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Comparing version 3.6.0 to 4.0.0

lib/internal/streams/add-abort-signal.js

lib/internal/streams/compose.js

lib/internal/streams/duplex.js

lib/internal/streams/duplexify.js

lib/internal/streams/lazy_transform.js

lib/internal/streams/legacy.js

lib/internal/streams/operators.js

lib/internal/streams/passthrough.js

lib/internal/streams/readable.js

lib/internal/streams/transform.js

lib/internal/streams/utils.js

lib/internal/streams/writable.js

lib/internal/validators.js

lib/ours/browser.js

lib/ours/errors.js

lib/ours/index.js

lib/ours/primordials.js

lib/ours/util.js

lib/stream.js

lib/stream/promises.js

140

lib/_stream_duplex.js

		@@ -1,139 +0,3 @@
		// Copyright Joyent, Inc. and other Node contributors.
		//
		// Permission is hereby granted, free of charge, to any person obtaining a
		// copy of this software and associated documentation files (the
		// "Software"), to deal in the Software without restriction, including
		// without limitation the rights to use, copy, modify, merge, publish,
		// distribute, sublicense, and/or sell copies of the Software, and to permit
		// persons to whom the Software is furnished to do so, subject to the
		// following conditions:
		//
		// The above copyright notice and this permission notice shall be included
		// in all copies or substantial portions of the Software.
		//
		// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
		// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
		// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
		// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
		// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
		// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
		// USE OR OTHER DEALINGS IN THE SOFTWARE.
		// a duplex stream is just a stream that is both readable and writable.
		// Since JS doesn't have multiple prototypal inheritance, this class
		// prototypally inherits from Readable, and then parasitically from
		// Writable.
		'use strict';
		/<replacement>/
		'use strict' // Keep this file as an alias for the full stream module.

		var objectKeys = Object.keys \|\| function (obj) {
		var keys = [];

		for (var key in obj) {
		keys.push(key);
		}

		return keys;
		};
		/</replacement>/


		module.exports = Duplex;

		var Readable = require('./_stream_readable');

		var Writable = require('./_stream_writable');

		require('inherits')(Duplex, Readable);

		{
		// Allow the keys array to be GC'ed.
		var keys = objectKeys(Writable.prototype);

		for (var v = 0; v < keys.length; v++) {
		var method = keys[v];
		if (!Duplex.prototype[method]) Duplex.prototype[method] = Writable.prototype[method];
		}
		}

		function Duplex(options) {
		if (!(this instanceof Duplex)) return new Duplex(options);
		Readable.call(this, options);
		Writable.call(this, options);
		this.allowHalfOpen = true;

		if (options) {
		if (options.readable === false) this.readable = false;
		if (options.writable === false) this.writable = false;

		if (options.allowHalfOpen === false) {
		this.allowHalfOpen = false;
		this.once('end', onend);
		}
		}
		}

		Object.defineProperty(Duplex.prototype, 'writableHighWaterMark', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._writableState.highWaterMark;
		}
		});
		Object.defineProperty(Duplex.prototype, 'writableBuffer', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._writableState && this._writableState.getBuffer();
		}
		});
		Object.defineProperty(Duplex.prototype, 'writableLength', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._writableState.length;
		}
		}); // the no-half-open enforcer

		function onend() {
		// If the writable side ended, then we're ok.
		if (this._writableState.ended) return; // no more data can be written.
		// But allow more writes to happen in this tick.

		process.nextTick(onEndNT, this);
		}

		function onEndNT(self) {
		self.end();
		}

		Object.defineProperty(Duplex.prototype, 'destroyed', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		if (this._readableState === undefined \|\| this._writableState === undefined) {
		return false;
		}

		return this._readableState.destroyed && this._writableState.destroyed;
		},
		set: function set(value) {
		// we ignore the value if the stream
		// has not been initialized yet
		if (this._readableState === undefined \|\| this._writableState === undefined) {
		return;
		} // backward compatibility, the user is explicitly
		// managing destroyed


		this._readableState.destroyed = value;
		this._writableState.destroyed = value;
		}
		});
		module.exports = require('./stream').Duplex

lib/_stream_passthrough.js

		@@ -1,39 +0,3 @@
		// Copyright Joyent, Inc. and other Node contributors.
		//
		// Permission is hereby granted, free of charge, to any person obtaining a
		// copy of this software and associated documentation files (the
		// "Software"), to deal in the Software without restriction, including
		// without limitation the rights to use, copy, modify, merge, publish,
		// distribute, sublicense, and/or sell copies of the Software, and to permit
		// persons to whom the Software is furnished to do so, subject to the
		// following conditions:
		//
		// The above copyright notice and this permission notice shall be included
		// in all copies or substantial portions of the Software.
		//
		// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
		// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
		// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
		// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
		// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
		// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
		// USE OR OTHER DEALINGS IN THE SOFTWARE.
		// a passthrough stream.
		// basically just the most minimal sort of Transform stream.
		// Every written chunk gets output as-is.
		'use strict';
		'use strict' // Keep this file as an alias for the full stream module.

		module.exports = PassThrough;

		var Transform = require('./_stream_transform');

		require('inherits')(PassThrough, Transform);

		function PassThrough(options) {
		if (!(this instanceof PassThrough)) return new PassThrough(options);
		Transform.call(this, options);
		}

		PassThrough.prototype._transform = function (chunk, encoding, cb) {
		cb(null, chunk);
		};
		module.exports = require('./stream').PassThrough

1125

lib/_stream_readable.js

		@@ -1,1124 +0,3 @@
		// Copyright Joyent, Inc. and other Node contributors.
		//
		// Permission is hereby granted, free of charge, to any person obtaining a
		// copy of this software and associated documentation files (the
		// "Software"), to deal in the Software without restriction, including
		// without limitation the rights to use, copy, modify, merge, publish,
		// distribute, sublicense, and/or sell copies of the Software, and to permit
		// persons to whom the Software is furnished to do so, subject to the
		// following conditions:
		//
		// The above copyright notice and this permission notice shall be included
		// in all copies or substantial portions of the Software.
		//
		// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
		// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
		// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
		// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
		// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
		// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
		// USE OR OTHER DEALINGS IN THE SOFTWARE.
		'use strict';
		'use strict' // Keep this file as an alias for the full stream module.

		module.exports = Readable;
		/<replacement>/

		var Duplex;
		/</replacement>/

		Readable.ReadableState = ReadableState;
		/<replacement>/

		var EE = require('events').EventEmitter;

		var EElistenerCount = function EElistenerCount(emitter, type) {
		return emitter.listeners(type).length;
		};
		/</replacement>/

		/<replacement>/


		var Stream = require('./internal/streams/stream');
		/</replacement>/


		var Buffer = require('buffer').Buffer;

		var OurUint8Array = global.Uint8Array \|\| function () {};

		function _uint8ArrayToBuffer(chunk) {
		return Buffer.from(chunk);
		}

		function _isUint8Array(obj) {
		return Buffer.isBuffer(obj) \|\| obj instanceof OurUint8Array;
		}
		/<replacement>/


		var debugUtil = require('util');

		var debug;

		if (debugUtil && debugUtil.debuglog) {
		debug = debugUtil.debuglog('stream');
		} else {
		debug = function debug() {};
		}
		/</replacement>/


		var BufferList = require('./internal/streams/buffer_list');

		var destroyImpl = require('./internal/streams/destroy');

		var _require = require('./internal/streams/state'),
		getHighWaterMark = _require.getHighWaterMark;

		var _require$codes = require('../errors').codes,
		ERR_INVALID_ARG_TYPE = _require$codes.ERR_INVALID_ARG_TYPE,
		ERR_STREAM_PUSH_AFTER_EOF = _require$codes.ERR_STREAM_PUSH_AFTER_EOF,
		ERR_METHOD_NOT_IMPLEMENTED = _require$codes.ERR_METHOD_NOT_IMPLEMENTED,
		ERR_STREAM_UNSHIFT_AFTER_END_EVENT = _require$codes.ERR_STREAM_UNSHIFT_AFTER_END_EVENT; // Lazy loaded to improve the startup performance.


		var StringDecoder;
		var createReadableStreamAsyncIterator;
		var from;

		require('inherits')(Readable, Stream);

		var errorOrDestroy = destroyImpl.errorOrDestroy;
		var kProxyEvents = ['error', 'close', 'destroy', 'pause', 'resume'];

		function prependListener(emitter, event, fn) {
		// Sadly this is not cacheable as some libraries bundle their own
		// event emitter implementation with them.
		if (typeof emitter.prependListener === 'function') return emitter.prependListener(event, fn); // This is a hack to make sure that our error handler is attached before any
		// userland ones. NEVER DO THIS. This is here only because this code needs
		// to continue to work with older versions of Node.js that do not include
		// the prependListener() method. The goal is to eventually remove this hack.

		if (!emitter._events \|\| !emitter._events[event]) emitter.on(event, fn);else if (Array.isArray(emitter._events[event])) emitter._events[event].unshift(fn);else emitter._events[event] = [fn, emitter._events[event]];
		}

		function ReadableState(options, stream, isDuplex) {
		Duplex = Duplex \|\| require('./_stream_duplex');
		options = options \|\| {}; // Duplex streams are both readable and writable, but share
		// the same options object.
		// However, some cases require setting options to different
		// values for the readable and the writable sides of the duplex stream.
		// These options can be provided separately as readableXXX and writableXXX.

		if (typeof isDuplex !== 'boolean') isDuplex = stream instanceof Duplex; // object stream flag. Used to make read(n) ignore n and to
		// make all the buffer merging and length checks go away

		this.objectMode = !!options.objectMode;
		if (isDuplex) this.objectMode = this.objectMode \|\| !!options.readableObjectMode; // the point at which it stops calling _read() to fill the buffer
		// Note: 0 is a valid value, means "don't call _read preemptively ever"

		this.highWaterMark = getHighWaterMark(this, options, 'readableHighWaterMark', isDuplex); // A linked list is used to store data chunks instead of an array because the
		// linked list can remove elements from the beginning faster than
		// array.shift()

		this.buffer = new BufferList();
		this.length = 0;
		this.pipes = null;
		this.pipesCount = 0;
		this.flowing = null;
		this.ended = false;
		this.endEmitted = false;
		this.reading = false; // a flag to be able to tell if the event 'readable'/'data' is emitted
		// immediately, or on a later tick. We set this to true at first, because
		// any actions that shouldn't happen until "later" should generally also
		// not happen before the first read call.

		this.sync = true; // whenever we return null, then we set a flag to say
		// that we're awaiting a 'readable' event emission.

		this.needReadable = false;
		this.emittedReadable = false;
		this.readableListening = false;
		this.resumeScheduled = false;
		this.paused = true; // Should close be emitted on destroy. Defaults to true.

		this.emitClose = options.emitClose !== false; // Should .destroy() be called after 'end' (and potentially 'finish')

		this.autoDestroy = !!options.autoDestroy; // has it been destroyed

		this.destroyed = false; // Crypto is kind of old and crusty. Historically, its default string
		// encoding is 'binary' so we have to make this configurable.
		// Everything else in the universe uses 'utf8', though.

		this.defaultEncoding = options.defaultEncoding \|\| 'utf8'; // the number of writers that are awaiting a drain event in .pipe()s

		this.awaitDrain = 0; // if true, a maybeReadMore has been scheduled

		this.readingMore = false;
		this.decoder = null;
		this.encoding = null;

		if (options.encoding) {
		if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder;
		this.decoder = new StringDecoder(options.encoding);
		this.encoding = options.encoding;
		}
		}

		function Readable(options) {
		Duplex = Duplex \|\| require('./_stream_duplex');
		if (!(this instanceof Readable)) return new Readable(options); // Checking for a Stream.Duplex instance is faster here instead of inside
		// the ReadableState constructor, at least with V8 6.5

		var isDuplex = this instanceof Duplex;
		this._readableState = new ReadableState(options, this, isDuplex); // legacy

		this.readable = true;

		if (options) {
		if (typeof options.read === 'function') this._read = options.read;
		if (typeof options.destroy === 'function') this._destroy = options.destroy;
		}

		Stream.call(this);
		}

		Object.defineProperty(Readable.prototype, 'destroyed', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		if (this._readableState === undefined) {
		return false;
		}

		return this._readableState.destroyed;
		},
		set: function set(value) {
		// we ignore the value if the stream
		// has not been initialized yet
		if (!this._readableState) {
		return;
		} // backward compatibility, the user is explicitly
		// managing destroyed


		this._readableState.destroyed = value;
		}
		});
		Readable.prototype.destroy = destroyImpl.destroy;
		Readable.prototype._undestroy = destroyImpl.undestroy;

		Readable.prototype._destroy = function (err, cb) {
		cb(err);
		}; // Manually shove something into the read() buffer.
		// This returns true if the highWaterMark has not been hit yet,
		// similar to how Writable.write() returns true if you should
		// write() some more.


		Readable.prototype.push = function (chunk, encoding) {
		var state = this._readableState;
		var skipChunkCheck;

		if (!state.objectMode) {
		if (typeof chunk === 'string') {
		encoding = encoding \|\| state.defaultEncoding;

		if (encoding !== state.encoding) {
		chunk = Buffer.from(chunk, encoding);
		encoding = '';
		}

		skipChunkCheck = true;
		}
		} else {
		skipChunkCheck = true;
		}

		return readableAddChunk(this, chunk, encoding, false, skipChunkCheck);
		}; // Unshift should always be something directly out of read()


		Readable.prototype.unshift = function (chunk) {
		return readableAddChunk(this, chunk, null, true, false);
		};

		function readableAddChunk(stream, chunk, encoding, addToFront, skipChunkCheck) {
		debug('readableAddChunk', chunk);
		var state = stream._readableState;

		if (chunk === null) {
		state.reading = false;
		onEofChunk(stream, state);
		} else {
		var er;
		if (!skipChunkCheck) er = chunkInvalid(state, chunk);

		if (er) {
		errorOrDestroy(stream, er);
		} else if (state.objectMode \|\| chunk && chunk.length > 0) {
		if (typeof chunk !== 'string' && !state.objectMode && Object.getPrototypeOf(chunk) !== Buffer.prototype) {
		chunk = _uint8ArrayToBuffer(chunk);
		}

		if (addToFront) {
		if (state.endEmitted) errorOrDestroy(stream, new ERR_STREAM_UNSHIFT_AFTER_END_EVENT());else addChunk(stream, state, chunk, true);
		} else if (state.ended) {
		errorOrDestroy(stream, new ERR_STREAM_PUSH_AFTER_EOF());
		} else if (state.destroyed) {
		return false;
		} else {
		state.reading = false;

		if (state.decoder && !encoding) {
		chunk = state.decoder.write(chunk);
		if (state.objectMode \|\| chunk.length !== 0) addChunk(stream, state, chunk, false);else maybeReadMore(stream, state);
		} else {
		addChunk(stream, state, chunk, false);
		}
		}
		} else if (!addToFront) {
		state.reading = false;
		maybeReadMore(stream, state);
		}
		} // We can push more data if we are below the highWaterMark.
		// Also, if we have no data yet, we can stand some more bytes.
		// This is to work around cases where hwm=0, such as the repl.


		return !state.ended && (state.length < state.highWaterMark \|\| state.length === 0);
		}

		function addChunk(stream, state, chunk, addToFront) {
		if (state.flowing && state.length === 0 && !state.sync) {
		state.awaitDrain = 0;
		stream.emit('data', chunk);
		} else {
		// update the buffer info.
		state.length += state.objectMode ? 1 : chunk.length;
		if (addToFront) state.buffer.unshift(chunk);else state.buffer.push(chunk);
		if (state.needReadable) emitReadable(stream);
		}

		maybeReadMore(stream, state);
		}

		function chunkInvalid(state, chunk) {
		var er;

		if (!_isUint8Array(chunk) && typeof chunk !== 'string' && chunk !== undefined && !state.objectMode) {
		er = new ERR_INVALID_ARG_TYPE('chunk', ['string', 'Buffer', 'Uint8Array'], chunk);
		}

		return er;
		}

		Readable.prototype.isPaused = function () {
		return this._readableState.flowing === false;
		}; // backwards compatibility.


