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};
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try {
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await loop();
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} catch (e) {}
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if (preventCancel) {
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assert_array_equals(s.events, ['pull'], `cancel() should not be called`);
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} else {
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assert_array_equals(s.events, ['pull', 'cancel', undefined], `cancel() should be called`);
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}
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}, `Cancellation behavior when ${type}ing inside loop body; preventCancel = ${preventCancel}`);
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}
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}
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for (const preventCancel of [false, true]) {
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promise_test(async () => {
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const s = recordingReadableStream({
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start(c) {
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c.enqueue(0);
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}
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});
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const it = s.values({ preventCancel });
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await it.return();
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if (preventCancel) {
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assert_array_equals(s.events, [], `cancel() should not be called`);
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} else {
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assert_array_equals(s.events, ['cancel', undefined], `cancel() should be called`);
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}
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}, `Cancellation behavior when manually calling return(); preventCancel = ${preventCancel}`);
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}
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promise_test(async t => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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if (timesPulled === 0) {
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c.enqueue(0);
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++timesPulled;
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} else {
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c.error(error1);
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}
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResult1 = await it.next();
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assert_iter_result(iterResult1, 0, false, '1st next()');
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await promise_rejects_exactly(t, error1, it.next(), '2nd next()');
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}, 'next() rejects if the stream errors');
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promise_test(async () => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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if (timesPulled === 0) {
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c.enqueue(0);
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++timesPulled;
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} else {
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c.error(error1);
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}
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResult = await it.return('return value');
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assert_iter_result(iterResult, 'return value', true);
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}, 'return() does not rejects if the stream has not errored yet');
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promise_test(async t => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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// Do not error in start() because doing so would prevent acquiring a reader/async iterator.
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c.error(error1);
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}
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});
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const it = s[Symbol.asyncIterator]();
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await flushAsyncEvents();
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await promise_rejects_exactly(t, error1, it.return('return value'));
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}, 'return() rejects if the stream has errored');
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promise_test(async t => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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if (timesPulled === 0) {
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c.enqueue(0);
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++timesPulled;
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} else {
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c.error(error1);
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}
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResult1 = await it.next();
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assert_iter_result(iterResult1, 0, false, '1st next()');
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await promise_rejects_exactly(t, error1, it.next(), '2nd next()');
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const iterResult3 = await it.next();
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assert_iter_result(iterResult3, undefined, true, '3rd next()');
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}, 'next() that succeeds; next() that reports an error; next()');
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promise_test(async () => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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if (timesPulled === 0) {
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c.enqueue(0);
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++timesPulled;
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} else {
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c.error(error1);
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}
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResults = await Promise.allSettled([it.next(), it.next(), it.next()]);
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assert_equals(iterResults[0].status, 'fulfilled', '1st next() promise status');
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assert_iter_result(iterResults[0].value, 0, false, '1st next()');
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assert_equals(iterResults[1].status, 'rejected', '2nd next() promise status');
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assert_equals(iterResults[1].reason, error1, '2nd next() rejection reason');
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assert_equals(iterResults[2].status, 'fulfilled', '3rd next() promise status');
