utils.js (5096B)
1 'use strict'; 2 3 var test = require('tape'); 4 var inspect = require('object-inspect'); 5 var SaferBuffer = require('safer-buffer').Buffer; 6 var forEach = require('for-each'); 7 var utils = require('../lib/utils'); 8 9 test('merge()', function (t) { 10 t.deepEqual(utils.merge(null, true), [null, true], 'merges true into null'); 11 12 t.deepEqual(utils.merge(null, [42]), [null, 42], 'merges null into an array'); 13 14 t.deepEqual(utils.merge({ a: 'b' }, { a: 'c' }), { a: ['b', 'c'] }, 'merges two objects with the same key'); 15 16 var oneMerged = utils.merge({ foo: 'bar' }, { foo: { first: '123' } }); 17 t.deepEqual(oneMerged, { foo: ['bar', { first: '123' }] }, 'merges a standalone and an object into an array'); 18 19 var twoMerged = utils.merge({ foo: ['bar', { first: '123' }] }, { foo: { second: '456' } }); 20 t.deepEqual(twoMerged, { foo: { 0: 'bar', 1: { first: '123' }, second: '456' } }, 'merges a standalone and two objects into an array'); 21 22 var sandwiched = utils.merge({ foo: ['bar', { first: '123', second: '456' }] }, { foo: 'baz' }); 23 t.deepEqual(sandwiched, { foo: ['bar', { first: '123', second: '456' }, 'baz'] }, 'merges an object sandwiched by two standalones into an array'); 24 25 var nestedArrays = utils.merge({ foo: ['baz'] }, { foo: ['bar', 'xyzzy'] }); 26 t.deepEqual(nestedArrays, { foo: ['baz', 'bar', 'xyzzy'] }); 27 28 var noOptionsNonObjectSource = utils.merge({ foo: 'baz' }, 'bar'); 29 t.deepEqual(noOptionsNonObjectSource, { foo: 'baz', bar: true }); 30 31 t.test( 32 'avoids invoking array setters unnecessarily', 33 { skip: typeof Object.defineProperty !== 'function' }, 34 function (st) { 35 var setCount = 0; 36 var getCount = 0; 37 var observed = []; 38 Object.defineProperty(observed, 0, { 39 get: function () { 40 getCount += 1; 41 return { bar: 'baz' }; 42 }, 43 set: function () { setCount += 1; } 44 }); 45 utils.merge(observed, [null]); 46 st.equal(setCount, 0); 47 st.equal(getCount, 1); 48 observed[0] = observed[0]; // eslint-disable-line no-self-assign 49 st.equal(setCount, 1); 50 st.equal(getCount, 2); 51 st.end(); 52 } 53 ); 54 55 t.end(); 56 }); 57 58 test('assign()', function (t) { 59 var target = { a: 1, b: 2 }; 60 var source = { b: 3, c: 4 }; 61 var result = utils.assign(target, source); 62 63 t.equal(result, target, 'returns the target'); 64 t.deepEqual(target, { a: 1, b: 3, c: 4 }, 'target and source are merged'); 65 t.deepEqual(source, { b: 3, c: 4 }, 'source is untouched'); 66 67 t.end(); 68 }); 69 70 test('combine()', function (t) { 71 t.test('both arrays', function (st) { 72 var a = [1]; 73 var b = [2]; 74 var combined = utils.combine(a, b); 75 76 st.deepEqual(a, [1], 'a is not mutated'); 77 st.deepEqual(b, [2], 'b is not mutated'); 78 st.notEqual(a, combined, 'a !== combined'); 79 st.notEqual(b, combined, 'b !== combined'); 80 st.deepEqual(combined, [1, 2], 'combined is a + b'); 81 82 st.end(); 83 }); 84 85 t.test('one array, one non-array', function (st) { 86 var aN = 1; 87 var a = [aN]; 88 var bN = 2; 89 var b = [bN]; 90 91 var combinedAnB = utils.combine(aN, b); 92 st.deepEqual(b, [bN], 'b is not mutated'); 93 st.notEqual(aN, combinedAnB, 'aN + b !== aN'); 94 st.notEqual(a, combinedAnB, 'aN + b !== a'); 95 st.notEqual(bN, combinedAnB, 'aN + b !== bN'); 96 st.notEqual(b, combinedAnB, 'aN + b !== b'); 97 st.deepEqual([1, 2], combinedAnB, 'first argument is array-wrapped when not an array'); 98 99 var combinedABn = utils.combine(a, bN); 100 st.deepEqual(a, [aN], 'a is not mutated'); 101 st.notEqual(aN, combinedABn, 'a + bN !== aN'); 102 st.notEqual(a, combinedABn, 'a + bN !== a'); 103 st.notEqual(bN, combinedABn, 'a + bN !== bN'); 104 st.notEqual(b, combinedABn, 'a + bN !== b'); 105 st.deepEqual([1, 2], combinedABn, 'second argument is array-wrapped when not an array'); 106 107 st.end(); 108 }); 109 110 t.test('neither is an array', function (st) { 111 var combined = utils.combine(1, 2); 112 st.notEqual(1, combined, '1 + 2 !== 1'); 113 st.notEqual(2, combined, '1 + 2 !== 2'); 114 st.deepEqual([1, 2], combined, 'both arguments are array-wrapped when not an array'); 115 116 st.end(); 117 }); 118 119 t.end(); 120 }); 121 122 test('isBuffer()', function (t) { 123 forEach([null, undefined, true, false, '', 'abc', 42, 0, NaN, {}, [], function () {}, /a/g], function (x) { 124 t.equal(utils.isBuffer(x), false, inspect(x) + ' is not a buffer'); 125 }); 126 127 var fakeBuffer = { constructor: Buffer }; 128 t.equal(utils.isBuffer(fakeBuffer), false, 'fake buffer is not a buffer'); 129 130 var saferBuffer = SaferBuffer.from('abc'); 131 t.equal(utils.isBuffer(saferBuffer), true, 'SaferBuffer instance is a buffer'); 132 133 var buffer = Buffer.from ? Buffer.from('abc') : new Buffer('abc'); 134 t.equal(utils.isBuffer(buffer), true, 'real Buffer instance is a buffer'); 135 t.end(); 136 });