Best JavaScript code snippet using chai
test-bi-proxy-ownkeys.js
Source:test-bi-proxy-ownkeys.js  
...21        print('Object.keys:', JSON.stringify(Object.keys(obj)));22    } catch (e) {23        print('Object.keys:', e.name);24    }25    // Object.getOwnPropertyNames() on proxy object also triggers 'ownKeys'26    // trap.  If no such trap exists, property names (enumerable or not)27    // of the *proxy* object are listed (not the proxy target).28    try {29        print('Object.getOwnPropertyNames:', JSON.stringify(Object.getOwnPropertyNames(obj)));30    } catch (e) {31        print('Object.getOwnPropertyNames:', e.name);32    }33}34/*===35basic test36enum keys: string:foo string:bar string:quux37Object.keys: ["foo","bar","quux"]38Object.getOwnPropertyNames: ["foo","bar","quux"]39enum keys: string:0 string:1 string:2 string:prop40Object.keys: ["0","1","2","prop"]41Object.getOwnPropertyNames: ["0","1","2","length","prop"]42proxy.foo: 143enum keys: string:foo string:bar string:quux44Object.keys: ["foo","bar","quux"]45Object.getOwnPropertyNames: ["foo","bar","quux"]46enum keys: string:foo string:bar string:quux47Object.keys: ["foo","bar","quux"]48Object.getOwnPropertyNames: ["foo","bar","quux","nonEnum"]49enum keys: string:foo string:bar string:quux50Object.keys: ["foo","bar","quux"]51Object.getOwnPropertyNames: ["foo","bar","quux"]52ownKeys: true true53enum keys: string:foo string:enumProp54ownKeys: true true55Object.keys: ["foo","enumProp"]56ownKeys: true true57Object.getOwnPropertyNames: ["foo","enumProp","nonEnumProp"]58===*/59function basicEnumerationTest() {60    var target;61    var proxy;62    var handler;63    // Simple target object, no proxies.64    target = { foo: 1, bar: 2, quux: [ 1, 2, 3 ] };65    objDump(target);66    target = [ 'foo', 'bar', 'quux' ];67    target.prop = 'propval';68    objDump(target);69    // Simple target object, proxy without 'enumerate' or 'ownKeys'.70    // Enumeration goes through to the proxy target, same applies to71    // Object.keys() and Object.getOwnPropertyNames().72    target = { foo: 1, bar: 2, quux: [ 1, 2, 3 ] };73    proxy = new Proxy(target, {74    });75    print('proxy.foo:', proxy.foo);76    objDump(proxy);77    // Proxy which returns Object.getOwnPropertyNames() from 'getKeys' trap.78    // This causes enumeration to enumerate 'through' to the target object,79    // except that also non-enumerable properties get enumerated.80    target = { foo: 1, bar: 2, quux: [ 1, 2, 3 ] };81    Object.defineProperty(target, 'nonEnum', {82        value: 'nonenumerable', writable: true, enumerable: false, configurable: true83    });84    handler = {85        getKeys: function (targ) {86            print('getKeys:', this === handler, targ === target);87            return Object.getOwnPropertyNames(targ);88        }89    };90    proxy = new Proxy(target, handler);91    objDump(proxy);92    // Proxy which fabricates non-existent keys in 'getKeys'.93    target = { foo: 1, bar: 2, quux: [ 1, 2, 3 ] };94    handler = {95        getKeys: function (targ) {96            print('getKeys:', this === handler, targ === target);97            return [ 'nosuch1', 'nosuch2' ];98        }99    };100    proxy = new Proxy(target, handler);101    objDump(proxy);102    // Proxy which provides a subset of keys in 'ownKeys'.103    // Enumeration has no trap so it operates on the target directly104    // (and only sees enumerable properties).  Object.keys() and105    // Object.getOwnPropertyNames() use the 'ownKeys' trap.106    //107    // NOTE: ES2015 algorithm for Object.keys() is that the trap result list is108    // processed to check whether or not each key is enumerable (the check109    // uses [[GetOwnProperty]]).  Duktape omits this step now, so110    // Object.keys() and Object.getOwnPropertyNames() return the same result111    // for now.  