// Copyright Joyent, Inc. and other Node contributors. // // Permission is hereby granted, free of charge, to any person obtaining a // copy of this software and associated documentation files (the // "Software"), to deal in the Software without restriction, including // without limitation the rights to use, copy, modify, merge, publish, // distribute, sublicense, and/or sell copies of the Software, and to permit // persons to whom the Software is furnished to do so, subject to the // following conditions: // // The above copyright notice and this permission notice shall be included // in all copies or substantial portions of the Software. // // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS // OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN // NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, // DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR // OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE // USE OR OTHER DEALINGS IN THE SOFTWARE. 'use strict'; const common = require('../common'); const { Readable, Writable } = require('stream'); const assert = require('assert'); function toArray(callback) { const stream = new Writable({ objectMode: true }); const list = []; stream.write = function(chunk) { list.push(chunk); }; stream.end = common.mustCall(function() { callback(list); }); return stream; } function fromArray(list) { const r = new Readable({ objectMode: true }); r._read = common.mustNotCall(); list.forEach(function(chunk) { r.push(chunk); }); r.push(null); return r; } { // Verify that objects can be read from the stream const r = fromArray([{ one: '1' }, { two: '2' }]); const v1 = r.read(); const v2 = r.read(); const v3 = r.read(); assert.deepStrictEqual(v1, { one: '1' }); assert.deepStrictEqual(v2, { two: '2' }); assert.strictEqual(v3, null); } { // Verify that objects can be piped into the stream const r = fromArray([{ one: '1' }, { two: '2' }]); r.pipe(toArray(common.mustCall(function(list) { assert.deepStrictEqual(list, [ { one: '1' }, { two: '2' }, ]); }))); } { // Verify that read(n) is ignored const r = fromArray([{ one: '1' }, { two: '2' }]); const value = r.read(2); assert.deepStrictEqual(value, { one: '1' }); } { // Verify that objects can be synchronously read const r = new Readable({ objectMode: true }); const list = [{ one: '1' }, { two: '2' }]; r._read = function(n) { const item = list.shift(); r.push(item || null); }; r.pipe(toArray(common.mustCall(function(list) { assert.deepStrictEqual(list, [ { one: '1' }, { two: '2' }, ]); }))); } { // Verify that objects can be asynchronously read const r = new Readable({ objectMode: true }); const list = [{ one: '1' }, { two: '2' }]; r._read = function(n) { const item = list.shift(); process.nextTick(function() { r.push(item || null); }); }; r.pipe(toArray(common.mustCall(function(list) { assert.deepStrictEqual(list, [ { one: '1' }, { two: '2' }, ]); }))); } { // Verify that strings can be read as objects const r = new Readable({ objectMode: true }); r._read = common.mustNotCall(); const list = ['one', 'two', 'three']; list.forEach(function(str) { r.push(str); }); r.push(null); r.pipe(toArray(common.mustCall(function(array) { assert.deepStrictEqual(array, list); }))); } { // Verify read(0) behavior for object streams const r = new Readable({ objectMode: true }); r._read = common.mustNotCall(); r.push('foobar'); r.push(null); r.pipe(toArray(common.mustCall(function(array) { assert.deepStrictEqual(array, ['foobar']); }))); } { // Verify the behavior of pushing falsey values const r = new Readable({ objectMode: true }); r._read = common.mustNotCall(); r.push(false); r.push(0); r.push(''); r.push(null); r.pipe(toArray(common.mustCall(function(array) { assert.deepStrictEqual(array, [false, 0, '']); }))); } { // Verify high watermark _read() behavior const r = new Readable({ highWaterMark: 6, objectMode: true }); let calls = 0; const list = ['1', '2', '3', '4', '5', '6', '7', '8']; r._read = function(n) { calls++; }; list.forEach(function(c) { r.push(c); }); const v = r.read(); assert.strictEqual(calls, 0); assert.strictEqual(v, '1'); const v2 = r.read(); assert.strictEqual(v2, '2'); const v3 = r.read(); assert.strictEqual(v3, '3'); assert.strictEqual(calls, 1); } { // Verify high watermark push behavior const r = new Readable({ highWaterMark: 6, objectMode: true }); r._read = common.mustNotCall(); for (let i = 0; i < 6; i++) { const bool = r.push(i); assert.strictEqual(bool, i !== 5); } } { // Verify that objects can be written to stream const w = new Writable({ objectMode: true }); w._write = function(chunk, encoding, cb) { assert.deepStrictEqual(chunk, { foo: 'bar' }); cb(); }; w.on('finish', common.mustCall()); w.write({ foo: 'bar' }); w.end(); } { // Verify that multiple objects can be written to stream const w = new Writable({ objectMode: true }); const list = []; w._write = function(chunk, encoding, cb) { list.push(chunk); cb(); }; w.on('finish', common.mustCall(function() { assert.deepStrictEqual(list, [0, 1, 2, 3, 4]); })); w.write(0); w.write(1); w.write(2); w.write(3); w.write(4); w.end(); } { // Verify that strings can be written as objects const w = new Writable({ objectMode: true }); const list = []; w._write = function(chunk, encoding, cb) { list.push(chunk); process.nextTick(cb); }; w.on('finish', common.mustCall(function() { assert.deepStrictEqual(list, ['0', '1', '2', '3', '4']); })); w.write('0'); w.write('1'); w.write('2'); w.write('3'); w.write('4'); w.end(); } { // Verify that stream buffers finish until callback is called const w = new Writable({ objectMode: true }); let called = false; w._write = function(chunk, encoding, cb) { assert.strictEqual(chunk, 'foo'); process.nextTick(function() { called = true; cb(); }); }; w.on('finish', common.mustCall(function() { assert.strictEqual(called, true); })); w.write('foo'); w.end(); }