How to use ReadableStreamTee method in wpt

Best JavaScript code snippet using wpt

aflprep_tee.any.js

Source:aflprep_tee.any.js

1'use strict';2test(() => {3  const rs = new ReadableStream();4  const result = rs.tee();5  assert_true(Array.isArray(result), 'return value should be an array');6  assert_equals(result.length, 2, 'array should have length 2');7  assert_equals(result[0].constructor, ReadableStream, '0th element should be a ReadableStream');8  assert_equals(result[1].constructor, ReadableStream, '1st element should be a ReadableStream');9}, 'ReadableStream teeing: rs.tee() returns an array of two ReadableStreams');10promise_test(t => {11  const rs = new ReadableStream({12    start(c) {13      c.enqueue('a');14      c.enqueue('b');15      c.close();16    }17  });18  const branch = rs.tee();19  const branch1 = branch[0];20  const branch2 = branch[1];21  const reader1 = branch1.getReader();22  const reader2 = branch2.getReader();23  reader2.closed.then(t.unreached_func('branch2 should not be closed'));24  return Promise.all([25    reader1.closed,26    reader1.read().then(r => {27      assert_object_equals(r, { value: 'a', done: false }, 'first chunk from branch1 should be correct');28    }),29    reader1.read().then(r => {30      assert_object_equals(r, { value: 'b', done: false }, 'second chunk from branch1 should be correct');31    }),32    reader1.read().then(r => {33      assert_object_equals(r, { value: undefined, done: true }, 'third read() from branch1 should be done');34    }),35    reader2.read().then(r => {36      assert_object_equals(r, { value: 'a', done: false }, 'first chunk from branch2 should be correct');37    })38  ]);39}, 'ReadableStream teeing: should be able to read one branch to the end without affecting the other');40promise_test(() => {41  const theObject = { the: 'test object' };42  const rs = new ReadableStream({43    start(c) {44      c.enqueue(theObject);45    }46  });47  const branch = rs.tee();48  const branch1 = branch[0];49  const branch2 = branch[1];50  const reader1 = branch1.getReader();51  const reader2 = branch2.getReader();52  return Promise.all([reader1.read(), reader2.read()]).then(values => {53    assert_object_equals(values[0], values[1], 'the values should be equal');54  });55}, 'ReadableStream teeing: values should be equal across each branch');56promise_test(t => {57  const theError = { name: 'boo!' };58  const rs = new ReadableStream({59    start(c) {60      c.enqueue('a');61      c.enqueue('b');62    },63    pull() {64      throw theError;65    }66  });67  const branches = rs.tee();68  const reader1 = branches[0].getReader();69  const reader2 = branches[1].getReader();70  reader1.label = 'reader1';71  reader2.label = 'reader2';72  return Promise.all([73    promise_rejects_exactly(t, theError, reader1.closed),74    promise_rejects_exactly(t, theError, reader2.closed),75    reader1.read().then(r => {76      assert_object_equals(r, { value: 'a', done: false }, 'should be able to read the first chunk in branch1');77    }),78    reader1.read().then(r => {79      assert_object_equals(r, { value: 'b', done: false }, 'should be able to read the second chunk in branch1');80      return promise_rejects_exactly(t, theError, reader2.read());81    })82    .then(() => promise_rejects_exactly(t, theError, reader1.read()))83  ]);84}, 'ReadableStream teeing: errors in the source should propagate to both branches');85promise_test(() => {86  const rs = new ReadableStream({87    start(c) {88      c.enqueue('a');89      c.enqueue('b');90      c.close();91    }92  });93  const branches = rs.tee();94  const branch1 = branches[0];95  const branch2 = branches[1];96  branch1.cancel();97  return Promise.all([98    readableStreamToArray(branch1).then(chunks => {99      assert_array_equals(chunks, [], 'branch1 should have no chunks');100    }),101    readableStreamToArray(branch2).then(chunks => {102      assert_array_equals(chunks, ['a', 'b'], 'branch2 should have two chunks');103    })104  ]);105}, 'ReadableStream teeing: canceling branch1 should not impact branch2');106promise_test(() => {107  const rs = new ReadableStream({108    start(c) {109      c.enqueue('a');110      c.enqueue('b');111      c.close();112    }113  });114  const branches = rs.tee();115  const branch1 = branches[0];116  const branch2 = branches[1];117  branch2.cancel();118  return Promise.all([119    readableStreamToArray(branch1).then(chunks => {120      assert_array_equals(chunks, ['a', 'b'], 'branch1 should have two chunks');121    }),122    readableStreamToArray(branch2).then(chunks => {123      assert_array_equals(chunks, [], 'branch2 should have no chunks');124    })125  ]);126}, 'ReadableStream teeing: canceling branch2 should not impact branch1');127promise_test(() => {128  const reason1 = new Error('We\'re wanted men.');129  const reason2 = new Error('I have the death sentence on twelve systems.');130  let resolve;131  const promise = new Promise(r => resolve = r);132  const rs = new ReadableStream({133    cancel(reason) {134      assert_array_equals(reason, [reason1, reason2],135                          