However, the trap result will still be cleaned up so that112    // non-string keys, gaps, etc will be eliminated.113    target = { foo: 1, bar: 2, quux: [ 1, 2, 3 ] };114    Object.defineProperties(target, {115        enumProp: {116            value: 'enumerable', writable: true, enumerable: true, configurable: true,117        },118        nonEnumProp: {119            value: 'non-enumerable', writable: true, enumerable: false, configurable: true,120        }121    });122    handler = {123        ownKeys: function (targ) {124            print('ownKeys:', this === handler, targ === target);125            return [ 'foo', 'enumProp', 'nonEnumProp' ];126        }127    };128    proxy = new Proxy(target, handler);129    objDump(proxy);130}131try {132    print('basic test');133    basicEnumerationTest();134} catch (e) {135    print(e);136}137/*===138trap result test139fake trap result: 0140enum keys: TypeError141Object.keys: TypeError142Object.getOwnPropertyNames: TypeError143fake trap result: 1144enum keys: TypeError145Object.keys: TypeError146Object.getOwnPropertyNames: TypeError147fake trap result: 2148enum keys: TypeError149Object.keys: TypeError150Object.getOwnPropertyNames: TypeError151fake trap result: 3152enum keys: TypeError153Object.keys: TypeError154Object.getOwnPropertyNames: TypeError155fake trap result: 4156enum keys: TypeError157Object.keys: TypeError158Object.getOwnPropertyNames: TypeError159fake trap result: 5160enum keys: TypeError161Object.keys: TypeError162Object.getOwnPropertyNames: TypeError163fake trap result: 6164enum keys: 165Object.keys: []166Object.getOwnPropertyNames: ["foo","bar","quux"]167fake trap result: 7168enum keys: 169Object.keys: []170Object.getOwnPropertyNames: ["foo","bar","quux"]171fake trap result: 8172enum keys: TypeError173Object.keys: TypeError174Object.getOwnPropertyNames: TypeError175fake trap result: 9176enum keys: TypeError177Object.keys: TypeError178Object.getOwnPropertyNames: TypeError179fake trap result: 10180enum keys: TypeError181Object.keys: TypeError182Object.getOwnPropertyNames: TypeError183fake trap result: 11184enum keys: 185Object.keys: []186Object.getOwnPropertyNames: []187===*/188/* Check handling of various trap result checks: return value must be an object189 * but not necessarily an array.  In ES2016 gaps, non-string/symbol values, etc.190 * cause a TypeError.191 */192function trapResultTest() {193    var gappyArray = [];194    gappyArray[0] = 'foo-gappy';195    gappyArray[10] = 'bar-gappy';196    gappyArray[20] = 'quux-gappy';197    gappyArray.length = 30;198    var results = [199        undefined, null, true, false, 123, 'foo',                            // non-object -> TypeError200        [ 'foo', 'bar', 'quux' ],                                            // array201        { '0': 'foo', '1': 'bar', '2': 'quux', '3': 'baz', 'length': 3 },    // array-like object, 'baz' is skipped (over 'length')202        [ 'foo', undefined, null, true, false, 123, 'quux' ],                // non-string values203        { '0': 'foo', '1': 123, '3': 'quux', 'length': 5 },                  // non-string values and gaps, array-like object204        gappyArray,                                                          // array with gaps205        { '0': 'foo', '1': 'bar', '2': 'quux' },                             // object without 'length'206    ];207    results.forEach(function (trapResult, idx) {208        var target = {209        };210        var proxy;211        print('fake trap result:', idx);212        // print(Duktape.enc('jx', trapResult));213        proxy = new Proxy(target, {214            enumerate: function (targ) { print('"enumerate" trap called, not intended in ES2016'); return