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How to use writableStartPromise method in wpt
Best JavaScript code snippet using wpt
flow-control.js
Source:flow-control.js 
1'use strict';2if (self.importScripts) {3 self.importScripts('/resources/testharness.js');4 self.importScripts('../resources/test-utils.js');5 self.importScripts('../resources/rs-utils.js');6 self.importScripts('../resources/recording-streams.js');7}8const error1 = new Error('error1!');9error1.name = 'error1';10promise_test(t => {11 const rs = recordingReadableStream({12 start(controller) {13 controller.enqueue('a');14 controller.enqueue('b');15 controller.close();16 }17 });18 const ws = recordingWritableStream(undefined, new CountQueuingStrategy({ highWaterMark: 0 }));19 const pipePromise = rs.pipeTo(ws, { preventCancel: true });20 // Wait and make sure it doesn't do any reading.21 return flushAsyncEvents().then(() => {22 ws.controller.error(error1);23 })24 .then(() => promise_rejects(t, error1, pipePromise, 'pipeTo must reject with the same error'))25 .then(() => {26 assert_array_equals(rs.eventsWithoutPulls, []);27 assert_array_equals(ws.events, []);28 })29 .then(() => readableStreamToArray(rs))30 .then(chunksNotPreviouslyRead => {31 assert_array_equals(chunksNotPreviouslyRead, ['a', 'b']);32 });33}, 'Piping from a non-empty ReadableStream into a WritableStream that does not desire chunks');34promise_test(() => {35 const rs = recordingReadableStream({36 start(controller) {37 controller.enqueue('b');38 controller.close();39 }40 });41 let resolveWritePromise;42 const ws = recordingWritableStream({43 write() {44 if (!resolveWritePromise) {45 // first write46 return new Promise(resolve => {47 resolveWritePromise = resolve;48 });49 }50 return undefined;51 }52 });53 const writer = ws.getWriter();54 const firstWritePromise = writer.write('a');55 assert_equals(writer.desiredSize, 0, 'after writing the writer\'s desiredSize must be 0');56 writer.releaseLock();57 // firstWritePromise won't settle until we call resolveWritePromise.58 const pipePromise = rs.pipeTo(ws);59 return flushAsyncEvents().then(() => resolveWritePromise())60 .then(() => Promise.all([firstWritePromise, pipePromise]))61 .then(() => {62 assert_array_equals(rs.eventsWithoutPulls, []);63 assert_array_equals(ws.events, ['write', 'a', 'write', 'b', 'close']);64 });65}, 'Piping from a non-empty ReadableStream into a WritableStream that does not desire chunks, but then does');66promise_test(() => {67 const rs = recordingReadableStream();68 const startPromise = Promise.resolve();69 let resolveWritePromise;70 const ws = recordingWritableStream({71 start() {72 return startPromise;73 },74 write() {75 if (!resolveWritePromise) {76 // first write77 return new Promise(resolve => {78 resolveWritePromise = resolve;79 });80 }81 return undefined;82 }83 });84 const writer = ws.getWriter();85 writer.write('a');86 return startPromise.then(() => {87 assert_array_equals(ws.events, ['write', 'a']);88 assert_equals(writer.desiredSize, 0, 'after writing the writer\'s desiredSize must be 0');89 writer.releaseLock();90 const pipePromise = rs.pipeTo(ws);91 rs.controller.enqueue('b');92 resolveWritePromise();93 rs.controller.close();94 return pipePromise.then(() => {95 assert_array_equals(rs.eventsWithoutPulls, []);96 assert_array_equals(ws.events, ['write', 'a', 'write', 'b', 'close']);97 });98 });99}, 'Piping from an empty ReadableStream into a WritableStream that does not desire chunks, but then the readable ' +100 'stream becomes non-empty and the writable stream starts desiring chunks');101promise_test(() => {102 const unreadChunks = ['b', 'c', 'd'];103 const rs = recordingReadableStream({104 pull(controller) {105 controller.enqueue(unreadChunks.shift());106 if (unreadChunks.length === 0) {107 controller.close();108 }109 }110 }, new CountQueuingStrategy({ highWaterMark: 0 }));111 let resolveWritePromise;112 const ws = recordingWritableStream({113 write() {114 if (!resolveWritePromise) {115 // first write116 return new Promise(resolve => {117 resolveWritePromise = resolve;118 });119 }120 return undefined;121 }122 }, new CountQueuingStrategy({ highWaterMark: 3 }));123 const writer = ws.getWriter();124 const firstWritePromise = writer.write('a');125 assert_equals(writer.desiredSize, 2, 'after writing the writer\'s desiredSize must be 2');126 writer.releaseLock();127 // firstWritePromise won't settle until we call resolveWritePromise.128 const pipePromise = rs.pipeTo(ws);129 return flushAsyncEvents().then(() => {130 assert_array_equals(ws.events, ['write', 'a']);131 assert_equals(unreadChunks.length, 1, 'chunks should continue to be enqueued until the HWM is reached');132 }).then(() => resolveWritePromise())133 .then(() => Promise.all([firstWritePromise, pipePromise]))134 .then(() => {135 assert_array_equals(rs.events, ['pull', 'pull', 'pull']);136 assert_array_equals(ws.events, ['write', 'a', 'write', 'b','write', 'c','write', 'd', 'close']);137 });138}, 'Piping from a ReadableStream to a WritableStream that desires more chunks before finishing with previous ones');139class StepTracker {140 constructor() {141 this.waiters = [];142 this.wakers = [];143 }144 // Returns promise which resolves when step `n` is reached. Also schedules step n + 1 to happen shortly after the145 // promise is resolved.146 waitThenAdvance(n) {147 if (this.waiters[n] === undefined) {148 this.waiters[n] = new Promise(resolve => {149 this.wakers[n] = resolve;150 });151 this.waiters[n]152 .then(() => flushAsyncEvents())153 .then(() => {154 if (this.wakers[n + 1] !== undefined) {155 this.wakers[n + 1]();156 }157 });158 }159 if (n == 0) {160 this.wakers[0]();161 }162 return this.waiters[n];163 }164}165promise_test(() => {166 const steps = new StepTracker();167 const desiredSizes = [];168 const rs = recordingReadableStream({169 start(controller) {170 steps.waitThenAdvance(1).then(() => enqueue('a'));171 steps.waitThenAdvance(3).then(() => enqueue('b'));172 steps.waitThenAdvance(5).then(() => enqueue('c'));173 steps.waitThenAdvance(7).then(() => enqueue('d'));174 steps.waitThenAdvance(11).then(() => controller.close());175 function enqueue(chunk) {176 controller.enqueue(chunk);177 desiredSizes.push(controller.desiredSize);178 }179 }180 });181 const chunksFinishedWriting = [];182 const writableStartPromise = Promise.resolve();183 let writeCalled = false;184 const ws = recordingWritableStream({185 start() {186 return writableStartPromise;187 },188 write(chunk) {189 const waitForStep = writeCalled ? 12 : 9;190 writeCalled = true;191 return steps.waitThenAdvance(waitForStep).then(() => {192 chunksFinishedWriting.push(chunk);193 });194 }195 });196 return writableStartPromise.then(() => {197 const pipePromise = rs.pipeTo(ws);198 steps.waitThenAdvance(0);199 return Promise.all([200 steps.waitThenAdvance(2).then(() => {201 assert_array_equals(chunksFinishedWriting, [], 'at step 2, zero chunks must have finished writing');202 assert_array_equals(ws.events, ['write', 'a'], 'at step 2, one chunk must have been written');203 // When 'a' (the very first chunk) was enqueued, it was immediately used to fulfill the outstanding read request204 // promise, leaving the queue empty.205 assert_array_equals(desiredSizes, [1],206 'at step 2, the desiredSize at the last enqueue (step 1) must have been 1');207 assert_equals(rs.controller.desiredSize, 1, 'at step 2, the current desiredSize must be 1');208 }),209 steps.waitThenAdvance(4).then(() => {210 assert_array_equals(chunksFinishedWriting, [], 'at step 4, zero chunks must have finished writing');211 assert_array_equals(ws.events, ['write', 'a'], 'at step 4, one chunk must have been written');212 // When 'b' was enqueued at step 3, the queue