'the cancel reason should be an array containing those from the branches');136      resolve();137    }138  });139  const branch = rs.tee();140  const branch1 = branch[0];141  const branch2 = branch[1];142  branch1.cancel(reason1);143  branch2.cancel(reason2);144  return promise;145}, 'ReadableStream teeing: canceling both branches should aggregate the cancel reasons into an array');146promise_test(() => {147  const reason1 = new Error('This little one\'s not worth the effort.');148  const reason2 = new Error('Come, let me get you something.');149  let resolve;150  const promise = new Promise(r => resolve = r);151  const rs = new ReadableStream({152    cancel(reason) {153      assert_array_equals(reason, [reason1, reason2],154                          'the cancel reason should be an array containing those from the branches');155      resolve();156    }157  });158  const branch = rs.tee();159  const branch1 = branch[0];160  const branch2 = branch[1];161  return Promise.all([162    branch2.cancel(reason2),163    branch1.cancel(reason1),164    promise165  ]);166}, 'ReadableStream teeing: canceling both branches in reverse order should aggregate the cancel reasons into an array');167promise_test(t => {168  const theError = { name: 'I\'ll be careful.' };169  const rs = new ReadableStream({170    cancel() {171      throw theError;172    }173  });174  const branch = rs.tee();175  const branch1 = branch[0];176  const branch2 = branch[1];177  return Promise.all([178    promise_rejects_exactly(t, theError, branch1.cancel()),179    promise_rejects_exactly(t, theError, branch2.cancel())180  ]);181}, 'ReadableStream teeing: failing to cancel the original stream should cause cancel() to reject on branches');182promise_test(t => {183  const theError = { name: 'You just watch yourself!' };184  let controller;185  const stream = new ReadableStream({ start(c) { controller = c; } });186  const [branch1, branch2] = stream.tee();187  controller.error(theError);188  return Promise.all([189    promise_rejects_exactly(t, theError, branch1.cancel()),190    promise_rejects_exactly(t, theError, branch2.cancel())191  ]);192}, 'ReadableStream teeing: erroring a teed stream should properly handle canceled branches');193promise_test(t => {194  let controller;195  const stream = new ReadableStream({ start(c) { controller = c; } });196  const [branch1, branch2] = stream.tee();197  const error = new Error();198  error.name = 'distinctive';199  controller.enqueue();200  controller.enqueue();201  return delay(0).then(() => {202    controller.error(error);203    const reader1 = branch1.getReader();204    const reader2 = branch2.getReader();205    return Promise.all([206      promise_rejects_exactly(t, error, reader1.closed, 'reader1.closed should reject'),207      promise_rejects_exactly(t, error, reader2.closed, 'reader2.closed should reject')208    ]);209  });210}, 'ReadableStream teeing: erroring a teed stream should error both branches');211promise_test(() => {212  let controller;213  const rs = new ReadableStream({214    start(c) {215      controller = c;216    }217  });218  const branches = rs.tee();219  const reader1 = branches[0].getReader();220  const reader2 = branches[1].getReader();221  const promise = Promise.all([reader1.closed, reader2.closed]);222  controller.close();223  return promise;224}, 'ReadableStream teeing: closing the original should immediately close the branches');225promise_test(t => {226  let controller;227  const rs = new ReadableStream({228    start(c) {229      controller = c;230    }231  });232  const branches = rs.tee();233  const reader1 = branches[0].getReader();234  const reader2 = branches[1].getReader();235  const theError = { name: 'boo!' };236  const promise = Promise.all([237    promise_rejects_exactly(t, theError, reader1.closed),238    promise_rejects_exactly(t, theError, reader2.closed)239  ]);240  controller.error(theError);241  return promise;242}, 'ReadableStream teeing: erroring the original should immediately error the branches');243promise_test(async t => {244  let controller;245  const rs = new ReadableStream({246    start(c) {247      controller = c;248    }249  });250  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());251  const cancelPromise = reader2.cancel();252  controller.enqueue('a');253  const read1 = await reader1.read();254  assert_object_equals(read1, { value: 'a', done: false }, 'first read() from branch1 should fulfill with the chunk');255  controller.close();256  const read2 = await reader1.read();257  assert_object_equals(read2, { value: undefined, done: true }, 'second read() from branch1 should be done');258  await Promise.all([259    reader1.closed,260    cancelPromise261  ]);262}, 'ReadableStream teeing: canceling branch1 should finish when branch2 reads until end of stream');263promise_test(async t => {264  let controller;265  const theError = { name: 'boo!' };266  const rs = new ReadableStream({267    start(c) {268      controller = c;269    }270  });271  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());272  