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'); 25const stream = require('stream'); 26const str = 'asdfasdfasdfasdfasdf'; 27 28const r = new stream.Readable({ 29 highWaterMark: 5, 30 encoding: 'utf8' 31}); 32 33let reads = 0; 34 35function _read() { 36 if (reads === 0) { 37 setTimeout(() => { 38 r.push(str); 39 }, 1); 40 reads++; 41 } else if (reads === 1) { 42 const ret = r.push(str); 43 assert.strictEqual(ret, false); 44 reads++; 45 } else { 46 r.push(null); 47 } 48} 49 50r._read = common.mustCall(_read, 3); 51 52r.on('end', common.mustCall()); 53 54// Push some data in to start. 55// We've never gotten any read event at this point. 56const ret = r.push(str); 57// Should be false. > hwm 58assert(!ret); 59let chunk = r.read(); 60assert.strictEqual(chunk, str); 61chunk = r.read(); 62assert.strictEqual(chunk, null); 63 64r.once('readable', () => { 65 // This time, we'll get *all* the remaining data, because 66 // it's been added synchronously, as the read WOULD take 67 // us below the hwm, and so it triggered a _read() again, 68 // which synchronously added more, which we then return. 69 chunk = r.read(); 70 assert.strictEqual(chunk, str + str); 71 72 chunk = r.read(); 73 assert.strictEqual(chunk, null); 74}); 75