was also empty, since immediately after enqueuing 'a' at213 // step 1, it was dequeued in order to fulfill the read() call that was made at step 0. Thus the queue214 // had size 1 (thus desiredSize of 0).215 assert_array_equals(desiredSizes, [1, 0],216 'at step 4, the desiredSize at the last enqueue (step 3) must have been 0');217 assert_equals(rs.controller.desiredSize, 0, 'at step 4, the current desiredSize must be 0');218 }),219 steps.waitThenAdvance(6).then(() => {220 assert_array_equals(chunksFinishedWriting, [], 'at step 6, zero chunks must have finished writing');221 assert_array_equals(ws.events, ['write', 'a'], 'at step 6, one chunk must have been written');222 // When 'c' was enqueued at step 5, the queue was not empty; it had 'b' in it, since 'b' will not be read until223 // the first write completes at step 9. Thus, the queue size is 2 after enqueuing 'c', giving a desiredSize of224 // -1.225 assert_array_equals(desiredSizes, [1, 0, -1],226 'at step 6, the desiredSize at the last enqueue (step 5) must have been -1');227 assert_equals(rs.controller.desiredSize, -1, 'at step 6, the current desiredSize must be -1');228 }),229 steps.waitThenAdvance(8).then(() => {230 assert_array_equals(chunksFinishedWriting, [], 'at step 8, zero chunks must have finished writing');231 assert_array_equals(ws.events, ['write', 'a'], 'at step 8, one chunk must have been written');232 // When 'd' was enqueued at step 7, the situation is the same as before, leading to a queue containing 'b', 'c',233 // and 'd'.234 assert_array_equals(desiredSizes, [1, 0, -1, -2],235 'at step 8, the desiredSize at the last enqueue (step 7) must have been -2');236 assert_equals(rs.controller.desiredSize, -2, 'at step 8, the current desiredSize must be -2');237 }),238 steps.waitThenAdvance(10).then(() => {239 assert_array_equals(chunksFinishedWriting, ['a'], 'at step 10, one chunk must have finished writing');240 assert_array_equals(ws.events, ['write', 'a', 'write', 'b'],241 'at step 10, two chunks must have been written');242 assert_equals(rs.controller.desiredSize, -1, 'at step 10, the current desiredSize must be -1');243 }),244 pipePromise.then(() => {245 assert_array_equals(desiredSizes, [1, 0, -1, -2], 'backpressure must have been exerted at the source');246 assert_array_equals(chunksFinishedWriting, ['a', 'b', 'c', 'd'], 'all chunks finished writing');247 assert_array_equals(rs.eventsWithoutPulls, [], 'nothing unexpected should happen to the ReadableStream');248 assert_array_equals(ws.events, ['write', 'a', 'write', 'b', 'write', 'c', 'write', 'd', 'close'],249 'all chunks were written (and the WritableStream closed)');250 })251 ]);252 });253}, 'Piping to a WritableStream that does not consume the writes fast enough exerts backpressure on the ReadableStream');...
aflprep_flow-control.any.js
Source:aflprep_flow-control.any.js
1'use strict';2const error1 = new Error('error1!');3error1.name = 'error1';4promise_test(t => {5 const rs = recordingReadableStream({6 start(controller) {7 controller.enqueue('a');8 controller.enqueue('b');9 controller.close();10 }11 });12 const ws = recordingWritableStream(undefined, new CountQueuingStrategy({ highWaterMark: 0 }));13 const pipePromise = rs.pipeTo(ws, { preventCancel: true });14 return flushAsyncEvents().then(() => {15 ws.controller.error(error1);16 })17 .then(() => promise_rejects_exactly(t, error1, pipePromise, 'pipeTo must reject with the same error'))18 .then(() => {19 assert_array_equals(rs.eventsWithoutPulls, []);20 assert_array_equals(ws.events, []);21 })22 .then(() => readableStreamToArray(rs))23 .then(chunksNotPreviouslyRead => {24 assert_array_equals(chunksNotPreviouslyRead, ['a', 'b']);25 });26}, 'Piping from a non-empty ReadableStream into a WritableStream that does not desire chunks');27promise_test(() => {28 const rs = recordingReadableStream({29 