const cancelPromise = reader2.cancel();273  controller.error(theError);274  await Promise.all([275    promise_rejects_exactly(t, theError, reader1.read()),276    cancelPromise277  ]);278}, 'ReadableStream teeing: canceling branch1 should finish when original stream errors');279promise_test(async () => {280  const rs = new ReadableStream({});281  const [branch1, branch2] = rs.tee();282  const cancel1 = branch1.cancel();283  await flushAsyncEvents();284  const cancel2 = branch2.cancel();285  await Promise.all([cancel1, cancel2]);286}, 'ReadableStream teeing: canceling both branches in sequence with delay');287promise_test(async t => {288  const theError = { name: 'boo!' };289  const rs = new ReadableStream({290    cancel() {291      throw theError;292    }293  });294  const [branch1, branch2] = rs.tee();295  const cancel1 = branch1.cancel();296  await flushAsyncEvents();297  const cancel2 = branch2.cancel();298  await Promise.all([299    promise_rejects_exactly(t, theError, cancel1),300    promise_rejects_exactly(t, theError, cancel2)301  ]);302}, 'ReadableStream teeing: failing to cancel when canceling both branches in sequence with delay');303test(t => {304  const oldReadableStream = ReadableStream;305  const getReader = ReadableStream.prototype.getReader;306  const origRS = new ReadableStream();307  ReadableStream = function() {308    throw new Error('global ReadableStream constructor called');309  };310  t.add_cleanup(() => {311    ReadableStream = oldReadableStream;312  });313  const [rs1, rs2] = origRS.tee();314  assert_not_equals(getReader.call(rs1), undefined, 'getReader should work on rs1');315  assert_not_equals(getReader.call(rs2), undefined, 'getReader should work on rs2');316}, 'ReadableStreamTee should not use a modified ReadableStream constructor from the global object');317promise_test(t => {318  const rs = recordingReadableStream({}, { highWaterMark: 0 });319  rs.tee();320  return flushAsyncEvents().then(() => {321    assert_array_equals(rs.events, ['pull'], 'pull should only be called once');322  });323}, 'ReadableStreamTee should not pull more chunks than can fit in the branch queue');324promise_test(t => {325  const rs = recordingReadableStream({326    pull(controller) {327      controller.enqueue('a');328    }329  }, { highWaterMark: 0 });330  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());331  return Promise.all([reader1.read(), reader2.read()])332      .then(() => {333    assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');334  });335}, 'ReadableStreamTee should only pull enough to fill the emptiest queue');336promise_test(t => {337  const rs = recordingReadableStream({}, { highWaterMark: 0 });338  const theError = { name: 'boo!' };339  rs.controller.error(theError);340  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());341  return flushAsyncEvents().then(() => {342    assert_array_equals(rs.events, [], 'pull should not be called');343    return Promise.all([344      promise_rejects_exactly(t, theError, reader1.closed),345      promise_rejects_exactly(t, theError, reader2.closed)346    ]);347  });348}, 'ReadableStreamTee should not pull when original is already errored');349for (const branch of [1, 2]) {350  promise_test(t => {351    const rs = recordingReadableStream({}, { highWaterMark: 0 });352    const theError = { name: 'boo!' };353    const [reader1, reader2] = rs.tee().map(branch => branch.getReader());354    return flushAsyncEvents().then(() => {355      assert_array_equals(rs.events, ['pull'], 'pull should be called once');356      rs.controller.enqueue('a');357      const reader = (branch === 1) ? reader1 : reader2;358      return reader.read();359    }).then(() => flushAsyncEvents()).then(() => {360      assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');361      rs.controller.error(theError);362      return Promise.all([363        promise_rejects_exactly(t, theError, reader1.closed),364        promise_rejects_exactly(t, theError, reader2.closed)365      ]);366    }).then(() => flushAsyncEvents()).then(() => {367      assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');368    });369  }, `ReadableStreamTee stops pulling when original stream errors while branch ${branch} is reading`);370}371promise_test(t => {372  const rs = recordingReadableStream({}, { highWaterMark: 0 });373  const theError = { name: 'boo!' };374  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());375  return flushAsyncEvents().then(() => {376    assert_array_equals(rs.events, ['pull'], 'pull should be called once');377    rs.controller.enqueue('a');378    return Promise.all([reader1.read(), reader2.read()]);379  }).then(() => flushAsyncEvents()).then(() => {380    assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');381    rs.controller.error(theError);382    return Promise.all([383      promise_rejects_exactly(t, theError, reader1.closed),384      promise_rejects_exactly(t, theError, reader2.closed)385    ]);386  }).then(() => flushAsyncEvents()).then(() => {387    assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');388  });...

