1// Copyright Joyent, Inc. and other Node contributors. 2// 3// Permission is hereby granted, free of charge, to any person obtaining a 4// copy of this software and associated documentation files (the 5// "Software"), to deal in the Software without restriction, including 6// without limitation the rights to use, copy, modify, merge, publish, 7// distribute, sublicense, and/or sell copies of the Software, and to permit 8// persons to whom the Software is furnished to do so, subject to the 9// following conditions: 10// 11// The above copyright notice and this permission notice shall be included 12// in all copies or substantial portions of the Software. 13// 14// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 15// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 16// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN 17// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, 18// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR 19// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE 20// USE OR OTHER DEALINGS IN THE SOFTWARE. 21 22'use strict'; 23const common = require('../common'); 24const assert = require('assert'); 25 26const Stream = require('stream'); 27const Readable = Stream.Readable; 28 29const r = new Readable(); 30const N = 256; 31let reads = 0; 32r._read = function(n) { 33 return r.push(++reads === N ? null : Buffer.allocUnsafe(1)); 34}; 35 36r.on('end', common.mustCall()); 37 38const w = new Stream(); 39w.writable = true; 40let buffered = 0; 41w.write = function(c) { 42 buffered += c.length; 43 process.nextTick(drain); 44 return false; 45}; 46 47function drain() { 48 assert(buffered <= 3); 49 buffered = 0; 50 w.emit('drain'); 51} 52 53w.end = common.mustCall(); 54 55r.pipe(w); 56