		Readable.prototype.setEncoding = function (enc) {
		if (!StringDecoder) StringDecoder = require('string_decoder/').StringDecoder;
		var decoder = new StringDecoder(enc);
		this._readableState.decoder = decoder; // If setEncoding(null), decoder.encoding equals utf8

		this._readableState.encoding = this._readableState.decoder.encoding; // Iterate over current buffer to convert already stored Buffers:

		var p = this._readableState.buffer.head;
		var content = '';

		while (p !== null) {
		content += decoder.write(p.data);
		p = p.next;
		}

		this._readableState.buffer.clear();

		if (content !== '') this._readableState.buffer.push(content);
		this._readableState.length = content.length;
		return this;
		}; // Don't raise the hwm > 1GB


		var MAX_HWM = 0x40000000;

		function computeNewHighWaterMark(n) {
		if (n >= MAX_HWM) {
		// TODO(ronag): Throw ERR_VALUE_OUT_OF_RANGE.
		n = MAX_HWM;
		} else {
		// Get the next highest power of 2 to prevent increasing hwm excessively in
		// tiny amounts
		n--;
		n \|= n >>> 1;
		n \|= n >>> 2;
		n \|= n >>> 4;
		n \|= n >>> 8;
		n \|= n >>> 16;
		n++;
		}

		return n;
		} // This function is designed to be inlinable, so please take care when making
		// changes to the function body.


		function howMuchToRead(n, state) {
		if (n <= 0 \|\| state.length === 0 && state.ended) return 0;
		if (state.objectMode) return 1;

		if (n !== n) {
		// Only flow one buffer at a time
		if (state.flowing && state.length) return state.buffer.head.data.length;else return state.length;
		} // If we're asking for more than the current hwm, then raise the hwm.


		if (n > state.highWaterMark) state.highWaterMark = computeNewHighWaterMark(n);
		if (n <= state.length) return n; // Don't have enough

		if (!state.ended) {
		state.needReadable = true;
		return 0;
		}

		return state.length;
		} // you can override either this method, or the async _read(n) below.


		Readable.prototype.read = function (n) {
		debug('read', n);
		n = parseInt(n, 10);
		var state = this._readableState;
		var nOrig = n;
		if (n !== 0) state.emittedReadable = false; // if we're doing read(0) to trigger a readable event, but we
		// already have a bunch of data in the buffer, then just trigger
		// the 'readable' event and move on.

		if (n === 0 && state.needReadable && ((state.highWaterMark !== 0 ? state.length >= state.highWaterMark : state.length > 0) \|\| state.ended)) {
		debug('read: emitReadable', state.length, state.ended);
		if (state.length === 0 && state.ended) endReadable(this);else emitReadable(this);
		return null;
		}

		n = howMuchToRead(n, state); // if we've ended, and we're now clear, then finish it up.

		if (n === 0 && state.ended) {
		if (state.length === 0) endReadable(this);
		return null;
		} // All the actual chunk generation logic needs to be
		// below the call to _read. The reason is that in certain
		// synthetic stream cases, such as passthrough streams, _read
		// may be a completely synchronous operation which may change
		// the state of the read buffer, providing enough data when
		// before there was not enough.
		//
		// So, the steps are:
		// 1. Figure out what the state of things will be after we do
		// a read from the buffer.
		//
		// 2. If that resulting state will trigger a _read, then call _read.
		// Note that this may be asynchronous, or synchronous. Yes, it is
		// deeply ugly to write APIs this way, but that still doesn't mean
		// that the Readable class should behave improperly, as streams are
		// designed to be sync/async agnostic.
		// Take note if the _read call is sync or async (ie, if the read call
		// has returned yet), so that we know whether or not it's safe to emit
		// 'readable' etc.
		//
		// 3. Actually pull the requested chunks out of the buffer and return.
		// if we need a readable event, then we need to do some reading.


		var doRead = state.needReadable;
		debug('need readable', doRead); // if we currently have less than the highWaterMark, then also read some

		if (state.length === 0 \|\| state.length - n < state.highWaterMark) {
		doRead = true;
		debug('length less than watermark', doRead);
		} // however, if we've ended, then there's no point, and if we're already
		// reading, then it's unnecessary.


		if (state.ended \|\| state.reading) {
		doRead = false;
		debug('reading or ended', doRead);
		} else if (doRead) {
		debug('do read');
		state.reading = true;
		state.sync = true; // if the length is currently zero, then we need a readable event.

		if (state.length === 0) state.needReadable = true; // call internal read method

		this._read(state.highWaterMark);

		state.sync = false; // If _read pushed data synchronously, then `reading` will be false,
		// and we need to re-evaluate how much data we can return to the user.

		if (!state.reading) n = howMuchToRead(nOrig, state);
		}

		var ret;
		if (n > 0) ret = fromList(n, state);else ret = null;

		if (ret === null) {
		state.needReadable = state.length <= state.highWaterMark;
		n = 0;
		} else {
		state.length -= n;
		state.awaitDrain = 0;
		}

		if (state.length === 0) {
		// If we have nothing in the buffer, then we want to know
		// as soon as we do get something into the buffer.
		if (!state.ended) state.needReadable = true; // If we tried to read() past the EOF, then emit end on the next tick.

		if (nOrig !== n && state.ended) endReadable(this);
		}

		if (ret !== null) this.emit('data', ret);
		return ret;
		};

		function onEofChunk(stream, state) {
		debug('onEofChunk');
		if (state.ended) return;

		if (state.decoder) {
		var chunk = state.decoder.end();

		if (chunk && chunk.length) {
		state.buffer.push(chunk);
		state.length += state.objectMode ? 1 : chunk.length;
		}
		}

		state.ended = true;

		if (state.sync) {
		// if we are sync, wait until next tick to emit the data.
		// Otherwise we risk emitting data in the flow()
		// the readable code triggers during a read() call
		emitReadable(stream);
		} else {
		// emit 'readable' now to make sure it gets picked up.
		state.needReadable = false;

		if (!state.emittedReadable) {
		state.emittedReadable = true;
		emitReadable_(stream);
		}
		}
		} // Don't emit readable right away in sync mode, because this can trigger
		// another read() call => stack overflow. This way, it might trigger
		// a nextTick recursion warning, but that's not so bad.


		function emitReadable(stream) {
		var state = stream._readableState;
		debug('emitReadable', state.needReadable, state.emittedReadable);
		state.needReadable = false;

		if (!state.emittedReadable) {
		debug('emitReadable', state.flowing);
		state.emittedReadable = true;
		process.nextTick(emitReadable_, stream);
		}
		}

		function emitReadable_(stream) {
		var state = stream._readableState;
		debug('emitReadable_', state.destroyed, state.length, state.ended);

		if (!state.destroyed && (state.length \|\| state.ended)) {
		stream.emit('readable');
		state.emittedReadable = false;
		} // The stream needs another readable event if
		// 1. It is not flowing, as the flow mechanism will take
		// care of it.
		// 2. It is not ended.
		// 3. It is below the highWaterMark, so we can schedule
		// another readable later.


		state.needReadable = !state.flowing && !state.ended && state.length <= state.highWaterMark;
		flow(stream);
		} // at this point, the user has presumably seen the 'readable' event,
		// and called read() to consume some data. that may have triggered
		// in turn another _read(n) call, in which case reading = true if
		// it's in progress.
		// However, if we're not ended, or reading, and the length < hwm,
		// then go ahead and try to read some more preemptively.


		function maybeReadMore(stream, state) {
		if (!state.readingMore) {
		state.readingMore = true;
		process.nextTick(maybeReadMore_, stream, state);
		}
		}

		function maybeReadMore_(stream, state) {
		// Attempt to read more data if we should.
		//
		// The conditions for reading more data are (one of):
		// - Not enough data buffered (state.length < state.highWaterMark). The loop
		// is responsible for filling the buffer with enough data if such data
		// is available. If highWaterMark is 0 and we are not in the flowing mode
		// we should _not_ attempt to buffer any extra data. We'll get more data
		// when the stream consumer calls read() instead.
		// - No data in the buffer, and the stream is in flowing mode. In this mode
		// the loop below is responsible for ensuring read() is called. Failing to
		// call read here would abort the flow and there's no other mechanism for
		// continuing the flow if the stream consumer has just subscribed to the
		// 'data' event.
		//
		// In addition to the above conditions to keep reading data, the following
		// conditions prevent the data from being read:
		// - The stream has ended (state.ended).
		// - There is already a pending 'read' operation (state.reading). This is a
		// case where the the stream has called the implementation defined _read()
		// method, but they are processing the call asynchronously and have _not_
		// called push() with new data. In this case we skip performing more
		// read()s. The execution ends in this method again after the _read() ends
		// up calling push() with more data.
		while (!state.reading && !state.ended && (state.length < state.highWaterMark \|\| state.flowing && state.length === 0)) {
		var len = state.length;
		debug('maybeReadMore read 0');
		stream.read(0);
		if (len === state.length) // didn't get any data, stop spinning.
		break;
		}

		state.readingMore = false;
		} // abstract method. to be overridden in specific implementation classes.
		// call cb(er, data) where data is <= n in length.
		// for virtual (non-string, non-buffer) streams, "length" is somewhat
		// arbitrary, and perhaps not very meaningful.


		Readable.prototype._read = function (n) {
		errorOrDestroy(this, new ERR_METHOD_NOT_IMPLEMENTED('_read()'));
		};

		Readable.prototype.pipe = function (dest, pipeOpts) {
		var src = this;
		var state = this._readableState;

		switch (state.pipesCount) {
		case 0:
		state.pipes = dest;
		break;

		case 1:
		state.pipes = [state.pipes, dest];
		break;

		default:
		state.pipes.push(dest);
		break;
		}

		state.pipesCount += 1;
		debug('pipe count=%d opts=%j', state.pipesCount, pipeOpts);
		var doEnd = (!pipeOpts \|\| pipeOpts.end !== false) && dest !== process.stdout && dest !== process.stderr;
		var endFn = doEnd ? onend : unpipe;
		if (state.endEmitted) process.nextTick(endFn);else src.once('end', endFn);
		dest.on('unpipe', onunpipe);

		function onunpipe(readable, unpipeInfo) {
		debug('onunpipe');

		if (readable === src) {
		if (unpipeInfo && unpipeInfo.hasUnpiped === false) {
		unpipeInfo.hasUnpiped = true;
		cleanup();
		}
		}
		}

		function onend() {
		debug('onend');
		dest.end();
		} // when the dest drains, it reduces the awaitDrain counter
		// on the source. This would be more elegant with a .once()
		// handler in flow(), but adding and removing repeatedly is
		// too slow.


		var ondrain = pipeOnDrain(src);
		dest.on('drain', ondrain);
		var cleanedUp = false;

		function cleanup() {
		debug('cleanup'); // cleanup event handlers once the pipe is broken

		dest.removeListener('close', onclose);
		dest.removeListener('finish', onfinish);
		dest.removeListener('drain', ondrain);
		dest.removeListener('error', onerror);
		dest.removeListener('unpipe', onunpipe);
		src.removeListener('end', onend);
		src.removeListener('end', unpipe);
		src.removeListener('data', ondata);
		cleanedUp = true; // if the reader is waiting for a drain event from this
		// specific writer, then it would cause it to never start
		// flowing again.
		// So, if this is awaiting a drain, then we just call it now.
		// If we don't know, then assume that we are waiting for one.

		if (state.awaitDrain && (!dest._writableState \|\| dest._writableState.needDrain)) ondrain();
		}

		src.on('data', ondata);

		function ondata(chunk) {
		debug('ondata');
		var ret = dest.write(chunk);
		debug('dest.write', ret);

		if (ret === false) {
		// If the user unpiped during `dest.write()`, it is possible
		// to get stuck in a permanently paused state if that write
		// also returned false.
		// => Check whether `dest` is still a piping destination.
		if ((state.pipesCount === 1 && state.pipes === dest \|\| state.pipesCount > 1 && indexOf(state.pipes, dest) !== -1) && !cleanedUp) {
		debug('false write response, pause', state.awaitDrain);
		state.awaitDrain++;
		}

		src.pause();
		}
		} // if the dest has an error, then stop piping into it.
		// however, don't suppress the throwing behavior for this.


		function onerror(er) {
		debug('onerror', er);
		unpipe();
		dest.removeListener('error', onerror);
		if (EElistenerCount(dest, 'error') === 0) errorOrDestroy(dest, er);
		} // Make sure our error handler is attached before userland ones.


		prependListener(dest, 'error', onerror); // Both close and finish should trigger unpipe, but only once.

		function onclose() {
		dest.removeListener('finish', onfinish);
		unpipe();
		}

		dest.once('close', onclose);

		function onfinish() {
		debug('onfinish');
		dest.removeListener('close', onclose);
		unpipe();
		}

		dest.once('finish', onfinish);

		function unpipe() {
		debug('unpipe');
		src.unpipe(dest);
		} // tell the dest that it's being piped to


		dest.emit('pipe', src); // start the flow if it hasn't been started already.

		if (!state.flowing) {
		debug('pipe resume');
		src.resume();
		}

		return dest;
		};

		function pipeOnDrain(src) {
		return function pipeOnDrainFunctionResult() {
		var state = src._readableState;
		debug('pipeOnDrain', state.awaitDrain);
		if (state.awaitDrain) state.awaitDrain--;

		if (state.awaitDrain === 0 && EElistenerCount(src, 'data')) {
		state.flowing = true;
		flow(src);
		}
		};
		}

		Readable.prototype.unpipe = function (dest) {
		var state = this._readableState;
		var unpipeInfo = {
		hasUnpiped: false
		}; // if we're not piping anywhere, then do nothing.

		if (state.pipesCount === 0) return this; // just one destination. most common case.

		if (state.pipesCount === 1) {
		// passed in one, but it's not the right one.
		if (dest && dest !== state.pipes) return this;
		if (!dest) dest = state.pipes; // got a match.

		state.pipes = null;
		state.pipesCount = 0;
		state.flowing = false;
		if (dest) dest.emit('unpipe', this, unpipeInfo);
		return this;
		} // slow case. multiple pipe destinations.


		if (!dest) {
		// remove all.
		var dests = state.pipes;
		var len = state.pipesCount;
		state.pipes = null;
		state.pipesCount = 0;
		state.flowing = false;

		for (var i = 0; i < len; i++) {
		dests[i].emit('unpipe', this, {
		hasUnpiped: false
		});
		}

		return this;
		} // try to find the right one.


		var index = indexOf(state.pipes, dest);
		if (index === -1) return this;
		state.pipes.splice(index, 1);
		state.pipesCount -= 1;
		if (state.pipesCount === 1) state.pipes = state.pipes[0];
		dest.emit('unpipe', this, unpipeInfo);
		return this;
		}; // set up data events if they are asked for
		// Ensure readable listeners eventually get something


		Readable.prototype.on = function (ev, fn) {
		var res = Stream.prototype.on.call(this, ev, fn);
		var state = this._readableState;

		if (ev === 'data') {
		// update readableListening so that resume() may be a no-op
		// a few lines down. This is needed to support once('readable').
		state.readableListening = this.listenerCount('readable') > 0; // Try start flowing on next tick if stream isn't explicitly paused

		if (state.flowing !== false) this.resume();
		} else if (ev === 'readable') {
		if (!state.endEmitted && !state.readableListening) {
		state.readableListening = state.needReadable = true;
		state.flowing = false;
		state.emittedReadable = false;
		debug('on readable', state.length, state.reading);

		if (state.length) {
		emitReadable(this);
		} else if (!state.reading) {
		process.nextTick(nReadingNextTick, this);
		}
		}
		}

		return res;
		};

		Readable.prototype.addListener = Readable.prototype.on;

		Readable.prototype.removeListener = function (ev, fn) {
		var res = Stream.prototype.removeListener.call(this, ev, fn);

		if (ev === 'readable') {
		// We need to check if there is someone still listening to
		// readable and reset the state. However this needs to happen
		// after readable has been emitted but before I/O (nextTick) to
		// support once('readable', fn) cycles. This means that calling
		// resume within the same tick will have no
		// effect.
		process.nextTick(updateReadableListening, this);
		}

		return res;
		};

		Readable.prototype.removeAllListeners = function (ev) {
		var res = Stream.prototype.removeAllListeners.apply(this, arguments);

		if (ev === 'readable' \|\| ev === undefined) {
		// We need to check if there is someone still listening to
		// readable and reset the state. However this needs to happen
		// after readable has been emitted but before I/O (nextTick) to
		// support once('readable', fn) cycles. This means that calling
		// resume within the same tick will have no
		// effect.
		process.nextTick(updateReadableListening, this);
		}

		return res;
		};

		function updateReadableListening(self) {
		var state = self._readableState;
		state.readableListening = self.listenerCount('readable') > 0;

		if (state.resumeScheduled && !state.paused) {
		// flowing needs to be set to true now, otherwise
		// the upcoming resume will not flow.
		state.flowing = true; // crude way to check if we should resume
		} else if (self.listenerCount('data') > 0) {
		self.resume();
		}
		}

		function nReadingNextTick(self) {
		debug('readable nexttick read 0');
		self.read(0);
		} // pause() and resume() are remnants of the legacy readable stream API
		// If the user uses them, then switch into old mode.


