'use strict'; const common = require('../common'); const stream = require('stream'); const assert = require('assert'); const writable = new stream.Writable({ write: common.mustCall(function(chunk, encoding, cb) { assert.strictEqual( readable._readableState.awaitDrain, 0 ); if (chunk.length === 32 * 1024) { // first chunk readable.push(Buffer.alloc(34 * 1024)); // above hwm // We should check if awaitDrain counter is increased in the next // tick, because awaitDrain is incremented after this method finished process.nextTick(() => { assert.strictEqual(readable._readableState.awaitDrain, 1); }); } cb(); }, 3) }); // A readable stream which produces two buffers. const bufs = [Buffer.alloc(32 * 1024), Buffer.alloc(33 * 1024)]; // above hwm const readable = new stream.Readable({ read: function() { while (bufs.length > 0) { this.push(bufs.shift()); } } }); readable.pipe(writable);