start(controller) {30 controller.enqueue('b');31 controller.close();32 }33 });34 let resolveWritePromise;35 const ws = recordingWritableStream({36 write() {37 if (!resolveWritePromise) {38 return new Promise(resolve => {39 resolveWritePromise = resolve;40 });41 }42 return undefined;43 }44 });45 const writer = ws.getWriter();46 const firstWritePromise = writer.write('a');47 assert_equals(writer.desiredSize, 0, 'after writing the writer\'s desiredSize must be 0');48 writer.releaseLock();49 const pipePromise = rs.pipeTo(ws);50 return flushAsyncEvents().then(() => resolveWritePromise())51 .then(() => Promise.all([firstWritePromise, pipePromise]))52 .then(() => {53 assert_array_equals(rs.eventsWithoutPulls, []);54 assert_array_equals(ws.events, ['write', 'a', 'write', 'b', 'close']);55 });56}, 'Piping from a non-empty ReadableStream into a WritableStream that does not desire chunks, but then does');57promise_test(() => {58 const rs = recordingReadableStream();59 let resolveWritePromise;60 const ws = recordingWritableStream({61 write() {62 if (!resolveWritePromise) {63 return new Promise(resolve => {64 resolveWritePromise = resolve;65 });66 }67 return undefined;68 }69 });70 const writer = ws.getWriter();71 writer.write('a');72 return flushAsyncEvents().then(() => {73 assert_array_equals(ws.events, ['write', 'a']);74 assert_equals(writer.desiredSize, 0, 'after writing the writer\'s desiredSize must be 0');75 writer.releaseLock();76 const pipePromise = rs.pipeTo(ws);77 rs.controller.enqueue('b');78 resolveWritePromise();79 rs.controller.close();80 return pipePromise.then(() => {81 assert_array_equals(rs.eventsWithoutPulls, []);82 assert_array_equals(ws.events, ['write', 'a', 'write', 'b', 'close']);83 });84 });85}, 'Piping from an empty ReadableStream into a WritableStream that does not desire chunks, but then the readable ' +86 'stream becomes non-empty and the writable stream starts desiring chunks');87promise_test(() => {88 const unreadChunks = ['b', 'c', 'd'];89 const rs = recordingReadableStream({90 pull(controller) {91 controller.enqueue(unreadChunks.shift());92 if (unreadChunks.length === 0) {93 controller.close();94 }95 }96 }, new CountQueuingStrategy({ highWaterMark: 0 }));97 let resolveWritePromise;98 const ws = recordingWritableStream({99 write() {100 if (!resolveWritePromise) {101 return new Promise(resolve => {102 resolveWritePromise = resolve;103 });104 }105 return undefined;106 }107 }, new CountQueuingStrategy({ highWaterMark: 3 }));108 const writer = ws.getWriter();109 const firstWritePromise = writer.write('a');110 assert_equals(writer.desiredSize, 2, 'after writing the writer\'s desiredSize must be 2');111 writer.releaseLock();112 const pipePromise = rs.pipeTo(ws);113 return flushAsyncEvents().then(() => {114 assert_array_equals(ws.events, ['write', 'a']);115 assert_equals(unreadChunks.length, 1, 'chunks should continue to be enqueued until the HWM is reached');116 }).then(() => resolveWritePromise())117 .then(() => Promise.all([firstWritePromise, pipePromise]))118 .then(() => {119 assert_array_equals(rs.events, ['pull', 'pull', 'pull']);120 assert_array_equals(ws.events, ['write', 'a', 'write', 'b','write', 'c','write', 'd', 'close']);121 });122}, 'Piping from a ReadableStream to a WritableStream that desires more chunks before finishing with previous ones');123class StepTracker {124 constructor() {125 this.waiters = [];126 this.wakers = [];127 }128 waitThenAdvance(n) {129 if (this.waiters[n] === undefined) {130 this.waiters[n] = new Promise(resolve => {131 this.wakers[n] = resolve;132 });133 this.waiters[n]134 .then(() => flushAsyncEvents())135 .then(() => {136 if (this.wakers[n + 1] !