		Readable.prototype.resume = function () {
		var state = this._readableState;

		if (!state.flowing) {
		debug('resume'); // we flow only if there is no one listening
		// for readable, but we still have to call
		// resume()

		state.flowing = !state.readableListening;
		resume(this, state);
		}

		state.paused = false;
		return this;
		};

		function resume(stream, state) {
		if (!state.resumeScheduled) {
		state.resumeScheduled = true;
		process.nextTick(resume_, stream, state);
		}
		}

		function resume_(stream, state) {
		debug('resume', state.reading);

		if (!state.reading) {
		stream.read(0);
		}

		state.resumeScheduled = false;
		stream.emit('resume');
		flow(stream);
		if (state.flowing && !state.reading) stream.read(0);
		}

		Readable.prototype.pause = function () {
		debug('call pause flowing=%j', this._readableState.flowing);

		if (this._readableState.flowing !== false) {
		debug('pause');
		this._readableState.flowing = false;
		this.emit('pause');
		}

		this._readableState.paused = true;
		return this;
		};

		function flow(stream) {
		var state = stream._readableState;
		debug('flow', state.flowing);

		while (state.flowing && stream.read() !== null) {
		;
		}
		} // wrap an old-style stream as the async data source.
		// This is not part of the readable stream interface.
		// It is an ugly unfortunate mess of history.


		Readable.prototype.wrap = function (stream) {
		var _this = this;

		var state = this._readableState;
		var paused = false;
		stream.on('end', function () {
		debug('wrapped end');

		if (state.decoder && !state.ended) {
		var chunk = state.decoder.end();
		if (chunk && chunk.length) _this.push(chunk);
		}

		_this.push(null);
		});
		stream.on('data', function (chunk) {
		debug('wrapped data');
		if (state.decoder) chunk = state.decoder.write(chunk); // don't skip over falsy values in objectMode

		if (state.objectMode && (chunk === null \|\| chunk === undefined)) return;else if (!state.objectMode && (!chunk \|\| !chunk.length)) return;

		var ret = _this.push(chunk);

		if (!ret) {
		paused = true;
		stream.pause();
		}
		}); // proxy all the other methods.
		// important when wrapping filters and duplexes.

		for (var i in stream) {
		if (this[i] === undefined && typeof stream[i] === 'function') {
		this[i] = function methodWrap(method) {
		return function methodWrapReturnFunction() {
		return stream[method].apply(stream, arguments);
		};
		}(i);
		}
		} // proxy certain important events.


		for (var n = 0; n < kProxyEvents.length; n++) {
		stream.on(kProxyEvents[n], this.emit.bind(this, kProxyEvents[n]));
		} // when we try to consume some more bytes, simply unpause the
		// underlying stream.


		this._read = function (n) {
		debug('wrapped _read', n);

		if (paused) {
		paused = false;
		stream.resume();
		}
		};

		return this;
		};

		if (typeof Symbol === 'function') {
		Readable.prototype[Symbol.asyncIterator] = function () {
		if (createReadableStreamAsyncIterator === undefined) {
		createReadableStreamAsyncIterator = require('./internal/streams/async_iterator');
		}

		return createReadableStreamAsyncIterator(this);
		};
		}

		Object.defineProperty(Readable.prototype, 'readableHighWaterMark', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._readableState.highWaterMark;
		}
		});
		Object.defineProperty(Readable.prototype, 'readableBuffer', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._readableState && this._readableState.buffer;
		}
		});
		Object.defineProperty(Readable.prototype, 'readableFlowing', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._readableState.flowing;
		},
		set: function set(state) {
		if (this._readableState) {
		this._readableState.flowing = state;
		}
		}
		}); // exposed for testing purposes only.

		Readable._fromList = fromList;
		Object.defineProperty(Readable.prototype, 'readableLength', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._readableState.length;
		}
		}); // Pluck off n bytes from an array of buffers.
		// Length is the combined lengths of all the buffers in the list.
		// This function is designed to be inlinable, so please take care when making
		// changes to the function body.

		function fromList(n, state) {
		// nothing buffered
		if (state.length === 0) return null;
		var ret;
		if (state.objectMode) ret = state.buffer.shift();else if (!n \|\| n >= state.length) {
		// read it all, truncate the list
		if (state.decoder) ret = state.buffer.join('');else if (state.buffer.length === 1) ret = state.buffer.first();else ret = state.buffer.concat(state.length);
		state.buffer.clear();
		} else {
		// read part of list
		ret = state.buffer.consume(n, state.decoder);
		}
		return ret;
		}

		function endReadable(stream) {
		var state = stream._readableState;
		debug('endReadable', state.endEmitted);

		if (!state.endEmitted) {
		state.ended = true;
		process.nextTick(endReadableNT, state, stream);
		}
		}

		function endReadableNT(state, stream) {
		debug('endReadableNT', state.endEmitted, state.length); // Check that we didn't get one last unshift.

		if (!state.endEmitted && state.length === 0) {
		state.endEmitted = true;
		stream.readable = false;
		stream.emit('end');

		if (state.autoDestroy) {
		// In case of duplex streams we need a way to detect
		// if the writable side is ready for autoDestroy as well
		var wState = stream._writableState;

		if (!wState \|\| wState.autoDestroy && wState.finished) {
		stream.destroy();
		}
		}
		}
		}

		if (typeof Symbol === 'function') {
		Readable.from = function (iterable, opts) {
		if (from === undefined) {
		from = require('./internal/streams/from');
		}

		return from(Readable, iterable, opts);
		};
		}

		function indexOf(xs, x) {
		for (var i = 0, l = xs.length; i < l; i++) {
		if (xs[i] === x) return i;
		}

		return -1;
		}
		module.exports = require('./stream').Readable

202

lib/_stream_transform.js

		@@ -1,201 +0,3 @@
		// Copyright Joyent, Inc. and other Node contributors.
		//
		// Permission is hereby granted, free of charge, to any person obtaining a
		// copy of this software and associated documentation files (the
		// "Software"), to deal in the Software without restriction, including
		// without limitation the rights to use, copy, modify, merge, publish,
		// distribute, sublicense, and/or sell copies of the Software, and to permit
		// persons to whom the Software is furnished to do so, subject to the
		// following conditions:
		//
		// The above copyright notice and this permission notice shall be included
		// in all copies or substantial portions of the Software.
		//
		// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
		// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
		// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
		// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
		// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
		// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
		// USE OR OTHER DEALINGS IN THE SOFTWARE.
		// a transform stream is a readable/writable stream where you do
		// something with the data. Sometimes it's called a "filter",
		// but that's not a great name for it, since that implies a thing where
		// some bits pass through, and others are simply ignored. (That would
		// be a valid example of a transform, of course.)
		//
		// While the output is causally related to the input, it's not a
		// necessarily symmetric or synchronous transformation. For example,
		// a zlib stream might take multiple plain-text writes(), and then
		// emit a single compressed chunk some time in the future.
		//
		// Here's how this works:
		//
		// The Transform stream has all the aspects of the readable and writable
		// stream classes. When you write(chunk), that calls _write(chunk,cb)
		// internally, and returns false if there's a lot of pending writes
		// buffered up. When you call read(), that calls _read(n) until
		// there's enough pending readable data buffered up.
		//
		// In a transform stream, the written data is placed in a buffer. When
		// _read(n) is called, it transforms the queued up data, calling the
		// buffered _write cb's as it consumes chunks. If consuming a single
		// written chunk would result in multiple output chunks, then the first
		// outputted bit calls the readcb, and subsequent chunks just go into
		// the read buffer, and will cause it to emit 'readable' if necessary.
		//
		// This way, back-pressure is actually determined by the reading side,
		// since _read has to be called to start processing a new chunk. However,
		// a pathological inflate type of transform can cause excessive buffering
		// here. For example, imagine a stream where every byte of input is
		// interpreted as an integer from 0-255, and then results in that many
		// bytes of output. Writing the 4 bytes {ff,ff,ff,ff} would result in
		// 1kb of data being output. In this case, you could write a very small
		// amount of input, and end up with a very large amount of output. In
		// such a pathological inflating mechanism, there'd be no way to tell
		// the system to stop doing the transform. A single 4MB write could
		// cause the system to run out of memory.
		//
		// However, even in such a pathological case, only a single written chunk
		// would be consumed, and then the rest would wait (un-transformed) until
		// the results of the previous transformed chunk were consumed.
		'use strict';
		'use strict' // Keep this file as an alias for the full stream module.

		module.exports = Transform;

		var _require$codes = require('../errors').codes,
		ERR_METHOD_NOT_IMPLEMENTED = _require$codes.ERR_METHOD_NOT_IMPLEMENTED,
		ERR_MULTIPLE_CALLBACK = _require$codes.ERR_MULTIPLE_CALLBACK,
		ERR_TRANSFORM_ALREADY_TRANSFORMING = _require$codes.ERR_TRANSFORM_ALREADY_TRANSFORMING,
		ERR_TRANSFORM_WITH_LENGTH_0 = _require$codes.ERR_TRANSFORM_WITH_LENGTH_0;

		var Duplex = require('./_stream_duplex');

		require('inherits')(Transform, Duplex);

		function afterTransform(er, data) {
		var ts = this._transformState;
		ts.transforming = false;
		var cb = ts.writecb;

		if (cb === null) {
		return this.emit('error', new ERR_MULTIPLE_CALLBACK());
		}

		ts.writechunk = null;
		ts.writecb = null;
		if (data != null) // single equals check for both `null` and `undefined`
		this.push(data);
		cb(er);
		var rs = this._readableState;
		rs.reading = false;

		if (rs.needReadable \|\| rs.length < rs.highWaterMark) {
		this._read(rs.highWaterMark);
		}
		}

		function Transform(options) {
		if (!(this instanceof Transform)) return new Transform(options);
		Duplex.call(this, options);
		this._transformState = {
		afterTransform: afterTransform.bind(this),
		needTransform: false,
		transforming: false,
		writecb: null,
		writechunk: null,
		writeencoding: null
		}; // start out asking for a readable event once data is transformed.

		this._readableState.needReadable = true; // we have implemented the _read method, and done the other things
		// that Readable wants before the first _read call, so unset the
		// sync guard flag.

		this._readableState.sync = false;

		if (options) {
		if (typeof options.transform === 'function') this._transform = options.transform;
		if (typeof options.flush === 'function') this._flush = options.flush;
		} // When the writable side finishes, then flush out anything remaining.


		this.on('prefinish', prefinish);
		}

		function prefinish() {
		var _this = this;

		if (typeof this._flush === 'function' && !this._readableState.destroyed) {
		this._flush(function (er, data) {
		done(_this, er, data);
		});
		} else {
		done(this, null, null);
		}
		}

		Transform.prototype.push = function (chunk, encoding) {
		this._transformState.needTransform = false;
		return Duplex.prototype.push.call(this, chunk, encoding);
		}; // This is the part where you do stuff!
		// override this function in implementation classes.
		// 'chunk' is an input chunk.
		//
		// Call `push(newChunk)` to pass along transformed output
		// to the readable side. You may call 'push' zero or more times.
		//
		// Call `cb(err)` when you are done with this chunk. If you pass
		// an error, then that'll put the hurt on the whole operation. If you
		// never call cb(), then you'll never get another chunk.


		Transform.prototype._transform = function (chunk, encoding, cb) {
		cb(new ERR_METHOD_NOT_IMPLEMENTED('_transform()'));
		};

		Transform.prototype._write = function (chunk, encoding, cb) {
		var ts = this._transformState;
		ts.writecb = cb;
		ts.writechunk = chunk;
		ts.writeencoding = encoding;

		if (!ts.transforming) {
		var rs = this._readableState;
		if (ts.needTransform \|\| rs.needReadable \|\| rs.length < rs.highWaterMark) this._read(rs.highWaterMark);
		}
		}; // Doesn't matter what the args are here.
		// _transform does all the work.
		// That we got here means that the readable side wants more data.


