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Direktori : /lib/node_modules/npm/node_modules/minipass/ |
Current File : //lib/node_modules/npm/node_modules/minipass/index.js |
'use strict' const proc = typeof process === 'object' && process ? process : { stdout: null, stderr: null, } const EE = require('events') const Stream = require('stream') const Yallist = require('yallist') const SD = require('string_decoder').StringDecoder const EOF = Symbol('EOF') const MAYBE_EMIT_END = Symbol('maybeEmitEnd') const EMITTED_END = Symbol('emittedEnd') const EMITTING_END = Symbol('emittingEnd') const EMITTED_ERROR = Symbol('emittedError') const CLOSED = Symbol('closed') const READ = Symbol('read') const FLUSH = Symbol('flush') const FLUSHCHUNK = Symbol('flushChunk') const ENCODING = Symbol('encoding') const DECODER = Symbol('decoder') const FLOWING = Symbol('flowing') const PAUSED = Symbol('paused') const RESUME = Symbol('resume') const BUFFERLENGTH = Symbol('bufferLength') const BUFFERPUSH = Symbol('bufferPush') const BUFFERSHIFT = Symbol('bufferShift') const OBJECTMODE = Symbol('objectMode') const DESTROYED = Symbol('destroyed') // TODO remove when Node v8 support drops const doIter = global._MP_NO_ITERATOR_SYMBOLS_ !== '1' const ASYNCITERATOR = doIter && Symbol.asyncIterator || Symbol('asyncIterator not implemented') const ITERATOR = doIter && Symbol.iterator || Symbol('iterator not implemented') // events that mean 'the stream is over' // these are treated specially, and re-emitted // if they are listened for after emitting. const isEndish = ev => ev === 'end' || ev === 'finish' || ev === 'prefinish' const isArrayBuffer = b => b instanceof ArrayBuffer || typeof b === 'object' && b.constructor && b.constructor.name === 'ArrayBuffer' && b.byteLength >= 0 const isArrayBufferView = b => !Buffer.isBuffer(b) && ArrayBuffer.isView(b) module.exports = class Minipass extends Stream { constructor (options) { super() this[FLOWING] = false // whether we're explicitly paused this[PAUSED] = false this.pipes = new Yallist() this.buffer = new Yallist() this[OBJECTMODE] = options && options.objectMode || false if (this[OBJECTMODE]) this[ENCODING] = null else this[ENCODING] = options && options.encoding || null if (this[ENCODING] === 'buffer') this[ENCODING] = null this[DECODER] = this[ENCODING] ? new SD(this[ENCODING]) : null this[EOF] = false this[EMITTED_END] = false this[EMITTING_END] = false this[CLOSED] = false this[EMITTED_ERROR] = null this.writable = true this.readable = true this[BUFFERLENGTH] = 0 this[DESTROYED] = false } get bufferLength () { return this[BUFFERLENGTH] } get encoding () { return this[ENCODING] } set encoding (enc) { if (this[OBJECTMODE]) throw new Error('cannot set encoding in objectMode') if (this[ENCODING] && enc !== this[ENCODING] && (this[DECODER] && this[DECODER].lastNeed || this[BUFFERLENGTH])) throw new Error('cannot change encoding') if (this[ENCODING] !== enc) { this[DECODER] = enc ? new SD(enc) : null if (this.buffer.length) this.buffer = this.buffer.map(chunk => this[DECODER].write(chunk)) } this[ENCODING] = enc } setEncoding (enc) { this.encoding = enc } get objectMode () { return this[OBJECTMODE] } set objectMode (om) { this[OBJECTMODE] = this[OBJECTMODE] || !!om } write (chunk, encoding, cb) { if (this[EOF]) throw new Error('write after end') if (this[DESTROYED]) { this.emit('error', Object.assign( new Error('Cannot call write after a stream was destroyed'), { code: 'ERR_STREAM_DESTROYED' } )) return true } if (typeof encoding === 'function') cb = encoding, encoding = 'utf8' if (!encoding) encoding = 'utf8' // convert array buffers and typed array views into buffers // at some point in the future, we may want to do the opposite! // leave strings and buffers as-is // anything else switches us into object mode if (!this[OBJECTMODE] && !Buffer.isBuffer(chunk)) { if (isArrayBufferView(chunk)) chunk = Buffer.from(chunk.buffer, chunk.byteOffset, chunk.byteLength) else if (isArrayBuffer(chunk)) chunk = Buffer.from(chunk) else if (typeof chunk !== 'string') // use the setter so we throw if we have encoding set this.objectMode = true } // this ensures at this point that the chunk is a buffer or string // don't buffer it up or send it to the decoder if (!this.objectMode && !chunk.length) { if (this[BUFFERLENGTH] !