== undefined) {137 this.wakers[n + 1]();138 }139 });140 }141 if (n == 0) {142 this.wakers[0]();143 }144 return this.waiters[n];145 }146}147promise_test(() => {148 const steps = new StepTracker();149 const desiredSizes = [];150 const rs = recordingReadableStream({151 start(controller) {152 steps.waitThenAdvance(1).then(() => enqueue('a'));153 steps.waitThenAdvance(3).then(() => enqueue('b'));154 steps.waitThenAdvance(5).then(() => enqueue('c'));155 steps.waitThenAdvance(7).then(() => enqueue('d'));156 steps.waitThenAdvance(11).then(() => controller.close());157 function enqueue(chunk) {158 controller.enqueue(chunk);159 desiredSizes.push(controller.desiredSize);160 }161 }162 });163 const chunksFinishedWriting = [];164 const writableStartPromise = Promise.resolve();165 let writeCalled = false;166 const ws = recordingWritableStream({167 start() {168 return writableStartPromise;169 },170 write(chunk) {171 const waitForStep = writeCalled ? 12 : 9;172 writeCalled = true;173 return steps.waitThenAdvance(waitForStep).then(() => {174 chunksFinishedWriting.push(chunk);175 });176 }177 });178 return writableStartPromise.then(() => {179 const pipePromise = rs.pipeTo(ws);180 steps.waitThenAdvance(0);181 return Promise.all([182 steps.waitThenAdvance(2).then(() => {183 assert_array_equals(chunksFinishedWriting, [], 'at step 2, zero chunks must have finished writing');184 assert_array_equals(ws.events, ['write', 'a'], 'at step 2, one chunk must have been written');185 assert_array_equals(desiredSizes, [1],186 'at step 2, the desiredSize at the last enqueue (step 1) must have been 1');187 assert_equals(rs.controller.desiredSize, 1, 'at step 2, the current desiredSize must be 1');188 }),189 steps.waitThenAdvance(4).then(() => {190 assert_array_equals(chunksFinishedWriting, [], 'at step 4, zero chunks must have finished writing');191 assert_array_equals(ws.events, ['write', 'a'], 'at step 4, one chunk must have been written');192 assert_array_equals(desiredSizes, [1, 0],193 'at step 4, the desiredSize at the last enqueue (step 3) must have been 0');194 assert_equals(rs.controller.desiredSize, 0, 'at step 4, the current desiredSize must be 0');195 }),196 steps.waitThenAdvance(6).then(() => {197 assert_array_equals(chunksFinishedWriting, [], 'at step 6, zero chunks must have finished writing');198 assert_array_equals(ws.events, ['write', 'a'], 'at step 6, one chunk must have been written');199 assert_array_equals(desiredSizes, [1, 0, -1],200 'at step 6, the desiredSize at the last enqueue (step 5) must have been -1');201 assert_equals(rs.controller.desiredSize, -1, 'at step 6, the current desiredSize must be -1');202 }),203 steps.waitThenAdvance(8).then(() => {204 assert_array_equals(chunksFinishedWriting, [], 'at step 8, zero chunks must have finished writing');205 assert_array_equals(ws.events, ['write', 'a'], 'at step 8, one chunk must have been written');206 assert_array_equals(desiredSizes, [1, 0, -1, -2],207 'at step 8, the desiredSize at the last enqueue (step 7) must have been -2');208 assert_equals(rs.controller.desiredSize, -2, 'at step 8, the current desiredSize must be -2');209 }),210 steps.waitThenAdvance(10).then(() => {211 assert_array_equals(chunksFinishedWriting, ['a'], 'at step 10, one chunk must have finished writing');212 assert_array_equals(ws.events, ['write', 'a', 'write', 'b'],213 'at step 10, two chunks must have been written');214 assert_equals(rs.controller.desiredSize, -1, 'at step 10, the current desiredSize must be -1');215 }),216 pipePromise.then(() => {217 assert_array_equals(desiredSizes, [1, 0, -1, -2], 'backpressure must have been exerted at the source');218 assert_array_equals(chunksFinishedWriting, ['a', 'b', 'c', 'd'], 'all chunks finished writing');219 assert_array_equals(rs.eventsWithoutPulls, [], 'nothing unexpected should happen to the ReadableStream');220 assert_array_equals(ws.events, ['write', 'a', 'write', 'b', 'write', 'c', 'write', 'd', 'close'],221 'all chunks were written (and the WritableStream closed)');222 })223 ]);224 });...