		Transform.prototype._read = function (n) {
		var ts = this._transformState;

		if (ts.writechunk !== null && !ts.transforming) {
		ts.transforming = true;

		this._transform(ts.writechunk, ts.writeencoding, ts.afterTransform);
		} else {
		// mark that we need a transform, so that any data that comes in
		// will get processed, now that we've asked for it.
		ts.needTransform = true;
		}
		};

		Transform.prototype._destroy = function (err, cb) {
		Duplex.prototype._destroy.call(this, err, function (err2) {
		cb(err2);
		});
		};

		function done(stream, er, data) {
		if (er) return stream.emit('error', er);
		if (data != null) // single equals check for both `null` and `undefined`
		stream.push(data); // TODO(BridgeAR): Write a test for these two error cases
		// if there's nothing in the write buffer, then that means
		// that nothing more will ever be provided

		if (stream._writableState.length) throw new ERR_TRANSFORM_WITH_LENGTH_0();
		if (stream._transformState.transforming) throw new ERR_TRANSFORM_ALREADY_TRANSFORMING();
		return stream.push(null);
		}
		module.exports = require('./stream').Transform

698

lib/_stream_writable.js

		@@ -1,697 +0,3 @@
		// Copyright Joyent, Inc. and other Node contributors.
		//
		// Permission is hereby granted, free of charge, to any person obtaining a
		// copy of this software and associated documentation files (the
		// "Software"), to deal in the Software without restriction, including
		// without limitation the rights to use, copy, modify, merge, publish,
		// distribute, sublicense, and/or sell copies of the Software, and to permit
		// persons to whom the Software is furnished to do so, subject to the
		// following conditions:
		//
		// The above copyright notice and this permission notice shall be included
		// in all copies or substantial portions of the Software.
		//
		// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
		// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
		// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
		// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
		// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
		// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
		// USE OR OTHER DEALINGS IN THE SOFTWARE.
		// A bit simpler than readable streams.
		// Implement an async ._write(chunk, encoding, cb), and it'll handle all
		// the drain event emission and buffering.
		'use strict';
		'use strict' // Keep this file as an alias for the full stream module.

		module.exports = Writable;
		/* <replacement> */

		function WriteReq(chunk, encoding, cb) {
		this.chunk = chunk;
		this.encoding = encoding;
		this.callback = cb;
		this.next = null;
		} // It seems a linked list but it is not
		// there will be only 2 of these for each stream


		function CorkedRequest(state) {
		var _this = this;

		this.next = null;
		this.entry = null;

		this.finish = function () {
		onCorkedFinish(_this, state);
		};
		}
		/* </replacement> */

		/<replacement>/


		var Duplex;
		/</replacement>/

		Writable.WritableState = WritableState;
		/<replacement>/

		var internalUtil = {
		deprecate: require('util-deprecate')
		};
		/</replacement>/

		/<replacement>/

		var Stream = require('./internal/streams/stream');
		/</replacement>/


		var Buffer = require('buffer').Buffer;

		var OurUint8Array = global.Uint8Array \|\| function () {};

		function _uint8ArrayToBuffer(chunk) {
		return Buffer.from(chunk);
		}

		function _isUint8Array(obj) {
		return Buffer.isBuffer(obj) \|\| obj instanceof OurUint8Array;
		}

		var destroyImpl = require('./internal/streams/destroy');

		var _require = require('./internal/streams/state'),
		getHighWaterMark = _require.getHighWaterMark;

		var _require$codes = require('../errors').codes,
		ERR_INVALID_ARG_TYPE = _require$codes.ERR_INVALID_ARG_TYPE,
		ERR_METHOD_NOT_IMPLEMENTED = _require$codes.ERR_METHOD_NOT_IMPLEMENTED,
		ERR_MULTIPLE_CALLBACK = _require$codes.ERR_MULTIPLE_CALLBACK,
		ERR_STREAM_CANNOT_PIPE = _require$codes.ERR_STREAM_CANNOT_PIPE,
		ERR_STREAM_DESTROYED = _require$codes.ERR_STREAM_DESTROYED,
		ERR_STREAM_NULL_VALUES = _require$codes.ERR_STREAM_NULL_VALUES,
		ERR_STREAM_WRITE_AFTER_END = _require$codes.ERR_STREAM_WRITE_AFTER_END,
		ERR_UNKNOWN_ENCODING = _require$codes.ERR_UNKNOWN_ENCODING;

		var errorOrDestroy = destroyImpl.errorOrDestroy;

		require('inherits')(Writable, Stream);

		function nop() {}

		function WritableState(options, stream, isDuplex) {
		Duplex = Duplex \|\| require('./_stream_duplex');
		options = options \|\| {}; // Duplex streams are both readable and writable, but share
		// the same options object.
		// However, some cases require setting options to different
		// values for the readable and the writable sides of the duplex stream,
		// e.g. options.readableObjectMode vs. options.writableObjectMode, etc.

		if (typeof isDuplex !== 'boolean') isDuplex = stream instanceof Duplex; // object stream flag to indicate whether or not this stream
		// contains buffers or objects.

		this.objectMode = !!options.objectMode;
		if (isDuplex) this.objectMode = this.objectMode \|\| !!options.writableObjectMode; // the point at which write() starts returning false
		// Note: 0 is a valid value, means that we always return false if
		// the entire buffer is not flushed immediately on write()

		this.highWaterMark = getHighWaterMark(this, options, 'writableHighWaterMark', isDuplex); // if _final has been called

		this.finalCalled = false; // drain event flag.

		this.needDrain = false; // at the start of calling end()

		this.ending = false; // when end() has been called, and returned

		this.ended = false; // when 'finish' is emitted

		this.finished = false; // has it been destroyed

		this.destroyed = false; // should we decode strings into buffers before passing to _write?
		// this is here so that some node-core streams can optimize string
		// handling at a lower level.

		var noDecode = options.decodeStrings === false;
		this.decodeStrings = !noDecode; // Crypto is kind of old and crusty. Historically, its default string
		// encoding is 'binary' so we have to make this configurable.
		// Everything else in the universe uses 'utf8', though.

		this.defaultEncoding = options.defaultEncoding \|\| 'utf8'; // not an actual buffer we keep track of, but a measurement
		// of how much we're waiting to get pushed to some underlying
		// socket or file.

		this.length = 0; // a flag to see when we're in the middle of a write.

		this.writing = false; // when true all writes will be buffered until .uncork() call

		this.corked = 0; // a flag to be able to tell if the onwrite cb is called immediately,
		// or on a later tick. We set this to true at first, because any
		// actions that shouldn't happen until "later" should generally also
		// not happen before the first write call.

		this.sync = true; // a flag to know if we're processing previously buffered items, which
		// may call the _write() callback in the same tick, so that we don't
		// end up in an overlapped onwrite situation.

		this.bufferProcessing = false; // the callback that's passed to _write(chunk,cb)

		this.onwrite = function (er) {
		onwrite(stream, er);
		}; // the callback that the user supplies to write(chunk,encoding,cb)


		this.writecb = null; // the amount that is being written when _write is called.

		this.writelen = 0;
		this.bufferedRequest = null;
		this.lastBufferedRequest = null; // number of pending user-supplied write callbacks
		// this must be 0 before 'finish' can be emitted

		this.pendingcb = 0; // emit prefinish if the only thing we're waiting for is _write cbs
		// This is relevant for synchronous Transform streams

		this.prefinished = false; // True if the error was already emitted and should not be thrown again

		this.errorEmitted = false; // Should close be emitted on destroy. Defaults to true.

		this.emitClose = options.emitClose !== false; // Should .destroy() be called after 'finish' (and potentially 'end')

		this.autoDestroy = !!options.autoDestroy; // count buffered requests

		this.bufferedRequestCount = 0; // allocate the first CorkedRequest, there is always
		// one allocated and free to use, and we maintain at most two

		this.corkedRequestsFree = new CorkedRequest(this);
		}

		WritableState.prototype.getBuffer = function getBuffer() {
		var current = this.bufferedRequest;
		var out = [];

		while (current) {
		out.push(current);
		current = current.next;
		}

		return out;
		};

		(function () {
		try {
		Object.defineProperty(WritableState.prototype, 'buffer', {
		get: internalUtil.deprecate(function writableStateBufferGetter() {
		return this.getBuffer();
		}, '_writableState.buffer is deprecated. Use _writableState.getBuffer ' + 'instead.', 'DEP0003')
		});
		} catch (_) {}
		})(); // Test _writableState for inheritance to account for Duplex streams,
		// whose prototype chain only points to Readable.


		var realHasInstance;

		if (typeof Symbol === 'function' && Symbol.hasInstance && typeof Function.prototype[Symbol.hasInstance] === 'function') {
		realHasInstance = Function.prototype[Symbol.hasInstance];
		Object.defineProperty(Writable, Symbol.hasInstance, {
		value: function value(object) {
		if (realHasInstance.call(this, object)) return true;
		if (this !== Writable) return false;
		return object && object._writableState instanceof WritableState;
		}
		});
		} else {
		realHasInstance = function realHasInstance(object) {
		return object instanceof this;
		};
		}

		function Writable(options) {
		Duplex = Duplex \|\| require('./_stream_duplex'); // Writable ctor is applied to Duplexes, too.
		// `realHasInstance` is necessary because using plain `instanceof`
		// would return false, as no `_writableState` property is attached.
		// Trying to use the custom `instanceof` for Writable here will also break the
		// Node.js LazyTransform implementation, which has a non-trivial getter for
		// `_writableState` that would lead to infinite recursion.
		// Checking for a Stream.Duplex instance is faster here instead of inside
		// the WritableState constructor, at least with V8 6.5

		var isDuplex = this instanceof Duplex;
		if (!isDuplex && !realHasInstance.call(Writable, this)) return new Writable(options);
		this._writableState = new WritableState(options, this, isDuplex); // legacy.

		this.writable = true;

		if (options) {
		if (typeof options.write === 'function') this._write = options.write;
		if (typeof options.writev === 'function') this._writev = options.writev;
		if (typeof options.destroy === 'function') this._destroy = options.destroy;
		if (typeof options.final === 'function') this._final = options.final;
		}

		Stream.call(this);
		} // Otherwise people can pipe Writable streams, which is just wrong.


		Writable.prototype.pipe = function () {
		errorOrDestroy(this, new ERR_STREAM_CANNOT_PIPE());
		};

		function writeAfterEnd(stream, cb) {
		var er = new ERR_STREAM_WRITE_AFTER_END(); // TODO: defer error events consistently everywhere, not just the cb

		errorOrDestroy(stream, er);
		process.nextTick(cb, er);
		} // Checks that a user-supplied chunk is valid, especially for the particular
		// mode the stream is in. Currently this means that `null` is never accepted
		// and undefined/non-string values are only allowed in object mode.


		function validChunk(stream, state, chunk, cb) {
		var er;

		if (chunk === null) {
		er = new ERR_STREAM_NULL_VALUES();
		} else if (typeof chunk !== 'string' && !state.objectMode) {
		er = new ERR_INVALID_ARG_TYPE('chunk', ['string', 'Buffer'], chunk);
		}

		if (er) {
		errorOrDestroy(stream, er);
		process.nextTick(cb, er);
		return false;
		}

		return true;
		}

		Writable.prototype.write = function (chunk, encoding, cb) {
		var state = this._writableState;
		var ret = false;

		var isBuf = !state.objectMode && _isUint8Array(chunk);

		if (isBuf && !Buffer.isBuffer(chunk)) {
		chunk = _uint8ArrayToBuffer(chunk);
		}

		if (typeof encoding === 'function') {
		cb = encoding;
		encoding = null;
		}

		if (isBuf) encoding = 'buffer';else if (!encoding) encoding = state.defaultEncoding;
		if (typeof cb !== 'function') cb = nop;
		if (state.ending) writeAfterEnd(this, cb);else if (isBuf \|\| validChunk(this, state, chunk, cb)) {
		state.pendingcb++;
		ret = writeOrBuffer(this, state, isBuf, chunk, encoding, cb);
		}
		return ret;
		};

		Writable.prototype.cork = function () {
		this._writableState.corked++;
		};

		Writable.prototype.uncork = function () {
		var state = this._writableState;

		if (state.corked) {
		state.corked--;
		if (!state.writing && !state.corked && !state.bufferProcessing && state.bufferedRequest) clearBuffer(this, state);
		}
		};

		Writable.prototype.setDefaultEncoding = function setDefaultEncoding(encoding) {
		// node::ParseEncoding() requires lower case.
		if (typeof encoding === 'string') encoding = encoding.toLowerCase();
		if (!(['hex', 'utf8', 'utf-8', 'ascii', 'binary', 'base64', 'ucs2', 'ucs-2', 'utf16le', 'utf-16le', 'raw'].indexOf((encoding + '').toLowerCase()) > -1)) throw new ERR_UNKNOWN_ENCODING(encoding);
		this._writableState.defaultEncoding = encoding;
		return this;
		};

		Object.defineProperty(Writable.prototype, 'writableBuffer', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._writableState && this._writableState.getBuffer();
		}
		});

		function decodeChunk(state, chunk, encoding) {
		if (!state.objectMode && state.decodeStrings !== false && typeof chunk === 'string') {
		chunk = Buffer.from(chunk, encoding);
		}

		return chunk;
		}

		Object.defineProperty(Writable.prototype, 'writableHighWaterMark', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._writableState.highWaterMark;
		}
		}); // if we're already writing something, then just put this
		// in the queue, and wait our turn. Otherwise, call _write
		// If we return false, then we need a drain event, so set that flag.

		function writeOrBuffer(stream, state, isBuf, chunk, encoding, cb) {
		if (!isBuf) {
		var newChunk = decodeChunk(state, chunk, encoding);

		if (chunk !== newChunk) {
		isBuf = true;
		encoding = 'buffer';
		chunk = newChunk;
		}
		}

		var len = state.objectMode ? 1 : chunk.length;
		state.length += len;
		var ret = state.length < state.highWaterMark; // we must ensure that previous needDrain will not be reset to false.

		if (!ret) state.needDrain = true;

		if (state.writing \|\| state.corked) {
		var last = state.lastBufferedRequest;
		state.lastBufferedRequest = {
		chunk: chunk,
		encoding: encoding,
		isBuf: isBuf,
		callback: cb,
		next: null
		};

		if (last) {
		last.next = state.lastBufferedRequest;
		} else {
		state.bufferedRequest = state.lastBufferedRequest;
		}

		state.bufferedRequestCount += 1;
		} else {
		doWrite(stream, state, false, len, chunk, encoding, cb);
		}

		return ret;
		}

		function doWrite(stream, state, writev, len, chunk, encoding, cb) {
		state.writelen = len;
		state.writecb = cb;
		state.writing = true;
		state.sync = true;
		if (state.destroyed) state.onwrite(new ERR_STREAM_DESTROYED('write'));else if (writev) stream._writev(chunk, state.onwrite);else stream._write(chunk, encoding, state.onwrite);
		state.sync = false;
		}

		function onwriteError(stream, state, sync, er, cb) {
		--state.pendingcb;

		if (sync) {
		// defer the callback if we are being called synchronously
		// to avoid piling up things on the stack
		process.nextTick(cb, er); // this can emit finish, and it will always happen
		// after error

		process.nextTick(finishMaybe, stream, state);
		stream._writableState.errorEmitted = true;
		errorOrDestroy(stream, er);
		} else {
		// the caller expect this to happen before if
		// it is async
		cb(er);
		stream._writableState.errorEmitted = true;
		errorOrDestroy(stream, er); // this can emit finish, but finish must
		// always follow error

		finishMaybe(stream, state);
		}
		}

		function onwriteStateUpdate(state) {
		state.writing = false;
		state.writecb = null;
		state.length -= state.writelen;
		state.writelen = 0;
		}

		function onwrite(stream, er) {
		var state = stream._writableState;
		var sync = state.sync;
		var cb = state.writecb;
		if (typeof cb !== 'function') throw new ERR_MULTIPLE_CALLBACK();
		onwriteStateUpdate(state);
		if (er) onwriteError(stream, state, sync, er, cb);else {
		// Check if we're actually ready to finish, but don't emit yet
		var finished = needFinish(state) \|\| stream.destroyed;

		if (!finished && !state.corked && !state.bufferProcessing && state.bufferedRequest) {
		clearBuffer(stream, state);
		}

		if (sync) {
		process.nextTick(afterWrite, stream, state, finished, cb);
		} else {
		afterWrite(stream, state, finished, cb);
		}
		}
		}

		function afterWrite(stream, state, finished, cb) {
		if (!finished) onwriteDrain(stream, state);
		state.pendingcb--;
		cb();
		finishMaybe(stream, state);
		} // Must force callback to be called on nextTick, so that we don't
		// emit 'drain' before the write() consumer gets the 'false' return
		// value, and has a chance to attach a 'drain' listener.