tee.any.js

Source:tee.any.js

1// META: global=window,worker,jsshell2// META: script=../resources/rs-utils.js3// META: script=../resources/test-utils.js4// META: script=../resources/recording-streams.js5'use strict';6test(() => {7  const rs = new ReadableStream();8  const result = rs.tee();9  assert_true(Array.isArray(result), 'return value should be an array');10  assert_equals(result.length, 2, 'array should have length 2');11  assert_equals(result[0].constructor, ReadableStream, '0th element should be a ReadableStream');12  assert_equals(result[1].constructor, ReadableStream, '1st element should be a ReadableStream');13}, 'ReadableStream teeing: rs.tee() returns an array of two ReadableStreams');14promise_test(t => {15  const rs = new ReadableStream({16    start(c) {17      c.enqueue('a');18      c.enqueue('b');19      c.close();20    }21  });22  const branch = rs.tee();23  const branch1 = branch[0];24  const branch2 = branch[1];25  const reader1 = branch1.getReader();26  const reader2 = branch2.getReader();27  reader2.closed.then(t.unreached_func('branch2 should not be closed'));28  return Promise.all([29    reader1.closed,30    reader1.read().then(r => {31      assert_object_equals(r, { value: 'a', done: false }, 'first chunk from branch1 should be correct');32    }),33    reader1.read().then(r => {34      assert_object_equals(r, { value: 'b', done: false }, 'second chunk from branch1 should be correct');35    }),36    reader1.read().then(r => {37      assert_object_equals(r, { value: undefined, done: true }, 'third read() from branch1 should be done');38    }),39    reader2.read().then(r => {40      assert_object_equals(r, { value: 'a', done: false }, 'first chunk from branch2 should be correct');41    })42  ]);43}, 'ReadableStream teeing: should be able to read one branch to the end without affecting the other');44promise_test(() => {45  const theObject = { the: 'test object' };46  const rs = new ReadableStream({47    start(c) {48      c.enqueue(theObject);49    }50  });51  const branch = rs.tee();52  const branch1 = branch[0];53  const branch2 = branch[1];54  const reader1 = branch1.getReader();55  const reader2 = branch2.getReader();56  return Promise.all([reader1.read(), reader2.read()]).then(values => {57    assert_object_equals(values[0], values[1], 'the values should be equal');58  });59}, 'ReadableStream teeing: values should be equal across each branch');60promise_test(t => {61  const theError = { name: 'boo!' };62  const rs = new ReadableStream({63    start(c) {64      c.enqueue('a');65      c.enqueue('b');66    },67    pull() {68      throw theError;69    }70  });71  const branches = rs.tee();72  const reader1 = branches[0].getReader();73  const reader2 = branches[1].getReader();74  reader1.label = 'reader1';75  reader2.label = 'reader2';76  return Promise.all([77    promise_rejects_exactly(t, theError, reader1.closed),78    promise_rejects_exactly(t, theError, reader2.closed),79    reader1.read().then(r => {80      assert_object_equals(r, { value: 'a', done: false }, 'should be able to read the first chunk in branch1');81    }),82    reader1.read().then(r => {83      assert_object_equals(r, { value: 'b', done: false }, 'should be able to read the second chunk in branch1');84      return promise_rejects_exactly(t, theError, reader2.read());85    })86    .then(() => promise_rejects_exactly(t, theError, reader1.read()))87  ]);88}, 'ReadableStream teeing: errors in the source should propagate to both branches');89promise_test(() => {90  const rs = new ReadableStream({91    start(c) {92      c.enqueue('a');93      c.enqueue('b');94      c.close();95    }96  });97  const branches = rs.tee();98  const branch1 = branches[0];99  const branch2 = branches[1];100  branch1.cancel();101  return Promise.all([102    readableStreamToArray(branch1).then(chunks => {103      assert_array_equals(chunks, [], 'branch1 should have no chunks');104    }),105    readableStreamToArray(branch2).then(chunks => {106      assert_array_equals(chunks, ['a', 'b'], 'branch2 should have two chunks');107    })108  ]);109}, 'ReadableStream teeing: canceling branch1 should not impact branch2');110promise_test(() => {111  const rs = new ReadableStream({112    start(c) {113      c.enqueue('a');114      c.enqueue('b');115      c.close();116    }117  });118  const branches = rs.tee();119  const branch1 = branches[0];120  const branch2 = branches[1];121  branch2.cancel();122  return Promise.all([123    readableStreamToArray(branch1).then(chunks => {124      assert_array_equals(chunks, ['a', 'b'], 'branch1 should have two chunks');125    }),126    readableStreamToArray(branch2).then(chunks => {127      assert_array_equals(chunks, [], 'branch2 should have no chunks');128    })129  ]);130}, 'ReadableStream teeing: canceling branch2 should not impact branch1');131promise_test(() => {132  const reason1 = new Error('We\'re wanted men.');133  const reason2 = new Error('I have the death sentence