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assert_iter_result(iterResults[2].value, undefined, true, '3rd next()');
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}, 'next() that succeeds; next() that reports an error(); next() [no awaiting]');
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promise_test(async t => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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if (timesPulled === 0) {
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c.enqueue(0);
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++timesPulled;
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} else {
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c.error(error1);
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}
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResult1 = await it.next();
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assert_iter_result(iterResult1, 0, false, '1st next()');
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await promise_rejects_exactly(t, error1, it.next(), '2nd next()');
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const iterResult3 = await it.return('return value');
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assert_iter_result(iterResult3, 'return value', true, 'return()');
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}, 'next() that succeeds; next() that reports an error(); return()');
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promise_test(async () => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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if (timesPulled === 0) {
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c.enqueue(0);
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++timesPulled;
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} else {
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c.error(error1);
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}
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResults = await Promise.allSettled([it.next(), it.next(), it.return('return value')]);
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assert_equals(iterResults[0].status, 'fulfilled', '1st next() promise status');
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assert_iter_result(iterResults[0].value, 0, false, '1st next()');
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assert_equals(iterResults[1].status, 'rejected', '2nd next() promise status');
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assert_equals(iterResults[1].reason, error1, '2nd next() rejection reason');
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assert_equals(iterResults[2].status, 'fulfilled', 'return() promise status');
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assert_iter_result(iterResults[2].value, 'return value', true, 'return()');
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}, 'next() that succeeds; next() that reports an error(); return() [no awaiting]');
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promise_test(async () => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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c.enqueue(timesPulled);
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++timesPulled;
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResult1 = await it.next();
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assert_iter_result(iterResult1, 0, false, 'next()');
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const iterResult2 = await it.return('return value');
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assert_iter_result(iterResult2, 'return value', true, 'return()');
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assert_equals(timesPulled, 2);
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}, 'next() that succeeds; return()');
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promise_test(async () => {
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let timesPulled = 0;
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const s = new ReadableStream({
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pull(c) {
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c.enqueue(timesPulled);
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++timesPulled;
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}
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});
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const it = s[Symbol.asyncIterator]();
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const iterResults = await Promise.allSettled([it.next(), it.return('return value')]);
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assert_equals(iterResults[0].status, 'fulfilled', 'next() promise status');
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assert_iter_result(iterResults[0].value, 0, false, 'next()');
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assert_equals(iterResults[1].status, 'fulfilled', 'return() promise status');
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assert_iter_result(iterResults[1].value, 'return value', true, 'return()');
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assert_equals(timesPulled, 2);
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}, 'next() that succeeds; return() [no awaiting]');
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promise_test(async () => {
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const rs = new ReadableStream();
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const it = rs.values();
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const iterResult1 = await it.return('return value');
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assert_iter_result(iterResult1, 'return value', true, 'return()');
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const iterResult2 = await it.next();
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assert_iter_result(iterResult2, undefined, true, 'next()');
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}, 'return(); next()');
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promise_test(async () => {
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const rs = new ReadableStream();
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const it = rs.values();
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const resolveOrder = [];
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const iterResults = await Promise.allSettled([
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it.return('return value').then(result => {
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resolveOrder.push('return');
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return result;
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}),
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it.next().then(result => {
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resolveOrder.push('next');
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return result;
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})
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]);
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assert_equals(iterResults[0].status, 'fulfilled', 'return() promise status');