		function onwriteDrain(stream, state) {
		if (state.length === 0 && state.needDrain) {
		state.needDrain = false;
		stream.emit('drain');
		}
		} // if there's something in the buffer waiting, then process it


		function clearBuffer(stream, state) {
		state.bufferProcessing = true;
		var entry = state.bufferedRequest;

		if (stream._writev && entry && entry.next) {
		// Fast case, write everything using _writev()
		var l = state.bufferedRequestCount;
		var buffer = new Array(l);
		var holder = state.corkedRequestsFree;
		holder.entry = entry;
		var count = 0;
		var allBuffers = true;

		while (entry) {
		buffer[count] = entry;
		if (!entry.isBuf) allBuffers = false;
		entry = entry.next;
		count += 1;
		}

		buffer.allBuffers = allBuffers;
		doWrite(stream, state, true, state.length, buffer, '', holder.finish); // doWrite is almost always async, defer these to save a bit of time
		// as the hot path ends with doWrite

		state.pendingcb++;
		state.lastBufferedRequest = null;

		if (holder.next) {
		state.corkedRequestsFree = holder.next;
		holder.next = null;
		} else {
		state.corkedRequestsFree = new CorkedRequest(state);
		}

		state.bufferedRequestCount = 0;
		} else {
		// Slow case, write chunks one-by-one
		while (entry) {
		var chunk = entry.chunk;
		var encoding = entry.encoding;
		var cb = entry.callback;
		var len = state.objectMode ? 1 : chunk.length;
		doWrite(stream, state, false, len, chunk, encoding, cb);
		entry = entry.next;
		state.bufferedRequestCount--; // if we didn't call the onwrite immediately, then
		// it means that we need to wait until it does.
		// also, that means that the chunk and cb are currently
		// being processed, so move the buffer counter past them.

		if (state.writing) {
		break;
		}
		}

		if (entry === null) state.lastBufferedRequest = null;
		}

		state.bufferedRequest = entry;
		state.bufferProcessing = false;
		}

		Writable.prototype._write = function (chunk, encoding, cb) {
		cb(new ERR_METHOD_NOT_IMPLEMENTED('_write()'));
		};

		Writable.prototype._writev = null;

		Writable.prototype.end = function (chunk, encoding, cb) {
		var state = this._writableState;

		if (typeof chunk === 'function') {
		cb = chunk;
		chunk = null;
		encoding = null;
		} else if (typeof encoding === 'function') {
		cb = encoding;
		encoding = null;
		}

		if (chunk !== null && chunk !== undefined) this.write(chunk, encoding); // .end() fully uncorks

		if (state.corked) {
		state.corked = 1;
		this.uncork();
		} // ignore unnecessary end() calls.


		if (!state.ending) endWritable(this, state, cb);
		return this;
		};

		Object.defineProperty(Writable.prototype, 'writableLength', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		return this._writableState.length;
		}
		});

		function needFinish(state) {
		return state.ending && state.length === 0 && state.bufferedRequest === null && !state.finished && !state.writing;
		}

		function callFinal(stream, state) {
		stream._final(function (err) {
		state.pendingcb--;

		if (err) {
		errorOrDestroy(stream, err);
		}

		state.prefinished = true;
		stream.emit('prefinish');
		finishMaybe(stream, state);
		});
		}

		function prefinish(stream, state) {
		if (!state.prefinished && !state.finalCalled) {
		if (typeof stream._final === 'function' && !state.destroyed) {
		state.pendingcb++;
		state.finalCalled = true;
		process.nextTick(callFinal, stream, state);
		} else {
		state.prefinished = true;
		stream.emit('prefinish');
		}
		}
		}

		function finishMaybe(stream, state) {
		var need = needFinish(state);

		if (need) {
		prefinish(stream, state);

		if (state.pendingcb === 0) {
		state.finished = true;
		stream.emit('finish');

		if (state.autoDestroy) {
		// In case of duplex streams we need a way to detect
		// if the readable side is ready for autoDestroy as well
		var rState = stream._readableState;

		if (!rState \|\| rState.autoDestroy && rState.endEmitted) {
		stream.destroy();
		}
		}
		}
		}

		return need;
		}

		function endWritable(stream, state, cb) {
		state.ending = true;
		finishMaybe(stream, state);

		if (cb) {
		if (state.finished) process.nextTick(cb);else stream.once('finish', cb);
		}

		state.ended = true;
		stream.writable = false;
		}

		function onCorkedFinish(corkReq, state, err) {
		var entry = corkReq.entry;
		corkReq.entry = null;

		while (entry) {
		var cb = entry.callback;
		state.pendingcb--;
		cb(err);
		entry = entry.next;
		} // reuse the free corkReq.


		state.corkedRequestsFree.next = corkReq;
		}

		Object.defineProperty(Writable.prototype, 'destroyed', {
		// making it explicit this property is not enumerable
		// because otherwise some prototype manipulation in
		// userland will fail
		enumerable: false,
		get: function get() {
		if (this._writableState === undefined) {
		return false;
		}

		return this._writableState.destroyed;
		},
		set: function set(value) {
		// we ignore the value if the stream
		// has not been initialized yet
		if (!this._writableState) {
		return;
		} // backward compatibility, the user is explicitly
		// managing destroyed


		this._writableState.destroyed = value;
		}
		});
		Writable.prototype.destroy = destroyImpl.destroy;
		Writable.prototype._undestroy = destroyImpl.undestroy;

		Writable.prototype._destroy = function (err, cb) {
		cb(err);
		};
		module.exports = require('./stream').Writable

312

lib/internal/streams/buffer_list.js

		@@ -1,210 +0,178 @@
		'use strict';
		'use strict'

		function ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); if (enumerableOnly) symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; }); keys.push.apply(keys, symbols); } return keys; }
		const { StringPrototypeSlice, SymbolIterator, TypedArrayPrototypeSet, Uint8Array } = require('../../ours/primordials')

		function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; if (i % 2) { ownKeys(Object(source), true).forEach(function (key) { _defineProperty(target, key, source[key]); }); } else if (Object.getOwnPropertyDescriptors) { Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); } else { ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } } return target; }
		const { inspect } = require('../../ours/util')

		function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }
		module.exports = class BufferList {
		constructor() {
		this.head = null
		this.tail = null
		this.length = 0
		}

		function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
		push(v) {
		const entry = {
		data: v,
		next: null
		}
		if (this.length > 0) this.tail.next = entry
		else this.head = entry
		this.tail = entry
		++this.length
		}

		function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable \|\| false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }
		unshift(v) {
		const entry = {
		data: v,
		next: this.head
		}
		if (this.length === 0) this.tail = entry
		this.head = entry
		++this.length
		}

		function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }
		shift() {
		if (this.length === 0) return
		const ret = this.head.data
		if (this.length === 1) this.head = this.tail = null
		else this.head = this.head.next
		--this.length
		return ret
		}

		var _require = require('buffer'),
		Buffer = _require.Buffer;
		clear() {
		this.head = this.tail = null
		this.length = 0
		}

		var _require2 = require('util'),
		inspect = _require2.inspect;
		join(s) {
		if (this.length === 0) return ''
		let p = this.head
		let ret = '' + p.data

		var custom = inspect && inspect.custom \|\| 'inspect';
		while ((p = p.next) !== null) ret += s + p.data

		function copyBuffer(src, target, offset) {
		Buffer.prototype.copy.call(src, target, offset);
		}
		return ret
		}

		module.exports =
		/#__PURE__/
		function () {
		function BufferList() {
		_classCallCheck(this, BufferList);
		concat(n) {
		if (this.length === 0) return Buffer.alloc(0)
		const ret = Buffer.allocUnsafe(n >>> 0)
		let p = this.head
		let i = 0

		this.head = null;
		this.tail = null;
		this.length = 0;
		}

		_createClass(BufferList, [{
		key: "push",
		value: function push(v) {
		var entry = {
		data: v,
		next: null
		};
		if (this.length > 0) this.tail.next = entry;else this.head = entry;
		this.tail = entry;
		++this.length;
		while (p) {
		TypedArrayPrototypeSet(ret, p.data, i)
		i += p.data.length
		p = p.next
		}
		}, {
		key: "unshift",
		value: function unshift(v) {
		var entry = {
		data: v,
		next: this.head
		};
		if (this.length === 0) this.tail = entry;
		this.head = entry;
		++this.length;
		}
		}, {
		key: "shift",
		value: function shift() {
		if (this.length === 0) return;
		var ret = this.head.data;
		if (this.length === 1) this.head = this.tail = null;else this.head = this.head.next;
		--this.length;
		return ret;
		}
		}, {
		key: "clear",
		value: function clear() {
		this.head = this.tail = null;
		this.length = 0;
		}
		}, {
		key: "join",
		value: function join(s) {
		if (this.length === 0) return '';
		var p = this.head;
		var ret = '' + p.data;

		while (p = p.next) {
		ret += s + p.data;
		}
		return ret
		} // Consumes a specified amount of bytes or characters from the buffered data.

		return ret;
		consume(n, hasStrings) {
		const data = this.head.data

		if (n < data.length) {
		// `slice` is the same for buffers and strings.
		const slice = data.slice(0, n)
		this.head.data = data.slice(n)
		return slice
		}
		}, {
		key: "concat",
		value: function concat(n) {
		if (this.length === 0) return Buffer.alloc(0);
		var ret = Buffer.allocUnsafe(n >>> 0);
		var p = this.head;
		var i = 0;

		while (p) {
		copyBuffer(p.data, ret, i);
		i += p.data.length;
		p = p.next;
		}
		if (n === data.length) {
		// First chunk is a perfect match.
		return this.shift()
		} // Result spans more than one buffer.

		return ret;
		} // Consumes a specified amount of bytes or characters from the buffered data.
		return hasStrings ? this._getString(n) : this._getBuffer(n)
		}

		}, {
		key: "consume",
		value: function consume(n, hasStrings) {
		var ret;
		first() {
		return this.head.data
		}

		if (n < this.head.data.length) {
		// `slice` is the same for buffers and strings.
		ret = this.head.data.slice(0, n);
		this.head.data = this.head.data.slice(n);
		} else if (n === this.head.data.length) {
		// First chunk is a perfect match.
		ret = this.shift();
		} else {
		// Result spans more than one buffer.
		ret = hasStrings ? this._getString(n) : this._getBuffer(n);
		}

		return ret;
		*[SymbolIterator]() {
		for (let p = this.head; p; p = p.next) {
		yield p.data
		}
		}, {
		key: "first",
		value: function first() {
		return this.head.data;
		} // Consumes a specified amount of characters from the buffered data.
		} // Consumes a specified amount of characters from the buffered data.

		}, {
		key: "_getString",
		value: function _getString(n) {
		var p = this.head;
		var c = 1;
		var ret = p.data;
		n -= ret.length;
		_getString(n) {
		let ret = ''
		let p = this.head
		let c = 0

		while (p = p.next) {
		var str = p.data;
		var nb = n > str.length ? str.length : n;
		if (nb === str.length) ret += str;else ret += str.slice(0, n);
		n -= nb;
		do {
		const str = p.data

		if (n === 0) {
		if (nb === str.length) {
		++c;
		if (p.next) this.head = p.next;else this.head = this.tail = null;
		} else {
		this.head = p;
		p.data = str.slice(nb);
		}

		break;
		if (n > str.length) {
		ret += str
		n -= str.length
		} else {
		if (n === str.length) {
		ret += str
		++c
		if (p.next) this.head = p.next
		else this.head = this.tail = null
		} else {
		ret += StringPrototypeSlice(str, 0, n)
		this.head = p
		p.data = StringPrototypeSlice(str, n)
		}

		++c;
		break
		}

		this.length -= c;
		return ret;
		} // Consumes a specified amount of bytes from the buffered data.
		++c
		} while ((p = p.next) !== null)

		}, {
		key: "_getBuffer",
		value: function _getBuffer(n) {
		var ret = Buffer.allocUnsafe(n);
		var p = this.head;
		var c = 1;
		p.data.copy(ret);
		n -= p.data.length;
		this.length -= c
		return ret
		} // Consumes a specified amount of bytes from the buffered data.

		while (p = p.next) {
		var buf = p.data;
		var nb = n > buf.length ? buf.length : n;
		buf.copy(ret, ret.length - n, 0, nb);
		n -= nb;
		_getBuffer(n) {
		const ret = Buffer.allocUnsafe(n)
		const retLen = n
		let p = this.head
		let c = 0

		if (n === 0) {
		if (nb === buf.length) {
		++c;
		if (p.next) this.head = p.next;else this.head = this.tail = null;
		} else {
		this.head = p;
		p.data = buf.slice(nb);
		}
		do {
		const buf = p.data

		break;
		if (n > buf.length) {
		TypedArrayPrototypeSet(ret, buf, retLen - n)
		n -= buf.length
		} else {
		if (n === buf.length) {
		TypedArrayPrototypeSet(ret, buf, retLen - n)
		++c
		if (p.next) this.head = p.next
		else this.head = this.tail = null
		} else {
		TypedArrayPrototypeSet(ret, new Uint8Array(buf.buffer, buf.byteOffset, n), retLen - n)
		this.head = p
		p.data = buf.slice(n)
		}

		++c;
		break
		}

		this.length -= c;
		return ret;
		} // Make sure the linked list only shows the minimal necessary information.
		++c
		} while ((p = p.next) !== null)

		}, {
		key: custom,
		value: function value(_, options) {
		return inspect(this, _objectSpread({}, options, {
		// Only inspect one level.
		depth: 0,
		// It should not recurse.
		customInspect: false
		}));
		}
		}]);
		this.length -= c
		return ret
		} // Make sure the linked list only shows the minimal necessary information.

		return BufferList;
		}();
		[Symbol.for('nodejs.util.inspect.custom')](_, options) {
		return inspect(this, {
		...options,
		// Only inspect one level.
		depth: 0,
		// It should not recurse.
		customInspect: false
		})
		}
		}

361

lib/internal/streams/destroy.js

		@@ -1,91 +0,180 @@
		'use strict'; // undocumented cb() API, needed for core, not for public API
		'use strict'

		const {
		aggregateTwoErrors,
		codes: { ERR_MULTIPLE_CALLBACK },
		AbortError
		} = require('../../ours/errors')

		const { Symbol } = require('../../ours/primordials')

		const { kDestroyed, isDestroyed, isFinished, isServerRequest } = require('./utils')

		const kDestroy = Symbol('kDestroy')
		const kConstruct = Symbol('kConstruct')

		function checkError(err, w, r) {
		if (err) {
		// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
		err.stack // eslint-disable-line no-unused-expressions

		if (w && !w.errored) {
		w.errored = err
		}

		if (r && !r.errored) {
		r.errored = err
		}
		}
		} // Backwards compat. cb() is undocumented and unused in core but
		// unfortunately might be used by modules.

		function destroy(err, cb) {
		var _this = this;
		const r = this._readableState
		const w = this._writableState // With duplex streams we use the writable side for state.

		var readableDestroyed = this._readableState && this._readableState.destroyed;
		var writableDestroyed = this._writableState && this._writableState.destroyed;
		const s = w \|\| r

		if (readableDestroyed \|\| writableDestroyed) {
		if (cb) {
		cb(err);
		} else if (err) {
		if (!this._writableState) {
		process.nextTick(emitErrorNT, this, err);
		} else if (!this._writableState.errorEmitted) {
		this._writableState.errorEmitted = true;
		process.nextTick(emitErrorNT, this, err);
		}
		if ((w && w.destroyed) \|\| (r && r.destroyed)) {
		if (typeof cb === 'function') {
		cb()
		}

		return this;
		} // we set destroyed to true before firing error callbacks in order
		return this
		} // We set destroyed to true before firing error callbacks in order
		// to make it re-entrance safe in case destroy() is called within callbacks

		checkError(err, w, r)

		if (this._readableState) {
		this._readableState.destroyed = true;
		} // if this is a duplex stream mark the writable part as destroyed as well
		if (w) {
		w.destroyed = true
		}

		if (r) {
		r.destroyed = true
		} // If still constructing then defer calling _destroy.