on twelve systems.');134  let resolve;135  const promise = new Promise(r => resolve = r);136  const rs = new ReadableStream({137    cancel(reason) {138      assert_array_equals(reason, [reason1, reason2],139                          'the cancel reason should be an array containing those from the branches');140      resolve();141    }142  });143  const branch = rs.tee();144  const branch1 = branch[0];145  const branch2 = branch[1];146  branch1.cancel(reason1);147  branch2.cancel(reason2);148  return promise;149}, 'ReadableStream teeing: canceling both branches should aggregate the cancel reasons into an array');150promise_test(() => {151  const reason1 = new Error('This little one\'s not worth the effort.');152  const reason2 = new Error('Come, let me get you something.');153  let resolve;154  const promise = new Promise(r => resolve = r);155  const rs = new ReadableStream({156    cancel(reason) {157      assert_array_equals(reason, [reason1, reason2],158                          'the cancel reason should be an array containing those from the branches');159      resolve();160    }161  });162  const branch = rs.tee();163  const branch1 = branch[0];164  const branch2 = branch[1];165  return Promise.all([166    branch2.cancel(reason2),167    branch1.cancel(reason1),168    promise169  ]);170}, 'ReadableStream teeing: canceling both branches in reverse order should aggregate the cancel reasons into an array');171promise_test(t => {172  const theError = { name: 'I\'ll be careful.' };173  const rs = new ReadableStream({174    cancel() {175      throw theError;176    }177  });178  const branch = rs.tee();179  const branch1 = branch[0];180  const branch2 = branch[1];181  return Promise.all([182    promise_rejects_exactly(t, theError, branch1.cancel()),183    promise_rejects_exactly(t, theError, branch2.cancel())184  ]);185}, 'ReadableStream teeing: failing to cancel the original stream should cause cancel() to reject on branches');186test(() => {187  let controller;188  const stream = new ReadableStream({ start(c) { controller = c; } });189  const [branch1, branch2] = stream.tee();190  controller.error("error");191  branch1.cancel().catch(_=>_);192  branch2.cancel().catch(_=>_);193}, 'ReadableStream teeing: erroring a teed stream should properly handle canceled branches');194promise_test(t => {195  let controller;196  const stream = new ReadableStream({ start(c) { controller = c; } });197  const [branch1, branch2] = stream.tee();198  const error = new Error();199  error.name = 'distinctive';200  // Ensure neither branch is waiting in ReadableStreamDefaultReaderRead().201  controller.enqueue();202  controller.enqueue();203  return delay(0).then(() => {204    // This error will have to be detected via [[closedPromise]].205    controller.error(error);206    const reader1 = branch1.getReader();207    const reader2 = branch2.getReader();208    return Promise.all([209      promise_rejects_exactly(t, error, reader1.closed, 'reader1.closed should reject'),210      promise_rejects_exactly(t, error, reader2.closed, 'reader2.closed should reject')211    ]);212  });213}, 'ReadableStream teeing: erroring a teed stream should error both branches');214promise_test(() => {215  let controller;216  const rs = new ReadableStream({217    start(c) {218      controller = c;219    }220  });221  const branches = rs.tee();222  const reader1 = branches[0].getReader();223  const reader2 = branches[1].getReader();224  const promise = Promise.all([reader1.closed, reader2.closed]);225  controller.close();226  return promise;227}, 'ReadableStream teeing: closing the original should immediately close the branches');228promise_test(t => {229  let controller;230  const rs = new ReadableStream({231    start(c) {232      controller = c;233    }234  });235  const branches = rs.tee();236  const reader1 = branches[0].getReader();237  const reader2 = branches[1].getReader();238  const theError = { name: 'boo!' };239  const promise = Promise.all([240    promise_rejects_exactly(t, theError, reader1.closed),241    promise_rejects_exactly(t, theError, reader2.closed)242  ]);243  controller.error(theError);244  return promise;245}, 'ReadableStream teeing: erroring the original should immediately error the branches');246promise_test(async t => {247  let controller;248  const rs = new ReadableStream({249    start(c) {250      controller = c;251    }252  });253  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());254  const cancelPromise = reader2.cancel();255  controller.enqueue('a');256  const read1 = await reader1.read();257  assert_object_equals(read1, { value: 'a', done: false }, 'first read() from branch1 should fulfill with the chunk');258  controller.close();259  const read2 = await reader1.read();260  assert_object_equals(read2, { value: undefined, done: true }, 'second read() from branch1 should be done');261  await Promise.all([262    reader1.closed,263    cancelPromise264  ]);265}, 'ReadableStream