73 lines
1.2 KiB
JavaScript
73 lines
1.2 KiB
JavaScript
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/**
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* Module dependencies.
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*/
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var duplexer = require('duplexer2');
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var Stream = require('stream');
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/**
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* Slice reference.
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*/
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var slice = [].slice;
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/**
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* Duplexer options.
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*/
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var opts = {
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bubbleErrors: false
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};
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/**
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* Expose `pipe`.
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*/
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module.exports = pipe;
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/**
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* Pipe.
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*
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* @param {Stream,...,[Function]}
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* @return {Stream}
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* @api public
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*/
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function pipe(){
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if (arguments.length == 1) return arguments[0];
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var streams = slice.call(arguments);
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var cb;
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if ('function' == typeof streams[streams.length - 1]) {
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cb = streams.splice(-1)[0];
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}
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var first = streams[0];
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var last = streams[streams.length - 1];
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var ret;
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if (first.writable && last.readable) ret = duplexer(opts, first, last);
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else if (first.writable) ret = first;
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else if (last.readable) ret = last;
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else ret = new Stream;
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streams.forEach(function(stream, i){
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var next = streams[i+1];
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if (next) stream.pipe(next);
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if (stream != ret) stream.on('error', ret.emit.bind(ret, 'error'));
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});
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if (cb) {
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var ended = false;
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ret.on('error', end);
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last.on('finish', end);
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function end(err){
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if (ended) return;
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ended = true;
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cb(err);
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}
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}
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return ret;
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}
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