== 0) this.emit('readable') if (cb) cb() return this.flowing } // fast-path writing strings of same encoding to a stream with // an empty buffer, skipping the buffer/decoder dance if (typeof chunk === 'string' && !this[OBJECTMODE] && // unless it is a string already ready for us to use !(encoding === this[ENCODING] && !this[DECODER].lastNeed)) { chunk = Buffer.from(chunk, encoding) } if (Buffer.isBuffer(chunk) && this[ENCODING]) chunk = this[DECODER].write(chunk) if (this.flowing) { // if we somehow have something in the buffer, but we think we're // flowing, then we need to flush all that out first, or we get // chunks coming in out of order. Can't emit 'drain' here though, // because we're mid-write, so that'd be bad. if (this[BUFFERLENGTH] !== 0) this[FLUSH](true) // if we are still flowing after flushing the buffer we can emit the // chunk otherwise we have to buffer it. this.flowing ? this.emit('data', chunk) : this[BUFFERPUSH](chunk) } else this[BUFFERPUSH](chunk) if (this[BUFFERLENGTH] !== 0) this.emit('readable') if (cb) cb() return this.flowing } read (n) { if (this[DESTROYED]) return null try { if (this[BUFFERLENGTH] === 0 || n === 0 || n > this[BUFFERLENGTH]) return null if (this[OBJECTMODE]) n = null if (this.buffer.length > 1 && !this[OBJECTMODE]) { if (this.encoding) this.buffer = new Yallist([ Array.from(this.buffer).join('') ]) else this.buffer = new Yallist([ Buffer.concat(Array.from(this.buffer), this[BUFFERLENGTH]) ]) } return this[READ](n || null, this.buffer.head.value) } finally { this[MAYBE_EMIT_END]() } } [READ] (n, chunk) { if (n === chunk.length || n === null) this[BUFFERSHIFT]() else { this.buffer.head.value = chunk.slice(n) chunk = chunk.slice(0, n) this[BUFFERLENGTH] -= n } this.emit('data', chunk) if (!this.buffer.length && !this[EOF]) this.emit('drain') return chunk } end (chunk, encoding, cb) { if (typeof chunk === 'function') cb = chunk, chunk = null if (typeof encoding === 'function') cb = encoding, encoding = 'utf8' if (chunk) this.write(chunk, encoding) if (cb) this.once('end', cb) this[EOF] = true this.writable = false // if we haven't written anything, then go ahead and emit, // even if we're not reading. // we'll re-emit if a new 'end' listener is added anyway. // This makes MP more suitable to write-only use cases. if (this.flowing || !this[PAUSED]) this[MAYBE_EMIT_END]() return this } // don't let the internal resume be overwritten [RESUME] () { if (this[DESTROYED]) return this[PAUSED] = false this[FLOWING] = true this.emit('resume') if (this.buffer.length) this[FLUSH]() else if (this[EOF]) this[MAYBE_EMIT_END]() else this.emit('drain') } resume () { return this[RESUME]() } pause () { this[FLOWING] = false this[PAUSED] = true } get destroyed () { return this[DESTROYED] } get flowing () { return this[FLOWING] } get paused () { return this[PAUSED] } [BUFFERPUSH] (chunk) { if (this[OBJECTMODE]) this[BUFFERLENGTH] += 1 else this[BUFFERLENGTH] += chunk.length return this.buffer.push(chunk) } [BUFFERSHIFT] () { if (this.buffer.length) { if (this[OBJECTMODE]) this[BUFFERLENGTH] -= 1 else this[BUFFERLENGTH] -= this.buffer.head.value.length } return this.buffer.shift() } [FLUSH] (noDrain) { do {} while (this[FLUSHCHUNK](this[BUFFERSHIFT]())) if (!noDrain && !this.buffer.length && !this[EOF]) this.emit('drain') } [FLUSHCHUNK] (chunk) { return chunk ? (this.emit('data', chunk), this.flowing) : false } pipe (dest, opts) { if (this[DESTROYED]) return const ended = this[EMITTED_END] opts = opts || {} if (dest === proc.stdout || dest === proc.stderr) opts.end = false else opts.end = opts.end !== false const p = { dest: dest, opts: opts, ondrain: _ => this[RESUME]() } this.pipes.push(p) dest.on('drain', p.ondrain) this[RESUME]() // piping an ended stream ends immediately if (ended && p.opts.end) p.dest.end() return dest } addListener (ev, fn) { return this.on(ev, fn) } on (ev, fn) { try { return super.on(ev, fn) } finally { if (ev === 'data' && !this.pipes.length && !this.flowing) this[RESUME]() else if (isEndish(ev) && this[EMITTED_END]) { super.emit(ev) this.removeAllListeners(ev) } else if (ev === 'error' && this[EMITTED_ERROR]) { fn.call(this, this[EMITTED_ERROR]) } } } get emittedEnd () { return this[EMITTED_END] } [MAYBE_EMIT_END] () { if (!this[EMITTING_END] && !this[EMITTED_END] && !this[DESTROYED] && this.buffer.length === 0 && this[EOF]) { this[EMITTING_END] = true this.emit('end') this.emit('prefinish') this.emit('finish') if (this[CLOSED]) this.emit('close') this[EMITTING_END] = false } } emit (ev, data) { // error and close are only events allowed after calling destroy() if (ev !