Something went wrong. Try again.
MIRROR: javascript for 🐜's, a tiny runtime with big ambitions ant.themackabu.dev
Something went wrong. Try again.
JavaScript
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128import { test, testDeep, testThrows, summary } from './helpers.js';
console.log('Object Tests\n');
let obj = { a: 1, b: 2, c: 3 };test('object property access', obj.a, 1);test('object bracket access', obj['b'], 2);test('object property count', Object.keys(obj).length, 3);
obj.d = 4;test('add property', obj.d, 4);
obj.a = 10;test('modify property', obj.a, 10);
delete obj.d;test('delete property', obj.d, undefined);
test('in operator true', 'a' in obj, true);test('in operator false', 'z' in obj, false);
testDeep('Object.keys', Object.keys({ x: 1, y: 2 }), ['x', 'y']);testDeep('Object.values', Object.values({ x: 1, y: 2 }), [1, 2]);testDeep('Object.entries', Object.entries({ x: 1 }), [['x', 1]]);
let merged = Object.assign({}, { a: 1 }, { b: 2 });test('Object.assign a', merged.a, 1);test('Object.assign b', merged.b, 2);
let nested = { a: { b: { c: 1 } } };test('nested access', nested.a.b.c, 1);
let computed = { ['key' + 1]: 'value' };test('computed property', computed.key1, 'value');
let short = 'hello';let shorthand = { short };test('shorthand property', shorthand.short, 'hello');
let methodObj = { value: 42, getValue() { return this.value; }};test('method shorthand', methodObj.getValue(), 42);
let source = { a: 1, b: 2 };let spread = { ...source, c: 3 };test('spread a', spread.a, 1);test('spread c', spread.c, 3);
let { a, b } = { a: 1, b: 2, c: 3 };test('destructuring a', a, 1);test('destructuring b', b, 2);
let { x: renamed } = { x: 5 };test('destructuring rename', renamed, 5);
let { y = 10 } = {};test('destructuring default', y, 10);
test('hasOwnProperty true', { a: 1 }.hasOwnProperty('a'), true);test('hasOwnProperty false', { a: 1 }.hasOwnProperty('b'), false);
let frozen = Object.freeze({ a: 1 });test('Object.isFrozen', Object.isFrozen(frozen), true);
let sealed = Object.seal({ a: 1 });test('Object.isSealed', Object.isSealed(sealed), true);
let proto = { inherited: true };let child = Object.create(proto);test('Object.create inherits', child.inherited, true);
test('Object.getPrototypeOf', Object.getPrototypeOf([]) === Array.prototype, true);
testDeep( 'Object.fromEntries', Object.fromEntries([ ['a', 1], ['b', 2] ]), { a: 1, b: 2 });
let descriptorSource = {};const descriptorSymbol = Symbol('descriptor');Object.defineProperty(descriptorSource, 'hidden', { value: 42, enumerable: false, writable: false, configurable: false});Object.defineProperty(descriptorSource, 'computed', { get() { return 7; }, enumerable: true, configurable: true});descriptorSource.visible = 'yes';descriptorSource[descriptorSymbol] = 'symbol value';
const descriptors = Object.getOwnPropertyDescriptors(descriptorSource);test('Object.getOwnPropertyDescriptors exists', typeof Object.getOwnPropertyDescriptors, 'function');test('descriptors data value', descriptors.visible.value, 'yes');test('descriptors hidden value', descriptors.hidden.value, 42);test('descriptors hidden enumerable', descriptors.hidden.enumerable, false);test('descriptors hidden writable', descriptors.hidden.writable, false);test('descriptors hidden configurable', descriptors.hidden.configurable, false);test('descriptors accessor getter', typeof descriptors.computed.get, 'function');test('descriptors accessor enumerable', descriptors.computed.enumerable, true);test('descriptors symbol value', descriptors[descriptorSymbol].value, 'symbol value');
const arrayDescriptors = Object.getOwnPropertyDescriptors(['item']);test('array descriptor index value', arrayDescriptors[0].value, 'item');test('array descriptor length value', arrayDescriptors.length.value, 1);const proxyUndefinedDescriptor = new Proxy({ a: 1 }, { getOwnPropertyDescriptor() {}});test('Object.getOwnPropertyDescriptors skips undefined proxy descriptors', Object.getOwnPropertyDescriptors(proxyUndefinedDescriptor).hasOwnProperty('a'), false);testThrows('Object.getOwnPropertyDescriptors throws without argument', () => Object.getOwnPropertyDescriptors());testThrows('Object.getOwnPropertyDescriptors throws on null', () => Object.getOwnPropertyDescriptors(null));test('Object.getOwnPropertyDescriptors boxes number primitive', typeof Object.getOwnPropertyDescriptors(1), 'object');
summary();