		if (this._writableState) {
		this._writableState.destroyed = true;
		if (!s.constructed) {
		this.once(kDestroy, function (er) {
		_destroy(this, aggregateTwoErrors(er, err), cb)
		})
		} else {
		_destroy(this, err, cb)
		}

		this._destroy(err \|\| null, function (err) {
		if (!cb && err) {
		if (!_this._writableState) {
		process.nextTick(emitErrorAndCloseNT, _this, err);
		} else if (!_this._writableState.errorEmitted) {
		_this._writableState.errorEmitted = true;
		process.nextTick(emitErrorAndCloseNT, _this, err);
		} else {
		process.nextTick(emitCloseNT, _this);
		}
		} else if (cb) {
		process.nextTick(emitCloseNT, _this);
		cb(err);
		return this
		}

		function _destroy(self, err, cb) {
		let called = false

		function onDestroy(err) {
		if (called) {
		return
		}

		called = true
		const r = self._readableState
		const w = self._writableState
		checkError(err, w, r)

		if (w) {
		w.closed = true
		}

		if (r) {
		r.closed = true
		}

		if (typeof cb === 'function') {
		cb(err)
		}

		if (err) {
		process.nextTick(emitErrorCloseNT, self, err)
		} else {
		process.nextTick(emitCloseNT, _this);
		process.nextTick(emitCloseNT, self)
		}
		});
		}

		return this;
		try {
		self._destroy(err \|\| null, onDestroy)
		} catch (err) {
		onDestroy(err)
		}
		}

		function emitErrorAndCloseNT(self, err) {
		emitErrorNT(self, err);
		emitCloseNT(self);
		function emitErrorCloseNT(self, err) {
		emitErrorNT(self, err)
		emitCloseNT(self)
		}

		function emitCloseNT(self) {
		if (self._writableState && !self._writableState.emitClose) return;
		if (self._readableState && !self._readableState.emitClose) return;
		self.emit('close');
		}
		const r = self._readableState
		const w = self._writableState

		function undestroy() {
		if (this._readableState) {
		this._readableState.destroyed = false;
		this._readableState.reading = false;
		this._readableState.ended = false;
		this._readableState.endEmitted = false;
		if (w) {
		w.closeEmitted = true
		}

		if (this._writableState) {
		this._writableState.destroyed = false;
		this._writableState.ended = false;
		this._writableState.ending = false;
		this._writableState.finalCalled = false;
		this._writableState.prefinished = false;
		this._writableState.finished = false;
		this._writableState.errorEmitted = false;
		if (r) {
		r.closeEmitted = true
		}

		if ((w && w.emitClose) \|\| (r && r.emitClose)) {
		self.emit('close')
		}
		}

		function emitErrorNT(self, err) {
		self.emit('error', err);
		const r = self._readableState
		const w = self._writableState

		if ((w && w.errorEmitted) \|\| (r && r.errorEmitted)) {
		return
		}

		if (w) {
		w.errorEmitted = true
		}

		if (r) {
		r.errorEmitted = true
		}

		self.emit('error', err)
		}

		function errorOrDestroy(stream, err) {
		function undestroy() {
		const r = this._readableState
		const w = this._writableState

		if (r) {
		r.constructed = true
		r.closed = false
		r.closeEmitted = false
		r.destroyed = false
		r.errored = null
		r.errorEmitted = false
		r.reading = false
		r.ended = r.readable === false
		r.endEmitted = r.readable === false
		}

		if (w) {
		w.constructed = true
		w.destroyed = false
		w.closed = false
		w.closeEmitted = false
		w.errored = null
		w.errorEmitted = false
		w.finalCalled = false
		w.prefinished = false
		w.ended = w.writable === false
		w.ending = w.writable === false
		w.finished = w.writable === false
		}
		}

		function errorOrDestroy(stream, err, sync) {
		// We have tests that rely on errors being emitted
		@@ -96,11 +185,149 @@ // in the same tick, so changing this is semver major.
		// semver major update we should change the default to this.
		var rState = stream._readableState;
		var wState = stream._writableState;
		if (rState && rState.autoDestroy \|\| wState && wState.autoDestroy) stream.destroy(err);else stream.emit('error', err);
		const r = stream._readableState
		const w = stream._writableState

		if ((w && w.destroyed) \|\| (r && r.destroyed)) {
		return this
		}

		if ((r && r.autoDestroy) \|\| (w && w.autoDestroy)) stream.destroy(err)
		else if (err) {
		// Avoid V8 leak, https://github.com/nodejs/node/pull/34103#issuecomment-652002364
		err.stack // eslint-disable-line no-unused-expressions

		if (w && !w.errored) {
		w.errored = err
		}

		if (r && !r.errored) {
		r.errored = err
		}

		if (sync) {
		process.nextTick(emitErrorNT, stream, err)
		} else {
		emitErrorNT(stream, err)
		}
		}
		}

		function construct(stream, cb) {
		if (typeof stream._construct !== 'function') {
		return
		}

		const r = stream._readableState
		const w = stream._writableState

		if (r) {
		r.constructed = false
		}

		if (w) {
		w.constructed = false
		}

		stream.once(kConstruct, cb)

		if (stream.listenerCount(kConstruct) > 1) {
		// Duplex
		return
		}

		process.nextTick(constructNT, stream)
		}

		function constructNT(stream) {
		let called = false

		function onConstruct(err) {
		if (called) {
		errorOrDestroy(stream, err !== null && err !== undefined ? err : new ERR_MULTIPLE_CALLBACK())
		return
		}

		called = true
		const r = stream._readableState
		const w = stream._writableState
		const s = w \|\| r

		if (r) {
		r.constructed = true
		}

		if (w) {
		w.constructed = true
		}

		if (s.destroyed) {
		stream.emit(kDestroy, err)
		} else if (err) {
		errorOrDestroy(stream, err, true)
		} else {
		process.nextTick(emitConstructNT, stream)
		}
		}

		try {
		stream._construct(onConstruct)
		} catch (err) {
		onConstruct(err)
		}
		}

		function emitConstructNT(stream) {
		stream.emit(kConstruct)
		}

		function isRequest(stream) {
		return stream && stream.setHeader && typeof stream.abort === 'function'
		}

		function emitCloseLegacy(stream) {
		stream.emit('close')
		}

		function emitErrorCloseLegacy(stream, err) {
		stream.emit('error', err)
		process.nextTick(emitCloseLegacy, stream)
		} // Normalize destroy for legacy.

		function destroyer(stream, err) {
		if (!stream \|\| isDestroyed(stream)) {
		return
		}

		if (!err && !isFinished(stream)) {
		err = new AbortError()
		} // TODO: Remove isRequest branches.

		if (isServerRequest(stream)) {
		stream.socket = null
		stream.destroy(err)
		} else if (isRequest(stream)) {
		stream.abort()
		} else if (isRequest(stream.req)) {
		stream.req.abort()
		} else if (typeof stream.destroy === 'function') {
		stream.destroy(err)
		} else if (typeof stream.close === 'function') {
		// TODO: Don't lose err?
		stream.close()
		} else if (err) {
		process.nextTick(emitErrorCloseLegacy, stream)
		} else {
		process.nextTick(emitCloseLegacy, stream)
		}

		if (!stream.destroyed) {
		stream[kDestroyed] = true
		}
		}

		module.exports = {
		destroy: destroy,
		undestroy: undestroy,
		errorOrDestroy: errorOrDestroy
		};
		construct,
		destroyer,
		destroy,
		undestroy,
		errorOrDestroy
		}

302

lib/internal/streams/end-of-stream.js

		// Ported from https://github.com/mafintosh/end-of-stream with
		// permission from the author, Mathias Buus (@mafintosh).
		'use strict';
		'use strict'

		var ERR_STREAM_PREMATURE_CLOSE = require('../../../errors').codes.ERR_STREAM_PREMATURE_CLOSE;
		const { AbortError, codes } = require('../../ours/errors')

		function once(callback) {
		var called = false;
		return function () {
		if (called) return;
		called = true;
		const { ERR_INVALID_ARG_TYPE, ERR_STREAM_PREMATURE_CLOSE } = codes

		for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
		args[_key] = arguments[_key];
		}
		const { once } = require('../../ours/util')

		callback.apply(this, args);
		};
		}
		const { validateAbortSignal, validateFunction, validateObject } = require('../validators')

		function noop() {}
		const { Promise } = require('../../ours/primordials')

		const {
		isClosed,
		isReadable,
		isReadableNodeStream,
		isReadableFinished,
		isReadableErrored,
		isWritable,
		isWritableNodeStream,
		isWritableFinished,
		isWritableErrored,
		isNodeStream,
		willEmitClose: _willEmitClose
		} = require('./utils')

		function isRequest(stream) {
		return stream.setHeader && typeof stream.abort === 'function';
		return stream.setHeader && typeof stream.abort === 'function'
		}

		function eos(stream, opts, callback) {
		if (typeof opts === 'function') return eos(stream, null, opts);
		if (!opts) opts = {};
		callback = once(callback \|\| noop);
		var readable = opts.readable \|\| opts.readable !== false && stream.readable;
		var writable = opts.writable \|\| opts.writable !== false && stream.writable;
		const nop = () => {}

		var onlegacyfinish = function onlegacyfinish() {
		if (!stream.writable) onfinish();
		};
		function eos(stream, options, callback) {
		var _options$readable, _options$writable

		var writableEnded = stream._writableState && stream._writableState.finished;
		if (arguments.length === 2) {
		callback = options
		options = {}
		} else if (options == null) {
		options = {}
		} else {
		validateObject(options, 'options')
		}

		var onfinish = function onfinish() {
		writable = false;
		writableEnded = true;
		if (!readable) callback.call(stream);
		};
		validateFunction(callback, 'callback')
		validateAbortSignal(options.signal, 'options.signal')
		callback = once(callback)
		const readable =
		(_options$readable = options.readable) !== null && _options$readable !== undefined
		? _options$readable
		: isReadableNodeStream(stream)
		const writable =
		(_options$writable = options.writable) !== null && _options$writable !== undefined
		? _options$writable
		: isWritableNodeStream(stream)

		var readableEnded = stream._readableState && stream._readableState.endEmitted;
		if (!isNodeStream(stream)) {
		// TODO: Webstreams.
		throw new ERR_INVALID_ARG_TYPE('stream', 'Stream', stream)
		}

		var onend = function onend() {
		readable = false;
		readableEnded = true;
		if (!writable) callback.call(stream);
		};
		const wState = stream._writableState
		const rState = stream._readableState

		var onerror = function onerror(err) {
		callback.call(stream, err);
		};
		const onlegacyfinish = () => {
		if (!stream.writable) {
		onfinish()
		}
		} // TODO (ronag): Improve soft detection to include core modules and
		// common ecosystem modules that do properly emit 'close' but fail
		// this generic check.

		var onclose = function onclose() {
		var err;
		let willEmitClose =
		_willEmitClose(stream) && isReadableNodeStream(stream) === readable && isWritableNodeStream(stream) === writable
		let writableFinished = isWritableFinished(stream, false)

		if (readable && !readableEnded) {
		if (!stream._readableState \|\| !stream._readableState.ended) err = new ERR_STREAM_PREMATURE_CLOSE();
		return callback.call(stream, err);
		const onfinish = () => {
		writableFinished = true // Stream should not be destroyed here. If it is that
		// means that user space is doing something differently and
		// we cannot trust willEmitClose.

		if (stream.destroyed) {
		willEmitClose = false
		}

		if (writable && !writableEnded) {
		if (!stream._writableState \|\| !stream._writableState.ended) err = new ERR_STREAM_PREMATURE_CLOSE();
		return callback.call(stream, err);
		if (willEmitClose && (!stream.readable \|\| readable)) {
		return
		}
		};

		var onrequest = function onrequest() {
		stream.req.on('finish', onfinish);
		};
		if (!readable \|\| readableFinished) {
		callback.call(stream)
		}
		}

		let readableFinished = isReadableFinished(stream, false)

		const onend = () => {
		readableFinished = true // Stream should not be destroyed here. If it is that
		// means that user space is doing something differently and
		// we cannot trust willEmitClose.

		if (stream.destroyed) {
		willEmitClose = false
		}

		if (willEmitClose && (!stream.writable \|\| writable)) {
		return
		}

		if (!writable \|\| writableFinished) {
		callback.call(stream)
		}
		}

		const onerror = (err) => {
		callback.call(stream, err)
		}

		let closed = isClosed(stream)

		const onclose = () => {
		closed = true
		const errored = isWritableErrored(stream) \|\| isReadableErrored(stream)

		if (errored && typeof errored !== 'boolean') {
		return callback.call(stream, errored)
		}

		if (readable && !readableFinished && isReadableNodeStream(stream, true)) {
		if (!isReadableFinished(stream, false)) return callback.call(stream, new ERR_STREAM_PREMATURE_CLOSE())
		}

		if (writable && !writableFinished) {
		if (!isWritableFinished(stream, false)) return callback.call(stream, new ERR_STREAM_PREMATURE_CLOSE())
		}

		callback.call(stream)
		}

		const onrequest = () => {
		stream.req.on('finish', onfinish)
		}

		if (isRequest(stream)) {
		stream.on('complete', onfinish);
		stream.on('abort', onclose);
		if (stream.req) onrequest();else stream.on('request', onrequest);
		} else if (writable && !stream._writableState) {
		stream.on('complete', onfinish)

		if (!willEmitClose) {
		stream.on('abort', onclose)
		}

		if (stream.req) {
		onrequest()
		} else {
		stream.on('request', onrequest)
		}
		} else if (writable && !wState) {
		// legacy streams
		stream.on('end', onlegacyfinish);
		stream.on('close', onlegacyfinish);
		stream.on('end', onlegacyfinish)
		stream.on('close', onlegacyfinish)
		} // Not all streams will emit 'close' after 'aborted'.

		if (!willEmitClose && typeof stream.aborted === 'boolean') {
		stream.on('aborted', onclose)
		}

		stream.on('end', onend);
		stream.on('finish', onfinish);
		if (opts.error !== false) stream.on('error', onerror);
		stream.on('close', onclose);
		return function () {
		stream.removeListener('complete', onfinish);
		stream.removeListener('abort', onclose);
		stream.removeListener('request', onrequest);
		if (stream.req) stream.req.removeListener('finish', onfinish);
		stream.removeListener('end', onlegacyfinish);
		stream.removeListener('close', onlegacyfinish);
		stream.removeListener('finish', onfinish);
		stream.removeListener('end', onend);
		stream.removeListener('error', onerror);
		stream.removeListener('close', onclose);
		};
		stream.on('end', onend)
		stream.on('finish', onfinish)

		if (options.error !== false) {
		stream.on('error', onerror)
		}

		stream.on('close', onclose)

		if (closed) {
		process.nextTick(onclose)
		} else if (
		(wState !== null && wState !== undefined && wState.errorEmitted) \|\|
		(rState !== null && rState !== undefined && rState.errorEmitted)
		) {
		if (!willEmitClose) {
		process.nextTick(onclose)
		}
		} else if (
		!readable &&
		(!willEmitClose \|\| isReadable(stream)) &&
		(writableFinished \|\| isWritable(stream) === false)
		) {
		process.nextTick(onclose)
		} else if (
		!writable &&
		(!willEmitClose \|\| isWritable(stream)) &&
		(readableFinished \|\| isReadable(stream) === false)
		) {
		process.nextTick(onclose)
		} else if (rState && stream.req && stream.aborted) {
		process.nextTick(onclose)
		}

		const cleanup = () => {
		callback = nop
		stream.removeListener('aborted', onclose)
		stream.removeListener('complete', onfinish)
		stream.removeListener('abort', onclose)
		stream.removeListener('request', onrequest)
		if (stream.req) stream.req.removeListener('finish', onfinish)
		stream.removeListener('end', onlegacyfinish)
		stream.removeListener('close', onlegacyfinish)
		stream.removeListener('finish', onfinish)
		stream.removeListener('end', onend)
		stream.removeListener('error', onerror)
		stream.removeListener('close', onclose)
		}

		if (options.signal && !closed) {
		const abort = () => {
		// Keep it because cleanup removes it.
		const endCallback = callback
		cleanup()
		endCallback.call(
		stream,
		new AbortError(undefined, {
		cause: options.signal.reason
		})
		)
		}

