88 lines
1.6 KiB
JavaScript
88 lines
1.6 KiB
JavaScript
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var Readable = require('stream').Readable;
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var util = require('util');
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function addStream(streams, stream)
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{
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if(!stream.readable) throw new Error('All input streams must be readable');
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if(this._readableState.ended) throw new Error('Adding streams after ended');
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var self = this;
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stream._buffer = [];
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stream.on('data', function(chunk)
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{
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if(this === streams[0])
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self.push(chunk);
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else
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this._buffer.push(chunk);
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});
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stream.on('end', function()
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{
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for(var stream = streams[0];
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stream && stream._readableState.ended;
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stream = streams[0])
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{
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while(stream._buffer.length)
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self.push(stream._buffer.shift());
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streams.shift();
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}
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if(!streams.length) self.push(null);
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});
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stream.on('error', this.emit.bind(this, 'error'));
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streams.push(stream);
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}
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function OrderedStreams(streams, options) {
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if (!(this instanceof(OrderedStreams))) {
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return new OrderedStreams(streams, options);
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}
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streams = streams || [];
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options = options || {};
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options.objectMode = true;
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Readable.call(this, options);
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if(!Array.isArray(streams)) streams = [streams];
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if(!streams.length) return this.push(null); // no streams, close
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var addStream_bind = addStream.bind(this, []);
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this.concat = function()
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{
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Array.prototype.forEach.call(arguments, function(item)
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{
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if(Array.isArray(item))
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item.forEach(addStream_bind);
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else
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addStream_bind(item);
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});
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};
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this.concat(streams);
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}
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util.inherits(OrderedStreams, Readable);
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OrderedStreams.prototype._read = function () {};
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module.exports = OrderedStreams;
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