21 lines
498 B
JavaScript
21 lines
498 B
JavaScript
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module.exports = shift
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function shift (stream) {
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var rs = stream._readableState
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if (!rs) return null
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return (rs.objectMode || typeof stream._duplexState === 'number') ? stream.read() : stream.read(getStateLength(rs))
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}
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function getStateLength (state) {
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if (state.buffer.length) {
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// Since node 6.3.0 state.buffer is a BufferList not an array
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if (state.buffer.head) {
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return state.buffer.head.data.length
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}
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return state.buffer[0].length
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}
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return state.length
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}
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