		if (options.signal.aborted) {
		process.nextTick(abort)
		} else {
		const originalCallback = callback
		callback = once((...args) => {
		options.signal.removeEventListener('abort', abort)
		originalCallback.apply(stream, args)
		})
		options.signal.addEventListener('abort', abort)
		}
		}

		return cleanup
		}

		module.exports = eos;
		function finished(stream, opts) {
		return new Promise((resolve, reject) => {
		eos(stream, opts, (err) => {
		if (err) {
		reject(err)
		} else {
		resolve()
		}
		})
		})
		}

		module.exports = eos
		module.exports.finished = finished

116

lib/internal/streams/from.js

		@@ -1,64 +0,108 @@
		'use strict';
		'use strict'

		function asyncGeneratorStep(gen, resolve, reject, _next, _throw, key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { Promise.resolve(value).then(_next, _throw); } }
		const { PromisePrototypeThen, SymbolAsyncIterator, SymbolIterator } = require('../../ours/primordials')

		function _asyncToGenerator(fn) { return function () { var self = this, args = arguments; return new Promise(function (resolve, reject) { var gen = fn.apply(self, args); function _next(value) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "next", value); } function _throw(err) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "throw", err); } _next(undefined); }); }; }
		const { ERR_INVALID_ARG_TYPE, ERR_STREAM_NULL_VALUES } = require('../../ours/errors').codes

		function ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); if (enumerableOnly) symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; }); keys.push.apply(keys, symbols); } return keys; }
		function from(Readable, iterable, opts) {
		let iterator

		function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = arguments[i] != null ? arguments[i] : {}; if (i % 2) { ownKeys(Object(source), true).forEach(function (key) { _defineProperty(target, key, source[key]); }); } else if (Object.getOwnPropertyDescriptors) { Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)); } else { ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } } return target; }
		if (typeof iterable === 'string' \|\| iterable instanceof Buffer) {
		return new Readable({
		objectMode: true,
		...opts,

		function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }
		read() {
		this.push(iterable)
		this.push(null)
		}
		})
		}

		var ERR_INVALID_ARG_TYPE = require('../../../errors').codes.ERR_INVALID_ARG_TYPE;
		let isAsync

		function from(Readable, iterable, opts) {
		var iterator;
		if (iterable && iterable[SymbolAsyncIterator]) {
		isAsync = true
		iterator = iterable[SymbolAsyncIterator]()
		} else if (iterable && iterable[SymbolIterator]) {
		isAsync = false
		iterator = iterable[SymbolIterator]()
		} else {
		throw new ERR_INVALID_ARG_TYPE('iterable', ['Iterable'], iterable)
		}

		if (iterable && typeof iterable.next === 'function') {
		iterator = iterable;
		} else if (iterable && iterable[Symbol.asyncIterator]) iterator = iterable[Symbol.asyncIterator]();else if (iterable && iterable[Symbol.iterator]) iterator = iterable[Symbol.iterator]();else throw new ERR_INVALID_ARG_TYPE('iterable', ['Iterable'], iterable);

		var readable = new Readable(_objectSpread({
		objectMode: true
		}, opts)); // Reading boolean to protect against _read
		const readable = new Readable({
		objectMode: true,
		highWaterMark: 1,
		// TODO(ronag): What options should be allowed?
		...opts
		}) // Flag to protect against _read
		// being called before last iteration completion.

		var reading = false;
		let reading = false

		readable._read = function () {
		if (!reading) {
		reading = true;
		next();
		reading = true
		next()
		}
		};
		}

		function next() {
		return _next2.apply(this, arguments);
		readable._destroy = function (error, cb) {
		PromisePrototypeThen(
		close(error),
		() => process.nextTick(cb, error), // nextTick is here in case cb throws
		(e) => process.nextTick(cb, e \|\| error)
		)
		}

		function _next2() {
		_next2 = _asyncToGenerator(function* () {
		async function close(error) {
		const hadError = error !== undefined && error !== null
		const hasThrow = typeof iterator.throw === 'function'

		if (hadError && hasThrow) {
		const { value, done } = await iterator.throw(error)
		await value

		if (done) {
		return
		}
		}

		if (typeof iterator.return === 'function') {
		const { value } = await iterator.return()
		await value
		}
		}

		async function next() {
		for (;;) {
		try {
		var _ref = yield iterator.next(),
		value = _ref.value,
		done = _ref.done;
		const { value, done } = isAsync ? await iterator.next() : iterator.next()

		if (done) {
		readable.push(null);
		} else if (readable.push((yield value))) {
		next();
		readable.push(null)
		} else {
		reading = false;
		const res = value && typeof value.then === 'function' ? await value : value

		if (res === null) {
		reading = false
		throw new ERR_STREAM_NULL_VALUES()
		} else if (readable.push(res)) {
		continue
		} else {
		reading = false
		}
		}
		} catch (err) {
		readable.destroy(err);
		readable.destroy(err)
		}
		});
		return _next2.apply(this, arguments);

		break
		}
		}

		return readable;
		return readable
		}

		module.exports = from;
		module.exports = from

460

lib/internal/streams/pipeline.js

		// Ported from https://github.com/mafintosh/pump with
		// permission from the author, Mathias Buus (@mafintosh).
		'use strict';
		'use strict'

		var eos;
		const abortControllerModule = require('abort-controller')

		function once(callback) {
		var called = false;
		return function () {
		if (called) return;
		called = true;
		callback.apply(void 0, arguments);
		};
		}
		const { ArrayIsArray, Promise, SymbolAsyncIterator } = require('../../ours/primordials')

		var _require$codes = require('../../../errors').codes,
		ERR_MISSING_ARGS = _require$codes.ERR_MISSING_ARGS,
		ERR_STREAM_DESTROYED = _require$codes.ERR_STREAM_DESTROYED;
		const eos = require('./end-of-stream')

		function noop(err) {
		// Rethrow the error if it exists to avoid swallowing it
		if (err) throw err;
		const { once } = require('../../ours/util')

		const destroyImpl = require('./destroy')

		const Duplex = require('./duplex')

		const {
		aggregateTwoErrors,
		codes: { ERR_INVALID_ARG_TYPE, ERR_INVALID_RETURN_VALUE, ERR_MISSING_ARGS, ERR_STREAM_DESTROYED },
		AbortError
		} = require('../../ours/errors')

		const { validateFunction, validateAbortSignal } = require('../validators')

		const { isIterable, isReadable, isReadableNodeStream, isNodeStream } = require('./utils')

		const AbortController = globalThis.AbortController \|\| abortControllerModule.AbortController
		let PassThrough
		let Readable

		function destroyer(stream, reading, writing) {
		let finished = false
		stream.on('close', () => {
		finished = true
		})
		const cleanup = eos(
		stream,
		{
		readable: reading,
		writable: writing
		},
		(err) => {
		finished = !err
		}
		)
		return {
		destroy: (err) => {
		if (finished) return
		finished = true
		destroyImpl.destroyer(stream, err \|\| new ERR_STREAM_DESTROYED('pipe'))
		},
		cleanup
		}
		}

		function isRequest(stream) {
		return stream.setHeader && typeof stream.abort === 'function';
		function popCallback(streams) {
		// Streams should never be an empty array. It should always contain at least
		// a single stream. Therefore optimize for the average case instead of
		// checking for length === 0 as well.
		validateFunction(streams[streams.length - 1], 'streams[stream.length - 1]')
		return streams.pop()
		}

		function destroyer(stream, reading, writing, callback) {
		callback = once(callback);
		var closed = false;
		stream.on('close', function () {
		closed = true;
		});
		if (eos === undefined) eos = require('./end-of-stream');
		eos(stream, {
		readable: reading,
		writable: writing
		}, function (err) {
		if (err) return callback(err);
		closed = true;
		callback();
		});
		var destroyed = false;
		return function (err) {
		if (closed) return;
		if (destroyed) return;
		destroyed = true; // request.destroy just do .end - .abort is what we want
		function makeAsyncIterable(val) {
		if (isIterable(val)) {
		return val
		} else if (isReadableNodeStream(val)) {
		// Legacy streams are not Iterable.
		return fromReadable(val)
		}

		if (isRequest(stream)) return stream.abort();
		if (typeof stream.destroy === 'function') return stream.destroy();
		callback(err \|\| new ERR_STREAM_DESTROYED('pipe'));
		};
		throw new ERR_INVALID_ARG_TYPE('val', ['Readable', 'Iterable', 'AsyncIterable'], val)
		}

		function call(fn) {
		fn();
		async function* fromReadable(val) {
		if (!Readable) {
		Readable = require('./readable')
		}

		yield* Readable.prototype[SymbolAsyncIterator].call(val)
		}

		function pipe(from, to) {
		return from.pipe(to);
		async function pump(iterable, writable, finish, { end }) {
		let error
		let onresolve = null

		const resume = (err) => {
		if (err) {
		error = err
		}

		if (onresolve) {
		const callback = onresolve
		onresolve = null
		callback()
		}
		}

		const wait = () =>
		new Promise((resolve, reject) => {
		if (error) {
		reject(error)
		} else {
		onresolve = () => {
		if (error) {
		reject(error)
		} else {
		resolve()
		}
		}
		}
		})

		writable.on('drain', resume)
		const cleanup = eos(
		writable,
		{
		readable: false
		},
		resume
		)

		try {
		if (writable.writableNeedDrain) {
		await wait()
		}

		for await (const chunk of iterable) {
		if (!writable.write(chunk)) {
		await wait()
		}
		}

		if (end) {
		writable.end()
		}

		await wait()
		finish()
		} catch (err) {
		finish(error !== err ? aggregateTwoErrors(error, err) : err)
		} finally {
		cleanup()
		writable.off('drain', resume)
		}
		}

		function popCallback(streams) {
		if (!streams.length) return noop;
		if (typeof streams[streams.length - 1] !== 'function') return noop;
		return streams.pop();
		function pipeline(...streams) {
		return pipelineImpl(streams, once(popCallback(streams)))
		}

		function pipeline() {
		for (var _len = arguments.length, streams = new Array(_len), _key = 0; _key < _len; _key++) {
		streams[_key] = arguments[_key];
		function pipelineImpl(streams, callback, opts) {
		if (streams.length === 1 && ArrayIsArray(streams[0])) {
		streams = streams[0]
		}

		var callback = popCallback(streams);
		if (Array.isArray(streams[0])) streams = streams[0];

		if (streams.length < 2) {
		throw new ERR_MISSING_ARGS('streams');
		throw new ERR_MISSING_ARGS('streams')
		}

		var error;
		var destroys = streams.map(function (stream, i) {
		var reading = i < streams.length - 1;
		var writing = i > 0;
		return destroyer(stream, reading, writing, function (err) {
		if (!error) error = err;
		if (err) destroys.forEach(call);
		if (reading) return;
		destroys.forEach(call);
		callback(error);
		});
		});
		return streams.reduce(pipe);
		const ac = new AbortController()
		const signal = ac.signal
		const outerSignal = opts === null \|\| opts === undefined ? undefined : opts.signal // Need to cleanup event listeners if last stream is readable
		// https://github.com/nodejs/node/issues/35452

		const lastStreamCleanup = []
		validateAbortSignal(outerSignal, 'options.signal')

		function abort() {
		finishImpl(new AbortError())
		}

		outerSignal === null \|\| outerSignal === undefined ? undefined : outerSignal.addEventListener('abort', abort)
		let error
		let value
		const destroys = []
		let finishCount = 0

		function finish(err) {
		finishImpl(err, --finishCount === 0)
		}

		function finishImpl(err, final) {
		if (err && (!error \|\| error.code === 'ERR_STREAM_PREMATURE_CLOSE')) {
		error = err
		}

		if (!error && !final) {
		return
		}

		while (destroys.length) {
		destroys.shift()(error)
		}

		outerSignal === null \|\| outerSignal === undefined ? undefined : outerSignal.removeEventListener('abort', abort)
		ac.abort()

		if (final) {
		if (!error) {
		lastStreamCleanup.forEach((fn) => fn())
		}

		process.nextTick(callback, error, value)
		}
		}

		let ret

		for (let i = 0; i < streams.length; i++) {
		const stream = streams[i]
		const reading = i < streams.length - 1
		const writing = i > 0
		const end = reading \|\| (opts === null \|\| opts === undefined ? undefined : opts.end) !== false
		const isLastStream = i === streams.length - 1

		if (isNodeStream(stream)) {
		if (end) {
		const { destroy, cleanup } = destroyer(stream, reading, writing)
		destroys.push(destroy)

		if (isReadable(stream) && isLastStream) {
		lastStreamCleanup.push(cleanup)
		}
		} // Catch stream errors that occur after pipe/pump has completed.

		function onError(err) {
		if (err && err.name !== 'AbortError' && err.code !== 'ERR_STREAM_PREMATURE_CLOSE') {
		finish(err)
		}
		}

		stream.on('error', onError)

		if (isReadable(stream) && isLastStream) {
		lastStreamCleanup.push(() => {
		stream.removeListener('error', onError)
		})
		}
		}

		if (i === 0) {
		if (typeof stream === 'function') {
		ret = stream({
		signal
		})

		if (!isIterable(ret)) {
		throw new ERR_INVALID_RETURN_VALUE('Iterable, AsyncIterable or Stream', 'source', ret)
		}
		} else if (isIterable(stream) \|\| isReadableNodeStream(stream)) {
		ret = stream
		} else {
		ret = Duplex.from(stream)
		}
		} else if (typeof stream === 'function') {
		ret = makeAsyncIterable(ret)
		ret = stream(ret, {
		signal
		})

		if (reading) {
		if (!isIterable(ret, true)) {
		throw new ERR_INVALID_RETURN_VALUE('AsyncIterable', `transform[${i - 1}]`, ret)
		}
		} else {
		var _ret

		if (!PassThrough) {
		PassThrough = require('./passthrough')
		} // If the last argument to pipeline is not a stream
		// we must create a proxy stream so that pipeline(...)
		// always returns a stream which can be further
		// composed through `.pipe(stream)`.

		const pt = new PassThrough({
		objectMode: true
		}) // Handle Promises/A+ spec, `then` could be a getter that throws on
		// second use.