teeing: canceling branch1 should finish when branch2 reads until end of stream');266promise_test(async t => {267  let controller;268  const theError = { name: 'boo!' };269  const rs = new ReadableStream({270    start(c) {271      controller = c;272    }273  });274  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());275  const cancelPromise = reader2.cancel();276  controller.error(theError);277  await Promise.all([278    promise_rejects_exactly(t, theError, reader1.read()),279    cancelPromise280  ]);281}, 'ReadableStream teeing: canceling branch1 should finish when original stream errors');282test(t => {283  // Copy original global.284  const oldReadableStream = ReadableStream;285  const getReader = ReadableStream.prototype.getReader;286  const origRS = new ReadableStream();287  // Replace the global ReadableStream constructor with one that doesn't work.288  ReadableStream = function() {289    throw new Error('global ReadableStream constructor called');290  };291  t.add_cleanup(() => {292    ReadableStream = oldReadableStream;293  });294  // This will probably fail if the global ReadableStream constructor was used.295  const [rs1, rs2] = origRS.tee();296  // These will definitely fail if the global ReadableStream constructor was used.297  assert_not_equals(getReader.call(rs1), undefined, 'getReader should work on rs1');298  assert_not_equals(getReader.call(rs2), undefined, 'getReader should work on rs2');299}, 'ReadableStreamTee should not use a modified ReadableStream constructor from the global object');300promise_test(t => {301  const rs = recordingReadableStream({}, { highWaterMark: 0 });302  // Create two branches, each with a HWM of 1. This should result in one303  // chunk being pulled, not two.304  rs.tee();305  return flushAsyncEvents().then(() => {306    assert_array_equals(rs.events, ['pull'], 'pull should only be called once');307  });308}, 'ReadableStreamTee should not pull more chunks than can fit in the branch queue');309promise_test(t => {310  const rs = recordingReadableStream({311    pull(controller) {312      controller.enqueue('a');313    }314  }, { highWaterMark: 0 });315  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());316  return Promise.all([reader1.read(), reader2.read()])317      .then(() => {318    assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');319  });320}, 'ReadableStreamTee should only pull enough to fill the emptiest queue');321promise_test(t => {322  const rs = recordingReadableStream({}, { highWaterMark: 0 });323  const theError = { name: 'boo!' };324  rs.controller.error(theError);325  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());326  return flushAsyncEvents().then(() => {327    assert_array_equals(rs.events, [], 'pull should not be called');328    return Promise.all([329      promise_rejects_exactly(t, theError, reader1.closed),330      promise_rejects_exactly(t, theError, reader2.closed)331    ]);332  });333}, 'ReadableStreamTee should not pull when original is already errored');334for (const branch of [1, 2]) {335  promise_test(t => {336    const rs = recordingReadableStream({}, { highWaterMark: 0 });337    const theError = { name: 'boo!' };338    const [reader1, reader2] = rs.tee().map(branch => branch.getReader());339    return flushAsyncEvents().then(() => {340      assert_array_equals(rs.events, ['pull'], 'pull should be called once');341      rs.controller.enqueue('a');342      const reader = (branch === 1) ? reader1 : reader2;343      return reader.read();344    }).then(() => flushAsyncEvents()).then(() => {345      assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');346      rs.controller.error(theError);347      return Promise.all([348        promise_rejects_exactly(t, theError, reader1.closed),349        promise_rejects_exactly(t, theError, reader2.closed)350      ]);351    }).then(() => flushAsyncEvents()).then(() => {352      assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');353    });354  }, `ReadableStreamTee stops pulling when original stream errors while branch ${branch} is reading`);355}356promise_test(t => {357  const rs = recordingReadableStream({}, { highWaterMark: 0 });358  const theError = { name: 'boo!' };359  const [reader1, reader2] = rs.tee().map(branch => branch.getReader());360  return flushAsyncEvents().then(() => {361    assert_array_equals(rs.events, ['pull'], 'pull should be called once');362    rs.controller.enqueue('a');363    return Promise.all([reader1.read(), reader2.read()]);364  }).then(() => flushAsyncEvents()).then(() => {365    assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');366    rs.controller.error(theError);367    return Promise.all([368      promise_rejects_exactly(t, theError, reader1.closed),369      promise_rejects_exactly(t, theError, reader2.closed)370    ]);371  }).then(() => flushAsyncEvents()).then(() => {372    assert_array_equals(rs.events, ['pull', 'pull'], 'pull should be called twice');373  });...