trapResult; },215            ownKeys: function (targ) { return trapResult; }216        });217        objDump(proxy);218    });219}220try {221    print('trap result test');222    trapResultTest();223} catch (e) {224    print(e.stack || e);225}226/*===227proxy in Object.keys() etc228foo229foo,bar230Symbol(quux),Symbol(baz)231foo,bar,Symbol(quux),Symbol(baz)232===*/233/* Proxy in Object.keys(), Object.getOwnPropertyNames(), etc. */234function proxyInKeysTest() {235    var proxy;236    var target = {};237    Object.defineProperties(target, {238        foo: { value: 'foo-value', enumerable: true },239        bar: { value: 'bar-value', enumerable: false },240        [ Symbol.for('quux') ]: { value: 'quux-value', enumerable: true },241        [ Symbol.for('baz') ]: { value: 'quux-value', enumerable: false }242    });243    var proxy = new Proxy(target, {244    });245    print(Object.keys(proxy).map(String));246    print(Object.getOwnPropertyNames(proxy).map(String));247    print(Object.getOwnPropertySymbols(proxy).map(String));248    print(Reflect.ownKeys(proxy).map(String));249}250try {251    print('proxy in Object.keys() etc');252    proxyInKeysTest();253} catch (e) {254    print(e.stack || e);...test-bi-typedarray-instance-enum.js
Source:test-bi-typedarray-instance-enum.js  
...42    }43    Object.keys(view).forEach(function (k) {44        print('Object.keys:', k);45    });46    Object.getOwnPropertyNames(view).forEach(function (k) {47        print('Object.getOwnPropertyNames:', k);48    });49}50try {51    typedArrayEnumTest();52} catch (e) {53    print(e.stack || e);...Using AI Code Generation
1var chai = require('chai');2var expect = chai.expect;3describe('Array', function() {4  describe('#indexOf()', function() {5    it('should return -1 when the value is not present', function() {6      expect([1,2,3].indexOf(5)).to.equal(-1);7      expect([1,2,3].indexOf(0)).to.equal(-1);8    });9  });10});11var chai = require('chai');12var expect = chai.expect;13describe('Array', function() {14  describe('#indexOf()', function() {15    it('should return -1 when the value is not present', function() {16      expect([1,2,3].indexOf(5)).to.equal(-1);17      expect([1,2,3].indexOf(0)).to.equal(-1);18    });19  });20});21var chai = require('chai');22var expect = chai.expect;23describe('Array', function() {24  describe('#indexOf()', function() {25    it('should return -1 when the value is not present', function() {26      expect([1,2,3].indexOf(5)).to.equal(-1);27      expect([1,2,3].indexOf(0)).to.equal(-1);28    });29  });30});31var chai = require('chai');32var expect = chai.expect;33describe('Array', function() {34  describe('#indexOf()', function() {35    it('should return -1 when the value is not present', function() {36      expect([1,2,3].indexOf(5)).to.equal(-1);37      expect([1,2,3].indexOf(0)).to.equal(-1);38    });39  });40});41var chai = require('chai');42var expect = chai.expect;43describe('Array', function() {44  describe('#indexOf()', function() {45    it('should return -1 when the value is not present', function() {46      expect([1,2,3].indexOf(5)).to.equal(-1);47      expect([1,2,3].indexOf(0)).to.equal(-1);48    });49  });50});51var chai = require('chai');52var expect = chai.expect;Using AI Code Generation
1const assert = require('chai').assert;2const _ = require('../index');3describe("#head", () => {4  it("returns 1 for [1, 2, 3]", () => {5    assert.strictEqual(_.head([1, 2, 3]), 1);6  });7});Using AI Code Generation
1var obj = {2};3var obj = {4};5var obj = {6};7var obj = {8};9var obj = {10};11var obj = {12};13var obj = {14};15var obj = {16};17console.log(Object.getOwnPropertyNames(obj).length === 3 && Object.getOwnPropertyNamesUsing AI Code Generation