== 'error' && ev !== 'close' && ev !== DESTROYED && this[DESTROYED]) return else if (ev === 'data') { if (!data) return if (this.pipes.length) this.pipes.forEach(p => p.dest.write(data) === false && this.pause()) } else if (ev === 'end') { // only actual end gets this treatment if (this[EMITTED_END] === true) return this[EMITTED_END] = true this.readable = false if (this[DECODER]) { data = this[DECODER].end() if (data) { this.pipes.forEach(p => p.dest.write(data)) super.emit('data', data) } } this.pipes.forEach(p => { p.dest.removeListener('drain', p.ondrain) if (p.opts.end) p.dest.end() }) } else if (ev === 'close') { this[CLOSED] = true // don't emit close before 'end' and 'finish' if (!this[EMITTED_END] && !this[DESTROYED]) return } else if (ev === 'error') { this[EMITTED_ERROR] = data } // TODO: replace with a spread operator when Node v4 support drops const args = new Array(arguments.length) args[0] = ev args[1] = data if (arguments.length > 2) { for (let i = 2; i < arguments.length; i++) { args[i] = arguments[i] } } try { return super.emit.apply(this, args) } finally { if (!isEndish(ev)) this[MAYBE_EMIT_END]() else this.removeAllListeners(ev) } } // const all = await stream.collect() collect () { const buf = [] if (!this[OBJECTMODE]) buf.dataLength = 0 // set the promise first, in case an error is raised // by triggering the flow here. const p = this.promise() this.on('data', c => { buf.push(c) if (!this[OBJECTMODE]) buf.dataLength += c.length }) return p.then(() => buf) } // const data = await stream.concat() concat () { return this[OBJECTMODE] ? Promise.reject(new Error('cannot concat in objectMode')) : this.collect().then(buf => this[OBJECTMODE] ? Promise.reject(new Error('cannot concat in objectMode')) : this[ENCODING] ? buf.join('') : Buffer.concat(buf, buf.dataLength)) } // stream.promise().then(() => done, er => emitted error) promise () { return new Promise((resolve, reject) => { this.on(DESTROYED, () => reject(new Error('stream destroyed'))) this.on('error', er => reject(er)) this.on('end', () => resolve()) }) } // for await (let chunk of stream) [ASYNCITERATOR] () { const next = () => { const res = this.read() if (res !== null) return Promise.resolve({ done: false, value: res }) if (this[EOF]) return Promise.resolve({ done: true }) let resolve = null let reject = null const onerr = er => { this.removeListener('data', ondata) this.removeListener('end', onend) reject(er) } const ondata = value => { this.removeListener('error', onerr) this.removeListener('end', onend) this.pause() resolve({ value: value, done: !!this[EOF] }) } const onend = () => { this.removeListener('error', onerr) this.removeListener('data', ondata) resolve({ done: true }) } const ondestroy = () => onerr(new Error('stream destroyed')) return new Promise((res, rej) => { reject = rej resolve = res this.once(DESTROYED, ondestroy) this.once('error', onerr) this.once('end', onend) this.once('data', ondata) }) } return { next } } // for (let chunk of stream) [ITERATOR] () { const next = () => { const value = this.read() const done = value === null return { value, done } } return { next } } destroy (er) { if (this[DESTROYED]) { if (er) this.emit('error', er) else this.emit(DESTROYED) return this } this[DESTROYED] = true // throw away all buffered data, it's never coming out this.buffer = new Yallist() this[BUFFERLENGTH] = 0 if (typeof this.close === 'function' && !this[CLOSED]) this.close() if (er) this.emit('error', er) else // if no error to emit, still reject pending promises this.emit(DESTROYED) return this } static isStream (s) { return !!s && (s instanceof Minipass || s instanceof Stream || s instanceof EE && ( typeof s.pipe === 'function' || // readable (typeof s.write === 'function' && typeof s.end === 'function') // writable )) } }