1 files changed, 241 insertions, 0 deletions
diff --git a/deps/npm/node_modules/cacache/node_modules/mississippi/node_modules/duplexify/index.js b/deps/npm/node_modules/cacache/node_modules/mississippi/node_modules/duplexify/index.js
new file mode 100644
index 0000000000..8323e654ac
--- /dev/null
+++ b/deps/npm/node_modules/cacache/node_modules/mississippi/node_modules/duplexify/index.js
@@ -0,0 +1,241 @@
+var stream = require('readable-stream')
+var eos = require('end-of-stream')
+var inherits = require('inherits')
+var shift = require('stream-shift')
+
+var SIGNAL_FLUSH = (Buffer.from && Buffer.from !== Uint8Array.from)
+  ? Buffer.from([0])
+  : new Buffer([0])
+
+var onuncork = function(self, fn) {
+  if (self._corked) self.once('uncork', fn)
+  else fn()
+}
+
+var destroyer = function(self, end) {
+  return function(err) {
+    if (err) self._destroyInterval(err)
+    else if (end && !self._ended) self.end()
+  }
+}
+
+var end = function(ws, fn) {
+  if (!ws) return fn()
+  if (ws._writableState && ws._writableState.finished) return fn()
+  if (ws._writableState) return ws.end(fn)
+  ws.end()
+  fn()
+}
+
+var toStreams2 = function(rs) {
+  return new (stream.Readable)({objectMode:true, highWaterMark:16}).wrap(rs)
+}
+
+var Duplexify = function(writable, readable, opts) {
+  if (!(this instanceof Duplexify)) return new Duplexify(writable, readable, opts)
+  stream.Duplex.call(this, opts)
+
+  this._writable = null
+  this._readable = null
+  this._readable2 = null
+
+  this._forwardDestroy = !opts || opts.destroy !== false
+  this._forwardEnd = !opts || opts.end !== false
+  this._corked = 1 // start corked
+  this._ondrain = null
+  this._drained = false
+  this._forwarding = false
+  this._unwrite = null
+  this._unread = null
+  this._ended = false
+  this._error = null
+  this._preferError = false
+
+  this.destroyed = false
+
+  if (writable) this.setWritable(writable)
+  if (readable) this.setReadable(readable)
+}
+
+inherits(Duplexify, stream.Duplex)
+
+Duplexify.obj = function(writable, readable, opts) {
+  if (!opts) opts = {}
+  opts.objectMode = true
+  opts.highWaterMark = 16
+  return new Duplexify(writable, readable, opts)
+}
+
+Duplexify.prototype.cork = function() {
+  if (++this._corked === 1) this.emit('cork')
+}
+
+Duplexify.prototype.uncork = function() {
+  if (this._corked && --this._corked === 0) this.emit('uncork')
+}
+
+Duplexify.prototype.setWritable = function(writable) {
+  if (this._unwrite) this._unwrite()
+
+  if (this.destroyed) {
+    if (writable && writable.destroy) writable.destroy()
+    return
+  }
+
+  if (writable === null || writable === false) {
+    this.end()
+    return
+  }
+
+  var self = this
+  var unend = eos(writable, {writable:true, readable:false}, destroyer(this, this._forwardEnd))
+
+  var ondrain = function() {
+    var ondrain = self._ondrain
+    self._ondrain = null
+    if (ondrain) ondrain()
+  }
+
+  var clear = function() {
+    self._writable.removeListener('drain', ondrain)
+    unend()
+  }
+
+  if (this._unwrite) process.nextTick(ondrain) // force a drain on stream reset to avoid livelocks
+
+  this._writable = writable
+  this._writable.on('drain', ondrain)
+  this._unwrite = clear
+
+  this.uncork() // always uncork setWritable
+}
+
+Duplexify.prototype.setReadable = function(readable) {
+  if (this._unread) this._unread()
+
+  if (this.destroyed) {
+    if (readable && readable.destroy) readable.destroy()
+    return
+  }
+
+  if (readable === null || readable === false) {
+    this.push(null)
+    this.resume()
+    return
+  }
+
+  var self = this
+  var unend = eos(readable, {writable:false, readable:true}, destroyer(this))
+
+  var onreadable = function() {
+    self._forward()
+  }
+
+  var onend = function() {
+    self.push(null)
+  }
+
+  var clear = function() {
+    self._readable2.removeListener('readable', onreadable)
+    self._readable2.removeListener('end', onend)
+    unend()
+  }
+
+  this._drained = true
+  this._readable = readable
+  this._readable2 = readable._readableState ? readable : toStreams2(readable)
+  this._readable2.on('readable', onreadable)
+  this._readable2.on('end', onend)
+  this._unread = clear
+
+  this._forward()
+}
+
+Duplexify.prototype._read = function() {
+  this._drained = true
+  this._forward()
+}
+
+Duplexify.prototype._forward = function() {
+  if (this._forwarding || !this._readable2 || !this._drained) return
+  this._forwarding = true
+
+  var data
+
+  while (this._drained && (data = shift(this._readable2)) !== null) {
+    if (this.destroyed) continue
+    this._drained = this.push(data)
+  }
+
+  this._forwarding = false
+}
+
+Duplexify.prototype.destroy = function(err) {
+  if (this._preferError && !this._error && err) this._error = err
+
+  if (this.destroyed) return
+  this.destroyed = true
+
+  var self = this
+  process.nextTick(function() {
+    self._destroy(self._preferError ? self._error : err)
+  })
+}
+
+Duplexify.prototype._destroyInterval = function(err) {
+  if (this.destroyed) return
+  if (err.message !== 'premature close') return this.destroy(err)
+  this._preferError = true
+  this.destroy(null)
+}
+
+Duplexify.prototype._destroy = function(err) {
+  if (err) {
+    var ondrain = this._ondrain
+    this._ondrain = null
+    if (ondrain) ondrain(err)
+    else this.emit('error', err)
+  }
+
+  if (this._forwardDestroy) {
+    if (this._readable && this._readable.destroy) this._readable.destroy()
+    if (this._writable && this._writable.destroy) this._writable.destroy()
+  }
+
+  this.emit('close')
+}
+
+Duplexify.prototype._write = function(data, enc, cb) {
+  if (this.destroyed) return cb()
+  if (this._corked) return onuncork(this, this._write.bind(this, data, enc, cb))
+  if (data === SIGNAL_FLUSH) return this._finish(cb)
+  if (!this._writable) return cb()
+
+  if (this._writable.write(data) === false) this._ondrain = cb
+  else cb()
+}
+
+
+Duplexify.prototype._finish = function(cb) {
+  var self = this
+  this.emit('preend')
+  onuncork(this, function() {
+    end(self._forwardEnd && self._writable, function() {
+      // haxx to not emit prefinish twice
+      if (self._writableState.prefinished === false) self._writableState.prefinished = true
+      self.emit('prefinish')
+      onuncork(self, cb)
+    })
+  })
+}
+
+Duplexify.prototype.end = function(data, enc, cb) {
+  if (typeof data === 'function') return this.end(null, null, data)
+  if (typeof enc === 'function') return this.end(data, null, enc)
+  this._ended = true
+  if (data) this.write(data)
+  if (!this._writableState.ending) this.write(SIGNAL_FLUSH)
+  return stream.Writable.prototype.end.call(this, cb)
+}
+
+module.exports = Duplexify