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-rw-r--r--node_modules/cloneable-readable/index.js110
1 files changed, 110 insertions, 0 deletions
diff --git a/node_modules/cloneable-readable/index.js b/node_modules/cloneable-readable/index.js
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+'use strict'
+
+var through2 = require('through2')
+var inherits = require('inherits')
+var nextTick = require('process-nextick-args')
+var Ctor = through2.ctor()
+
+function Cloneable (stream, opts) {
+ if (!(this instanceof Cloneable)) {
+ return new Cloneable(stream, opts)
+ }
+
+ var objectMode = stream._readableState.objectMode
+ this._original = stream
+ this._clonesCount = 1
+
+ opts = opts || {}
+ opts.objectMode = objectMode
+
+ Ctor.call(this, opts)
+
+ forwardDestroy(stream, this)
+
+ this.on('newListener', onData)
+}
+
+inherits(Cloneable, Ctor)
+
+function onData (event, listener) {
+ if (event === 'data' || event === 'readable') {
+ this.removeListener('newListener', onData)
+ nextTick(clonePiped, this)
+ }
+}
+
+Cloneable.prototype.clone = function () {
+ if (!this._original) {
+ throw new Error('already started')
+ }
+
+ this._clonesCount++
+
+ // the events added by the clone should not count
+ // for starting the flow
+ this.removeListener('newListener', onData)
+ var clone = new Clone(this)
+ this.on('newListener', onData)
+
+ return clone
+}
+
+function forwardDestroy (src, dest) {
+ src.on('error', destroy)
+ src.on('close', destroy)
+
+ function destroy (err) {
+ dest.destroy(err)
+ }
+}
+
+function clonePiped (that) {
+ if (--that._clonesCount === 0 && !that._destroyed) {
+ that._original.pipe(that)
+ that._original = undefined
+ }
+}
+
+function Clone (parent, opts) {
+ if (!(this instanceof Clone)) {
+ return new Clone(parent, opts)
+ }
+
+ var objectMode = parent._readableState.objectMode
+
+ opts = opts || {}
+ opts.objectMode = objectMode
+
+ this.parent = parent
+
+ Ctor.call(this, opts)
+
+ forwardDestroy(this.parent, this)
+
+ parent.pipe(this)
+
+ // the events added by the clone should not count
+ // for starting the flow
+ // so we add the newListener handle after we are done
+ this.on('newListener', onDataClone)
+}
+
+function onDataClone (event, listener) {
+ // We start the flow once all clones are piped or destroyed
+ if (event === 'data' || event === 'readable' || event === 'close') {
+ nextTick(clonePiped, this.parent)
+ this.removeListener('newListener', onDataClone)
+ }
+}
+
+inherits(Clone, Ctor)
+
+Clone.prototype.clone = function () {
+ return this.parent.clone()
+}
+
+Cloneable.isCloneable = function (stream) {
+ return stream instanceof Cloneable || stream instanceof Clone
+}
+
+module.exports = Cloneable