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assert_iter_result(iterResults[0].value, 'return value', true, 'return()');
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assert_equals(iterResults[1].status, 'fulfilled', 'next() promise status');
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assert_iter_result(iterResults[1].value, undefined, true, 'next()');
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assert_array_equals(resolveOrder, ['return', 'next'], 'next() resolves after return()');
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}, 'return(); next() [no awaiting]');
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promise_test(async () => {
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let resolveCancelPromise;
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const rs = recordingReadableStream({
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cancel(reason) {
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return new Promise(r => resolveCancelPromise = r);
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}
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});
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const it = rs.values();
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let returnResolved = false;
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const returnPromise = it.return('return value').then(result => {
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returnResolved = true;
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return result;
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});
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await flushAsyncEvents();
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assert_false(returnResolved, 'return() should not resolve while cancel() promise is pending');
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resolveCancelPromise();
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const iterResult1 = await returnPromise;
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assert_iter_result(iterResult1, 'return value', true, 'return()');
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const iterResult2 = await it.next();
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assert_iter_result(iterResult2, undefined, true, 'next()');
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}, 'return(); next() with delayed cancel()');
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promise_test(async () => {
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let resolveCancelPromise;
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const rs = recordingReadableStream({
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cancel(reason) {
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return new Promise(r => resolveCancelPromise = r);
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}
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});
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const it = rs.values();
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const resolveOrder = [];
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const returnPromise = it.return('return value').then(result => {
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resolveOrder.push('return');
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return result;
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});
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const nextPromise = it.next().then(result => {
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resolveOrder.push('next');
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return result;
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|
});
|
|
|
|
assert_array_equals(rs.events, ['cancel', 'return value'], 'return() should call cancel()');
|
|
assert_array_equals(resolveOrder, [], 'return() should not resolve before cancel() resolves');
|
|
|
|
resolveCancelPromise();
|
|
const iterResult1 = await returnPromise;
|
|
assert_iter_result(iterResult1, 'return value', true, 'return() should resolve with original reason');
|
|
const iterResult2 = await nextPromise;
|
|
assert_iter_result(iterResult2, undefined, true, 'next() should resolve with done result');
|
|
|
|
assert_array_equals(rs.events, ['cancel', 'return value'], 'no pull() after cancel()');
|
|
assert_array_equals(resolveOrder, ['return', 'next'], 'next() should resolve after return() resolves');
|
|
|
|
}, 'return(); next() with delayed cancel() [no awaiting]');
|
|
|
|
promise_test(async () => {
|
|
const rs = new ReadableStream();
|
|
const it = rs.values();
|
|
|
|
const iterResult1 = await it.return('return value 1');
|
|
assert_iter_result(iterResult1, 'return value 1', true, '1st return()');
|
|
|
|
const iterResult2 = await it.return('return value 2');
|
|
assert_iter_result(iterResult2, 'return value 2', true, '1st return()');
|
|
}, 'return(); return()');
|
|
|
|
promise_test(async () => {
|
|
const rs = new ReadableStream();
|
|
const it = rs.values();
|
|
|
|
const resolveOrder = [];
|
|
const iterResults = await Promise.allSettled([
|
|
it.return('return value 1').then(result => {
|
|
resolveOrder.push('return 1');
|
|
return result;
|
|
}),
|
|
it.return('return value 2').then(result => {
|
|
resolveOrder.push('return 2');
|
|
return result;
|
|
})
|
|
]);
|
|
|
|
assert_equals(iterResults[0].status, 'fulfilled', '1st return() promise status');
|
|
assert_iter_result(iterResults[0].value, 'return value 1', true, '1st return()');
|
|
|
|
assert_equals(iterResults[1].status, 'fulfilled', '2nd return() promise status');
|
|
assert_iter_result(iterResults[1].value, 'return value 2', true, '1st return()');
|
|
|
|
assert_array_equals(resolveOrder, ['return 1', 'return 2'], '2nd return() resolves after 1st return()');
|
|
}, 'return(); return() [no awaiting]');
|
|
|
|
test(() => {
|
|
const s = new ReadableStream({
|
|
start(c) {
|
|
c.enqueue(0);
|
|
c.close();
|
|
},
|
|
});
|
|
s.values();
|
|
assert_throws_js(TypeError, () => s.values(), 'values() should throw');
|
|
}, 'values() throws if there\'s already a lock');
|
|
|
|
promise_test(async () => {
|
|
const s = new ReadableStream({
|
|
start(c) {
|
|
c.enqueue(1);
|
|
c.enqueue(2);
|
|
c.enqueue(3);
|
|
c.close();
|
|
}
|
|
});
|
|
|
|
const chunks = [];
|
|
for await (const chunk of s) {
|
|
chunks.push(chunk);
|
|
}
|
|
assert_array_equals(chunks, [1, 2, 3]);
|
|
|
|
const reader = s.getReader();
|
|
await reader.closed;
|
|
}, 'Acquiring a reader after exhaustively async-iterating a stream');
|
|
|
|
promise_test(async t => {
|
|
let timesPulled = 0;
|
|
const s = new ReadableStream({
|
|
pull(c) {
|
|
if (timesPulled === 0) {
|
|
c.enqueue(0);
|
|
++timesPulled;
|
|
} else {
|
|
c.error(error1);
|
|
}
|
|
}
|
|
});
|
|
|
|
const it = s[Symbol.asyncIterator]({ preventCancel: true });
|
|
|
|
const iterResult1 = await it.next();
|
|
assert_iter_result(iterResult1, 0, false, '1st next()');
|
|
|
|
await promise_rejects_exactly(t, error1, it.next(), '2nd next()');
|
|
|
|
const iterResult2 = await it.return('return value');
|
|
assert_iter_result(iterResult2, 'return value', true, 'return()');
|
|
|
|
// i.e. it should not reject with a generic "this stream is locked" TypeError.
