nodejs/test/parallel/test-stream-pipe-flow-after...

30 lines
754 B
JavaScript

'use strict';
const common = require('../common');
const { Readable, Writable } = require('stream');
// Tests that calling .unpipe() un-blocks a stream that is paused because
// it is waiting on the writable side to finish a write().
const rs = new Readable({
highWaterMark: 1,
// That this gets called at least 20 times is the real test here.
read: common.mustCallAtLeast(() => rs.push('foo'), 20)
});
const ws = new Writable({
highWaterMark: 1,
write: common.mustCall(() => {
// Ignore the callback, this write() simply never finishes.
setImmediate(() => rs.unpipe(ws));
})
});
let chunks = 0;
rs.on('data', common.mustCallAtLeast(() => {
chunks++;
if (chunks >= 20)
rs.pause(); // Finish this test.
}));
rs.pipe(ws);