Using AI Code Generation
1const wpt = require('webpagetest');2const webPageTest = new wpt('WPT_API_KEY');3 videoParams: {4 }5}, (err, data) => {6 if (err) return console.error(err);7 const {data: {testId}} = data;8 webPageTest.getTestResults(testId, (err, data) => {9 if (err) return console.error(err);10 console.log(data);11 });12});
Using AI Code Generation
1const { ReadableStream, WritableStream, CountQueuingStrategy } = require('stream/web');2const fs = require('fs');3const file = fs.createWriteStream('./file.txt');4const writer = new WritableStream({5 start(controller) {6 return file.open();7 },8 write(chunk, controller) {9 return file.write(chunk);10 },11 close() {12 return file.end();13 },14 abort(reason) {15 return file.destroy(reason);16 }17});18const stream = new ReadableStream({19 start(controller) {20 controller.enqueue(data);21 controller.close();22 },23 pull(controller) {},24 cancel(reason) {}25});26await writer.writableStartPromise;27stream.pipeTo(writer)28 .then(() => console.log('The data was written successfully'))29 .catch(e => console.error(`There was an error writing the file: ${e}`));30const { ReadableStream, WritableStream, CountQueuingStrategy } = require('stream/web');31const fs = require('fs');32const file = fs.createWriteStream('./file.txt');33const writer = new WritableStream({34 start(controller) {35 this.fileHandle = file.open();36 return this.fileHandle;37 },38 write(chunk, controller) {39 return file.write(chunk);40 },41 close() {42 return file.end();43 },44 abort(reason) {45 return file.destroy(reason);46 }47});48const stream = new ReadableStream({49 start(controller) {50 controller.enqueue(data);51 controller.close();52 },53 pull(controller) {},54 cancel(reason) {}55});56await writer.writableStartPromise;57stream.pipeTo(writer)58 .then(() => console
Using AI Code Generation
1var wpt = require('wpt-api');2var api = new wpt('API_KEY');3var data = {4};5api.runTest(data, function (err, data) {6 if (err) {7 console.log(err);8 } else {9 api.writableStartPromise(data.data.testId, function (err, data) {10 if (err) {11 console.log(err);12 } else {13 console.log(data);14 }15 });16 }17});18The MIT License (MIT)19* [WebPageTest](
Using AI Code Generation
1const wpt = require('webpagetest')2const wpt = new WebPageTest('www.webpagetest.org', 'A.1234567890abcdef1234567890abcdef12345678');3const options = {4 lighthouseConfig: {5 "settings": {6 }7 },8 emulateUserAgentString: 'Mozilla/5.0 (Linux; Android 9; Moto G (4)) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/70.0.3538.80 Mobile Safari/537.36',
Using AI Code Generation
1function myFunction() {2 var fileHandle;3 var writable;4 var newFile = document.getElementById("newFile").value;5 const opts = {6 };7 window.chooseFileSystemEntries(opts).then(handle => {8 fileHandle = handle;9 return fileHandle.createWritable();10 }).then(writableStream => {11 writable = writableStream;12 return writable.start();13 }).then(() => {14 const blob = new Blob([newFile], { type: 'text/plain' });15 writable.write(blob);16 return writable.close();17 }).then(() => {18 console.log('All done with the write');19 }).catch(error => {20 console.error('There was an error', error);21 });22}23function myFunction() {24 var fileHandle;25 var writable;26 var newFile = document.getElementById("newFile").value;27 const opts = {28 };29 window.chooseFileSystemEntries(opts).then(handle => {30 fileHandle = handle;31 return fileHandle.createWritable();32 }).then(writableStream => {33 writable = writableStream;34 return writable.ready;35 }).then(() => {36 const blob = new Blob([newFile], { type: 'text/plain' });37 writable.write(blob);38 return writable.close();39 }).then(() => {40 console.log('All done with the write');41 }).catch(error => {42 console.error('There was an error', error);43 });44}45function myFunction() {46 var fileHandle;47 var writable;48 var newFile = document.getElementById("newFile").value;49 const opts = {50 };51 window.chooseFileSystemEntries(opts).then(handle => {52 fileHandle = handle;53 return fileHandle.createWritable();54 }).then(writableStream => {55 writable = writableStream;56 const blob = new Blob([newFile], { type: 'text/plain' });57 writable.write(blob);58 return writable.close();59 }).then(() => {60 console.log('All done with the write');61 }).catch(error => {
Using AI Code Generation