|
|
const reader = s.getReader();
|
|
await promise_rejects_exactly(t, error1, reader.closed, 'closed on the new reader should reject with the error');
|
|
}, 'Acquiring a reader after return()ing from a stream that errors');
|
|
|
|
promise_test(async () => {
|
|
const s = new ReadableStream({
|
|
start(c) {
|
|
c.enqueue(1);
|
|
c.enqueue(2);
|
|
c.enqueue(3);
|
|
c.close();
|
|
},
|
|
});
|
|
|
|
// read the first two chunks, then cancel
|
|
const chunks = [];
|
|
for await (const chunk of s) {
|
|
chunks.push(chunk);
|
|
if (chunk >= 2) {
|
|
break;
|
|
}
|
|
}
|
|
assert_array_equals(chunks, [1, 2]);
|
|
|
|
const reader = s.getReader();
|
|
await reader.closed;
|
|
}, 'Acquiring a reader after partially async-iterating a stream');
|
|
|
|
promise_test(async () => {
|
|
const s = new ReadableStream({
|
|
start(c) {
|
|
c.enqueue(1);
|
|
c.enqueue(2);
|
|
c.enqueue(3);
|
|
c.close();
|
|
},
|
|
});
|
|
|
|
// read the first two chunks, then release lock
|
|
const chunks = [];
|
|
for await (const chunk of s.values({preventCancel: true})) {
|
|
chunks.push(chunk);
|
|
if (chunk >= 2) {
|
|
break;
|
|
}
|
|
}
|
|
assert_array_equals(chunks, [1, 2]);
|
|
|
|
const reader = s.getReader();
|
|
const readResult = await reader.read();
|
|
assert_iter_result(readResult, 3, false);
|
|
await reader.closed;
|
|
}, 'Acquiring a reader and reading the remaining chunks after partially async-iterating a stream with preventCancel = true');
|
|
|
|
for (const preventCancel of [false, true]) {
|
|
test(() => {
|
|
const rs = new ReadableStream();
|
|
rs.values({ preventCancel }).return();
|
|
// The test passes if this line doesn't throw.
|
|
rs.getReader();
|
|
}, `return() should unlock the stream synchronously when preventCancel = ${preventCancel}`);
|
|
}
|
|
|
|
promise_test(async () => {
|
|
const rs = new ReadableStream({
|
|
async start(c) {
|
|
c.enqueue('a');
|
|
c.enqueue('b');
|
|
c.enqueue('c');
|
|
await flushAsyncEvents();
|
|
// At this point, the async iterator has a read request in the stream's queue for its pending next() promise.
|
|
// Closing the stream now causes two things to happen *synchronously*:
|
|
// 1. ReadableStreamClose resolves reader.[[closedPromise]] with undefined.
|
|
// 2. ReadableStreamClose calls the read request's close steps, which calls ReadableStreamReaderGenericRelease,
|
|
// which replaces reader.[[closedPromise]] with a rejected promise.
|
|
c.close();
|
|
}
|
|
});
|
|
|
|
const chunks = [];
|
|
for await (const chunk of rs) {
|
|
chunks.push(chunk);
|
|
}
|
|
assert_array_equals(chunks, ['a', 'b', 'c']);
|
|
}, 'close() while next() is pending');
|