Using AI Code Generation

1var rs = new ReadableStream({2  start: function(controller) {3    controller.enqueue('a');4    controller.enqueue('b');5    controller.enqueue('c');6    controller.close();7  }8});9var [branch1, branch2] = rs.tee();10var reader1 = branch1.getReader();11var reader2 = branch2.getReader();12const { ReadableStream, WritableStream, TransformStream, ByteLengthQueuingStrategy, CountQueuingStrategy } = require('web-streams-polyfill/ponyfill');13const rs = new ReadableStream({14  start: function(controller) {15    controller.enqueue('a');16    controller.enqueue('b');17    controller.enqueue('c');18    controller.close();19  }20});21const [branch1, branch2] = rs.tee();22const reader1 = branch1.getReader();23const reader2 = branch2.getReader();

Using AI Code Generation

1var rs = new ReadableStream({2    start(controller) {3        controller.enqueue('a');4        controller.enqueue('b');5        controller.enqueue('c');6        controller.close();7    }8});9var [branch1, branch2] = rs.tee();10var reader1 = branch1.getReader();11var reader2 = branch2.getReader();12const reader = rs.getReader({ mode: "byob" });13const view = new Uint8Array(new ArrayBuffer(2));14const { value, done } = await reader.read(view);15const view = new Uint8Array(new ArrayBuffer(2));16const byobRequest = rs.byobRequest;17byobRequest.respond(1);18const view = new Uint8Array(new ArrayBuffer(2));19const byobRequest = rs.byobRequest;20byobRequest.respondWithNewView(view);21const rs = new ReadableStream({22  start(controller) {23    controller.close();24  }25});26const reader = rs.getReader();27const rs = new ReadableStream({28  start(controller) {29    controller.enqueue("a");30    controller.enqueue("b");31    controller.enqueue("c");32  }33});

Using AI Code Generation

1var rs = new ReadableStream({2  start: function(controller) {3    controller.enqueue("a");4    controller.enqueue("b");5    controller.enqueue("c");6    controller.close();7  }8});9var [branch1, branch2] = rs.tee();10var reader1 = branch1.getReader();11var reader2 = branch2.getReader();12var read1 = reader1.read();13var read2 = reader2.read();14read1.then(function(result1) {15  console.log(result1);16  return read2;17}).then(function(result2) {18  console.log(result2);19  return reader1.read();20}).then(function(result3) {21  console.log(result3);22  return reader2.read();23}).then(function(result4) {24  console.log(result4);25});

Using AI Code Generation

1const { ReadableStream, ReadableStreamTee } = require("streams");2const rs = new ReadableStream({3  start(controller) {4    controller.enqueue("a");5    controller.enqueue("b");6    controller.enqueue("c");7    controller.close();8  }9});10const [branch1, branch2] = ReadableStreamTee(rs);11const reader1 = branch1.getReader();12const reader2 = branch2.getReader();13const { ReadableStream, ReadableStreamTee } = require("streams");14const rs = new ReadableStream({15  start(controller) {16    controller.enqueue("a");17    controller.enqueue("b");18    controller.enqueue("c");19    controller.close();20  }21});22const [branch1, branch2] = ReadableStreamTee(rs);23const reader1 = branch1.getReader();24const reader2 = branch2.getReader();25console.log(reader1