1var wpt = require('web-platform-test');2var test = wpt.test;3test(function(t) {4 var wsPromise = t.writableStartPromise(new WritableStream({5 start: function(c) {6 t.step(function() {7 assert_true(true, 'start should be called');8 });9 c.close();10 }11 }));12 return wsPromise.then(function() {13 t.done();14 });15}, 'WritableStream constructor should call start method');16test(function(t) {17 var wsPromise = t.writableStartPromise(new WritableStream({18 start: function(c) {19 t.step(function() {20 assert_true(true, 'start should be called');21 });22 c.error('error');23 }24 }));25 return wsPromise.then(function() {26 assert_unreached('start should not be called');27 }, function(e) {28 assert_equals(e, 'error', 'error should be propagated');29 }).then(t.done.bind(t), t.done.bind(t));30}, 'WritableStream constructor should propagate error from start method');31test(function(t) {32 var wsPromise = t.writableStartPromise(new WritableStream({33 start: function(c) {34 t.step(function() {35 assert_true(true, 'start should be called');36 });37 c.error('error');38 }39 }));40 return wsPromise.then(function() {41 assert_unreached('start should not be called');42 }, function(e) {43 assert_equals(e, 'error', 'error should be propagated');44 }).then(t.done.bind(t), t.done.bind(t));45}, 'WritableStream constructor should propagate error from start method');46test(function(t) {47 var wsPromise = t.writableStartPromise(new WritableStream({48 start: function() {49 throw 'error';50 }51 }));52 return wsPromise.then(function() {53 assert_unreached('start should not be called');54 }, function(e) {55 assert_equals(e, 'error', 'error should be propagated');56 }).then(t.done.bind(t), t.done.bind(t));57}, 'WritableStream constructor should propagate error from start method');58test(function(t) {59 var wsPromise = t.writableStartPromise(new WritableStream({60 start: function(c) {61 t.step(function() {62 assert_true(true, 'start should be
Using AI Code Generation
1writable.writableStartPromise.then(()=>{2 console.log("writer is ready");3 writer.write("data");4 writer.close();5});6writable.writableReady.then(()=>{7 console.log("writer is ready");8 writer.write("data");9 writer.close();10});11const reader = new ReadableStreamBYOBReader(readable);12const reader = new ReadableStreamBYOBReader(readable);13reader.read(new Uint8Array(1)).then((result)=>{14 console.log(result.value);15 result.done;16 result.request.respond(1);17});18const writer = new WritableStreamDefaultWriter(writable);19const writer = new WritableStreamDefaultWriter(writable);20writer.write("data");21writer.abort(new Error("abort"));22writable.writableAbortReason;23| cancel(reason) | Promise | Cancels the stream, signaling a loss of interest in the stream by a consumer. The supplied reason argument will be given to the underlying source's cancel() method, which might or might not use it. |24| getReader(options) | ReadableStreamDefaultReader or ReadableStreamBYOBReader | Creates a reader of the type specified by the mode option and locks the stream to the new reader. While the stream is locked, no other reader can be acquired until this one is released. |25| pipeThrough({ writable, readable }, options) | ReadableStream | Provides a convenient, chainable way of piping this readable stream through a transform stream
Using AI Code Generation
1wpt.writeableStartPromise().then(function() {2 console.log('writeable start promise resolved');3});4var wpt = {5 writeableStartPromise: function() {6 return new Promise(function(resolve, reject) {7 var channel = new MessageChannel();8 channel.port1.onmessage = function(e) {9 if (e.data === 'writeable start') {10 resolve();11 }12 };13 navigator.serviceWorker.controller.postMessage('writeable start', [channel.port2]);14 });15 }16};17self.addEventListener('message', function(e) {18 if (e.data === 'writeable start') {19 e.ports[0].postMessage('writeable start');20 }21});22 if ('serviceWorker' in navigator) {23 navigator.serviceWorker.register('/service-worker.js');24 }
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LambdaTest Learning Hubs:
- JUnit Tutorial
- TestNG Tutorial
- Webdriver Tutorial
- WebDriverIO Tutorial
- Protractor Tutorial
- Selenium 4 Tutorial
- Jenkins Tutorial
- NUnit Tutorial
- Jest Tutorial
- Playwright Tutorial
- Cypress Tutorial
- PyTest Tutorial
YouTube
You could also refer to video tutorials over LambdaTest YouTube channel to get step by step demonstration from industry experts.
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