		const then = (_ret = ret) === null \|\| _ret === undefined ? undefined : _ret.then

		if (typeof then === 'function') {
		finishCount++
		then.call(
		ret,
		(val) => {
		value = val

		if (val != null) {
		pt.write(val)
		}

		if (end) {
		pt.end()
		}

		process.nextTick(finish)
		},
		(err) => {
		pt.destroy(err)
		process.nextTick(finish, err)
		}
		)
		} else if (isIterable(ret, true)) {
		finishCount++
		pump(ret, pt, finish, {
		end
		})
		} else {
		throw new ERR_INVALID_RETURN_VALUE('AsyncIterable or Promise', 'destination', ret)
		}

		ret = pt
		const { destroy, cleanup } = destroyer(ret, false, true)
		destroys.push(destroy)

		if (isLastStream) {
		lastStreamCleanup.push(cleanup)
		}
		}
		} else if (isNodeStream(stream)) {
		if (isReadableNodeStream(ret)) {
		finishCount += 2
		const cleanup = pipe(ret, stream, finish, {
		end
		})

		if (isReadable(stream) && isLastStream) {
		lastStreamCleanup.push(cleanup)
		}
		} else if (isIterable(ret)) {
		finishCount++
		pump(ret, stream, finish, {
		end
		})
		} else {
		throw new ERR_INVALID_ARG_TYPE('val', ['Readable', 'Iterable', 'AsyncIterable'], ret)
		}

		ret = stream
		} else {
		ret = Duplex.from(stream)
		}
		}

		if (
		(signal !== null && signal !== undefined && signal.aborted) \|\|
		(outerSignal !== null && outerSignal !== undefined && outerSignal.aborted)
		) {
		process.nextTick(abort)
		}

		return ret
		}

		module.exports = pipeline;
		function pipe(src, dst, finish, { end }) {
		src.pipe(dst, {
		end
		})

		if (end) {
		// Compat. Before node v10.12.0 stdio used to throw an error so
		// pipe() did/does not end() stdio destinations.
		// Now they allow it but "secretly" don't close the underlying fd.
		src.once('end', () => dst.end())
		} else {
		finish()
		}

		eos(
		src,
		{
		readable: true,
		writable: false
		},
		(err) => {
		const rState = src._readableState

		if (
		err &&
		err.code === 'ERR_STREAM_PREMATURE_CLOSE' &&
		rState &&
		rState.ended &&
		!rState.errored &&
		!rState.errorEmitted
		) {
		// Some readable streams will emit 'close' before 'end'. However, since
		// this is on the readable side 'end' should still be emitted if the
		// stream has been ended and no error emitted. This should be allowed in
		// favor of backwards compatibility. Since the stream is piped to a
		// destination this should not result in any observable difference.
		// We don't need to check if this is a writable premature close since
		// eos will only fail with premature close on the reading side for
		// duplex streams.
		src.once('end', finish).once('error', finish)
		} else {
		finish(err)
		}
		}
		)
		return eos(
		dst,
		{
		readable: false,
		writable: true
		},
		finish
		)
		}

		module.exports = {
		pipelineImpl,
		pipeline
		}

lib/internal/streams/state.js

		@@ -1,27 +0,33 @@
		'use strict';
		'use strict'

		var ERR_INVALID_OPT_VALUE = require('../../../errors').codes.ERR_INVALID_OPT_VALUE;
		const { MathFloor, NumberIsInteger } = require('../../ours/primordials')

		const { ERR_INVALID_ARG_VALUE } = require('../../ours/errors').codes

		function highWaterMarkFrom(options, isDuplex, duplexKey) {
		return options.highWaterMark != null ? options.highWaterMark : isDuplex ? options[duplexKey] : null;
		return options.highWaterMark != null ? options.highWaterMark : isDuplex ? options[duplexKey] : null
		}

		function getDefaultHighWaterMark(objectMode) {
		return objectMode ? 16 : 16 * 1024
		}

		function getHighWaterMark(state, options, duplexKey, isDuplex) {
		var hwm = highWaterMarkFrom(options, isDuplex, duplexKey);
		const hwm = highWaterMarkFrom(options, isDuplex, duplexKey)

		if (hwm != null) {
		if (!(isFinite(hwm) && Math.floor(hwm) === hwm) \|\| hwm < 0) {
		var name = isDuplex ? duplexKey : 'highWaterMark';
		throw new ERR_INVALID_OPT_VALUE(name, hwm);
		if (!NumberIsInteger(hwm) \|\| hwm < 0) {
		const name = isDuplex ? `options.${duplexKey}` : 'options.highWaterMark'
		throw new ERR_INVALID_ARG_VALUE(name, hwm)
		}

		return Math.floor(hwm);
		return MathFloor(hwm)
		} // Default value


		return state.objectMode ? 16 : 16 * 1024;
		return getDefaultHighWaterMark(state.objectMode)
		}

		module.exports = {
		getHighWaterMark: getHighWaterMark
		};
		getHighWaterMark,
		getDefaultHighWaterMark
		}

129

package.json

		{
		"name": "readable-stream",
		"version": "3.6.0",
		"description": "Streams3, a user-land copy of the stream library from Node.js",
		"main": "readable.js",
		"engines": {
		"node": ">= 6"
		},
		"dependencies": {
		"inherits": "^2.0.3",
		"string_decoder": "^1.1.1",
		"util-deprecate": "^1.0.1"
		},
		"devDependencies": {
		"@babel/cli": "^7.2.0",
		"@babel/core": "^7.2.0",
		"@babel/polyfill": "^7.0.0",
		"@babel/preset-env": "^7.2.0",
		"airtap": "0.0.9",
		"assert": "^1.4.0",
		"bl": "^2.0.0",
		"deep-strict-equal": "^0.2.0",
		"events.once": "^2.0.2",
		"glob": "^7.1.2",
		"gunzip-maybe": "^1.4.1",
		"hyperquest": "^2.1.3",
		"lolex": "^2.6.0",
		"nyc": "^11.0.0",
		"pump": "^3.0.0",
		"rimraf": "^2.6.2",
		"tap": "^12.0.0",
		"tape": "^4.9.0",
		"tar-fs": "^1.16.2",
		"util-promisify": "^2.1.0"
		},
		"scripts": {
		"test": "tap -J --no-esm test/parallel/.js test/ours/.js",
		"ci": "TAP=1 tap --no-esm test/parallel/.js test/ours/.js \| tee test.tap",
		"test-browsers": "airtap --sauce-connect --loopback airtap.local -- test/browser.js",
		"test-browser-local": "airtap --open --local -- test/browser.js",
		"cover": "nyc npm test",
		"report": "nyc report --reporter=lcov",
		"update-browser-errors": "babel -o errors-browser.js errors.js"
		},
		"repository": {
		"type": "git",
		"url": "git://github.com/nodejs/readable-stream"
		},
		"version": "4.0.0",
		"description": "Node.js Streams, a user-land copy of the stream library from Node.js",
		"homepage": "https://github.com/nodejs/readable-stream",
		"license": "MIT",
		"licenses": [
		{
		"type": "MIT",
		"url": "https://choosealicense.com/licenses/mit/"
		}
		],
		"keywords": [
		@@ -54,16 +18,67 @@ "readable",
		],
		"repository": {
		"type": "git",
		"url": "git://github.com/nodejs/readable-stream"
		},
		"bugs": {
		"url": "https://github.com/nodejs/readable-stream/issues"
		},
		"main": "lib/ours/index.js",
		"files": [
		"lib",
		"LICENSE",
		"README.md"
		],
		"browser": {
		"util": false,
		"worker_threads": false,
		"./errors": "./errors-browser.js",
		"./readable.js": "./readable-browser.js",
		"./lib/internal/streams/from.js": "./lib/internal/streams/from-browser.js",
		"./lib/internal/streams/stream.js": "./lib/internal/streams/stream-browser.js"
		"util": "./lib/ours/util.js",
		"./lib/ours/index.js": "./lib/ours/browser.js"
		},
		"nyc": {
		"include": [
		"lib/**.js"
		]
		"scripts": {
		"build": "node build/build.mjs",
		"postbuild": "prettier -w lib test",
		"test": "tap --rcfile=./tap.yml test/parallel/test-.js test/ours/test-.js",
		"test:prepare": "node test/browser/runner-prepare.mjs",
		"test:browsers": "node test/browser/runner-browser.mjs",
		"test:bundlers": "node test/browser/runner-node.mjs",
		"coverage": "c8 -c ./c8.json tap --rcfile=./tap.yml test/parallel/test-.js test/ours/test-.js",
		"format": "prettier -w src lib test",
		"lint": "eslint src"
		},
		"license": "MIT"
		"dependencies": {
		"abort-controller": "^3.0.0"
		},
		"devDependencies": {
		"@babel/core": "^7.17.10",
		"@babel/plugin-proposal-nullish-coalescing-operator": "^7.16.7",
		"@babel/plugin-proposal-optional-chaining": "^7.16.7",
		"@rollup/plugin-commonjs": "^22.0.0",
		"@rollup/plugin-inject": "^4.0.4",
		"@rollup/plugin-node-resolve": "^13.3.0",
		"@sinonjs/fake-timers": "^9.1.2",
		"browserify": "^17.0.0",
		"buffer-es6": "^4.9.3",
		"c8": "^7.11.2",
		"esbuild": "^0.14.39",
		"esbuild-plugin-alias": "^0.2.1",
		"eslint": "^8.15.0",
		"eslint-config-standard": "^17.0.0",
		"eslint-plugin-import": "^2.26.0",
		"eslint-plugin-n": "^15.2.0",
		"eslint-plugin-promise": "^6.0.0",
		"playwright": "^1.21.1",
		"prettier": "^2.6.2",
		"process-es6": "^0.11.6",
		"rollup": "^2.72.1",
		"rollup-plugin-polyfill-node": "^0.9.0",
		"tap": "^16.2.0",
		"tap-mocha-reporter": "^5.0.3",
		"tape": "^5.5.3",
		"tar": "^6.1.11",
		"undici": "^5.1.1",
		"webpack": "^5.72.1",
		"webpack-cli": "^4.9.2"
		},
		"engines": {
		"node": "^12.22.0 \|\| ^14.17.0 \|\| >=16.0.0"
		}
		}

README.md

		# readable-stream

		*Node.js core streams for userland* [![Build Status](https://travis-ci.com/nodejs/readable-stream.svg?branch=master)](https://travis-ci.com/nodejs/readable-stream)
		_Node.js core streams for userland_

		[![npm status](https://img.shields.io/npm/v/readable-stream.svg)](https://npm.im/readable-stream)
		[![node](https://img.shields.io/node/v/readable-stream.svg)](https://www.npmjs.org/package/readable-stream)
		[![Node.js Build](https://github.com/nodejs/readable-stream/workflows/Node.js/badge.svg)](https://github.com/nodejs/readable-stream/actions?query=workflow%3ANode.js)
		[![Browsers Build](https://github.com/nodejs/readable-stream/workflows/Browsers/badge.svg)](https://github.com/nodejs/readable-stream/actions?query=workflow%3ABrowsers)

		[![NPM](https://nodei.co/npm/readable-stream.png?downloads=true&downloadRank=true)](https://nodei.co/npm/readable-stream/)
		[![NPM](https://nodei.co/npm-dl/readable-stream.png?&months=6&height=3)](https://nodei.co/npm/readable-stream/)


		[![Sauce Test Status](https://saucelabs.com/browser-matrix/readabe-stream.svg)](https://saucelabs.com/u/readabe-stream)

		```bash
		npm install --save readable-stream
		npm install readable-stream
		```

		This package is a mirror of the streams implementations in Node.js.
		This package is a mirror of the streams implementations in Node.js 18.0.0.

		Full documentation may be found on the [Node.js website](https://nodejs.org/dist/v10.19.0/docs/api/stream.html).
		Full documentation may be found on the [Node.js website](https://nodejs.org/dist/v18.0.0/docs/api/stream.html).

		If you want to guarantee a stable streams base, regardless of what version of
		Node you, or the users of your libraries are using, use readable-stream only and avoid the "stream" module in Node-core, for background see [this blogpost](http://r.va.gg/2014/06/why-i-dont-use-nodes-core-stream-module.html).
		Node you, or the users of your libraries are using, use readable-stream _only_ and avoid the _"stream"_ module in Node-core, for background see [this blogpost](http://r.va.gg/2014/06/why-i-dont-use-nodes-core-stream-module.html).

		As of version 2.0.0 readable-stream uses semantic versioning.

		## Version 4.x.x

		v4.x.x of `readable-stream` is a cut from Node 18. This version supports Node 12, 14, 16 and 18, as well as evergreen browsers.
		The breaking changes introduced by v4 are composed of the combined breaking changes in:
		* [Node v12](https://nodejs.org/en/blog/release/v12.0.0/)
		* [Node v13](https://nodejs.org/en/blog/release/v13.0.0/)
		* [Node v14](https://nodejs.org/en/blog/release/v14.0.0/)
		* [Node v15](https://nodejs.org/en/blog/release/v15.0.0/)
		* [Node v16](https://nodejs.org/en/blog/release/v16.0.0/)
		* [Node v17](https://nodejs.org/en/blog/release/v17.0.0/)
		* [Node v18](https://nodejs.org/en/blog/release/v18.0.0/)

		This also includes _many_ new features.

		## Version 3.x.x
		@@ -51,8 +63,5 @@
		## Version 2.x.x

		v2.x.x of `readable-stream` is a cut of the stream module from Node 8 (there have been no semver-major changes from Node 4 to 8). This version supports all Node.js versions from 0.8, as well as evergreen browsers and IE 10 & 11.

		### Big Thanks

		Cross-browser Testing Platform and Open Source <3 Provided by [Sauce Labs][sauce]

		# Usage
		@@ -73,3 +82,3 @@
		} = require('readable-stream')
		````
		```

		@@ -81,2 +90,26 @@ Note that `require('stream')` will return `Stream`, while

		## Usage In Browsers

		You will need a bundler like [`browserify`](https://github.com/browserify/browserify#readme), [`webpack`](https://webpack.js.org/), [`parcel`](https://github.com/parcel-bundler/parcel#readme) or similar. With Webpack 5 (which unlike other bundlers does not polyfill Node.js core modules and globals like `process`) you will also need to:

		1. Install polyfills by running `npm install buffer process --save-dev`
		2. Create a [`webpack.config.js`](https://webpack.js.org/guides/getting-started/#using-a-configuration) file containing:

		```js
		const webpack = require('webpack')

		module.exports = {
		plugins: [
		new webpack.ProvidePlugin({
		process: 'process/browser'
		})
		],
		resolve: {
		fallback: {
		buffer: require.resolve('buffer/')
		}
		}
		}
		```

		# Streams Working Group
		@@ -88,23 +121,20 @@

		* Addressing stream issues on the Node.js issue tracker.
		* Authoring and editing stream documentation within the Node.js project.
		* Reviewing changes to stream subclasses within the Node.js project.
		* Redirecting changes to streams from the Node.js project to this
		- Addressing stream issues on the Node.js issue tracker.
		- Authoring and editing stream documentation within the Node.js project.
		- Reviewing changes to stream subclasses within the Node.js project.
		- Redirecting changes to streams from the Node.js project to this
		project.
		* Assisting in the implementation of stream providers within Node.js.
		* Recommending versions of `readable-stream` to be included in Node.js.
		* Messaging about the future of streams to give the community advance
		- Assisting in the implementation of stream providers within Node.js.
		- Recommending versions of `readable-stream` to be included in Node.js.
		- Messaging about the future of streams to give the community advance
		notice of changes.

		<a name="members"></a>

		## Team Members

		* Calvin Metcalf ([@calvinmetcalf](https://github.com/calvinmetcalf)) <calvin.metcalf@gmail.com>
		- Release GPG key: F3EF5F62A87FC27A22E643F714CE4FF5015AA242
		* Mathias Buus ([@mafintosh](https://github.com/mafintosh)) <mathiasbuus@gmail.com>
		* Matteo Collina ([@mcollina](https://github.com/mcollina)) <matteo.collina@gmail.com>
		- Mathias Buus ([@mafintosh](https://github.com/mafintosh)) <mathiasbuus@gmail.com>
		- Matteo Collina ([@mcollina](https://github.com/mcollina)) <matteo.collina@gmail.com>
		- Release GPG key: 3ABC01543F22DD2239285CDD818674489FBC127E
		* Irina Shestak ([@lrlna](https://github.com/lrlna)) <shestak.irina@gmail.com>
		* Yoshua Wyuts ([@yoshuawuyts](https://github.com/yoshuawuyts)) <yoshuawuyts@gmail.com>

		[sauce]: https://saucelabs.com
		- Robert Nagy ([@ronag](https://github.com/ronag)) <ronagy@icloud.com>
		- Vincent Weevers ([@vweevers](https://github.com/vweevers)) <mail@vincentweevers.nl>

CONTRIBUTING.md

errors-browser.js

errors.js

experimentalWarning.js

GOVERNANCE.md

lib/internal/streams/async_iterator.js

lib/internal/streams/from-browser.js

lib/internal/streams/stream-browser.js

lib/internal/streams/stream.js

readable-browser.js

readable.js

New alerts

Fixed alerts

Improved metrics

Worsened metrics

Dependency changes