Using AI Code Generation

1import { ReadableStreamTee } from './readable-stream-tee.js';2const rs = new ReadableStream({3  start(controller) {4    console.log('[start]');5    controller.enqueue('a');6    controller.enqueue('b');7    controller.enqueue('c');8  },9  pull(controller) {10    console.log('[pull]');11    controller.enqueue('d');12    controller.close();13  },14  cancel(reason) {15    console.log('[cancel]', reason);16  }17});18const [branch1, branch2] = ReadableStreamTee(rs);19const reader1 = branch1.getReader();20const reader2 = branch2.getReader();21const read1 = reader => {22  reader.read().then(({ value, done }) => {23    if (done) {24      return console.log(`Stream 1 done`);25    }26    console.log(`Stream 1: ${value}`);27    read1(reader);28  });29};30const read2 = reader => {31  reader.read().then(({ value, done }) => {32    if (done) {33      return console.log(`Stream 2 done`);34    }35    console.log(`Stream 2: ${value}`);36    read2(reader);37  });38};39read1(reader1);40read2(reader2);41import { ReadableStreamTee } from './readable-stream-tee.js';42const rs = new ReadableStream({43  start(controller) {44    console.log('[start]');45    controller.enqueue('a');46    controller.enqueue('b');47    controller.enqueue('c');48  },49  pull(controller) {50    console.log('[pull]');51    controller.enqueue('d');52    controller.close();53  },54  cancel(reason) {55    console.log('[cancel]', reason);56  }57});

Using AI Code Generation

1var rs = new ReadableStream({2  start(controller) {3  }4});5var [branch1, branch2] = rs.tee();6var reader1 = branch1.getReader();7var reader2 = branch2.getReader();8var rs = new ReadableStream({9  start(controller) {10  }11});12var [branch1, branch2] = rs.tee();13var reader1 = branch1.getReader();14var reader2 = branch2.getReader();15var rs = new ReadableStream({16  start(controller) {17  }18});19var [branch1, branch2] = rs.tee();20var reader1 = branch1.getReader();21var reader2 = branch2.getReader();22console.log(reader

Using AI Code Generation

1const ReadableStreamTee = require('./readable-stream-tee.js');2const { ReadableStream } = require('./readable-stream.js');3const { WritableStream } = require('./writable-stream.js');4const { CountQueuingStrategy } = require('./count-queuing-strategy.js');5const rs = new ReadableStream({6  start(controller) {7    for (let i = 0; i < 10; ++i) {8      controller.enqueue(i);9    }10    controller.close();11  }12}, new CountQueuingStrategy({ highWaterMark: 5 }));13const [branch1, branch2] = ReadableStreamTee(rs);14const ws1 = new WritableStream({15  write(chunk) {16    console.log(`branch1: ${chunk}`);17  },18  close() {19    console.log('branch1 closed');20  }21});22const ws2 = new WritableStream({23  write(chunk) {24    console.log(`branch2: ${chunk}`);25  },26  close() {27    console.log('branch2 closed');28  }29});30branch1.pipeTo(ws1);31branch2.pipeTo(ws2);

Using AI Code Generation

1var rs = new ReadableStream();2var [branch1, branch2] = rs.tee();3var reader1 = branch1.getReader();4var reader2 = branch2.getReader();5var readAndLog = function(reader) {6  return reader.read().then(function(result) {7    if (result.done) {8      console.log("Stream complete");9      return;10    }11    console.log("Read: " + result.value);12    return readAndLog(reader);13  });14}15readAndLog(reader1);16readAndLog(reader2);

Using AI Code Generation

1import ReadableStreamTee from 'web-streams-polyfill/ponyfill/es6';2import ReadableStream from 'web-streams-polyfill/ponyfill/es6';3import WritableStream from 'web-streams-polyfill/ponyfill/es6';4import CountQueuingStrategy from 'web-streams-polyfill/ponyfill/es6';5import ByteLengthQueuingStrategy from 'web-streams-polyfill/ponyfill/es6';6import ReadableByteStreamController from 'web-streams-polyfill/ponyfill/es6';7const { ReadableStream, WritableStream, CountQueuingStrategy, ByteLengthQueuingStrategy, ReadableByteStreamController } = globalThis;8const start = async () => {9    const rs = new ReadableStream({

Using AI Code Generation

1function testReadableStreamTee() {2  const rs = new ReadableStream({3    start(controller) {4      controller.enqueue('a');5      controller.enqueue('b');6      controller.enqueue('c');7      controller.close();8    }9  });10  const [branch1, branch2] = rs.tee();11  const reader1 = branch1.getReader();12  const reader2 = branch2.getReader();13  let result1 = '';14  let result2 = '';15  const readAll = reader => {16    return reader.read().then(({ done, value }) => {17      if (done) {18        return;19      }20      result1 += value;21      result2 += value;22      return readAll(reader);23    });24  };25  return Promise.all([26    readAll(reader1),27    readAll(reader2)28  ]).then(() => {29    if (result1 === 'abc' && result2 === 'abc') {30      console.log('ReadableStreamTee test passed.');31    } else {32      console.log('ReadableStreamTee test failed.');33    }34  });35}36testReadableStreamTee();

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