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