1var obj = {2};3var prop = Object.getOwnPropertyNames(obj);4console.log(prop);5var obj = {};6var a = Symbol('a');7var b = Symbol.for('b');8obj[a] = 'localSymbol';9obj[b] = 'globalSymbol';10var objectSymbols = Object.getOwnPropertySymbols(obj);11console.log(objectSymbols);12var prototype = {};13var obj = Object.create(prototype);14console.log(Object.getPrototypeOf(obj) === prototype);15console.log(Object.is('foo', 'foo'));16console.log(Object.is({}, {}));17var empty = {};18console.log(Object.isExtensible(empty));19var object1 = {20};21Object.freeze(object1);22console.log(Object.isFrozen(object1));23var object2 = {24};25Object.seal(object2);26console.log(Object.isSealed(object2));27var obj = {28};29console.log(Object.keys(obj));30var object3 = {};31Object.preventExtensions(object3);32console.log(Object.isExtensible(object3));33var object4 = {34};35Object.seal(object4);36object4.property2 = 33;37console.log(object4.property2);38var prototype = {};39var obj = Object.create(prototype);40console.log(Object.getPrototypeOf(obj) === prototype);41var obj = {Using AI Code Generation
1var obj = {a: 1, b: 2, c: 3};2var obj2 = Object.create(obj);3obj2.d = 4;4var obj = {a: 1, b: 2, c: 3};5var obj2 = Object.create(obj);6obj2.d = 4;7var sym1 = Symbol('a');8var sym2 = Symbol('b');9obj2[sym1] = 'foo';10obj2[sym2] = 'bar';11var obj = {a: 1, b: 2, c: 3};12var obj2 = Object.create(obj);13obj2.d = 4;14var sym1 = Symbol('a');15var sym2 = Symbol('b');16obj2[sym1] = 'foo';17obj2[sym2] = 'bar';18var obj = {a: 1, b: 2, c: 3};19var obj2 = Object.create(obj);20obj2.d = 4;21var sym1 = Symbol('a');22var sym2 = Symbol('b');23obj2[sym1] = 'foo';24obj2[sym2] = 'bar';25var obj = {a: 1, b: 2, c: 3};26var obj2 = Object.create(obj);27obj2.d = 4;28var sym1 = Symbol('a');29var sym2 = Symbol('b');30obj2[sym1] = 'foo';31obj2[sym2] = 'bar';32var obj = {a: 1, b: 2, c: 3};33var obj2 = Object.create(objUsing AI Code Generation
1var obj = {2};3console.log(Object.getOwnPropertyNames(obj).map(function (k) {4  return obj[k];5}));6var obj = {7};8console.log(Object.getOwnPropertyNames(obj).map(function (k) {9  return obj[k] * 2;10}));11var obj = {12};13console.log(Object.getOwnPropertyNames(obj).map(function (k) {14  return obj[k] * 2;15}).filter(function (v) {16  return v > 3;17}));18var obj = {19};20console.log(Object.getOwnPropertyNames(obj).map(function (k) {21  return obj[k] * 2;22}).filter(function (v) {23  return v > 3;24}).reduce(function (a, b) {25  return a + b;26}));27var obj = {28};29console.log(Object.getOwnPropertyNames(obj).map(function (k) {30  return obj[k] * 2;31}).filter(function (v) {32  return v > 3;33}).reduce(function (a, b) {34  return a + b;35}, 100));36var obj = {37};38console.log(Object.getOwnPropertyNames(obj).map(function (k) {39  return obj[k] * 2;40}).filter(function (v) {41  return v > 3;42}).reduce(function (a, b) {43  return a + b;44}, 100).toString());Using AI Code Generation
1const assert = require("chai").assert;2const obj = {3};4describe("Test for property", () => {5  it("should return true if property exists", () => {6    assert.isTrue(Object.getOwnPropertyNames(obj).includes("name"));7  });8  it("should return false if property does not exist", () => {9    assert.isFalse(Object.getOwnPropertyNames(obj).includes("address"));10  });11});12const assert = require("chai").assert;13const obj = {14};15describe("Test for property", () => {16  it("should return true if property exists", () => {17    assert.isTrue(Object.keys(obj).includes("name"));18  });19  it("should return false if property does not exist", () => {20    assert.isFalse(Object.keys(obj).includes("address"));21  });22});23const assert = require("chai").assert;24const obj = {25};26describe("Test for property", () => {27  it("should return true if property exists", () => {28    assert.isTrue(Object.getOwnPropertyNames(obj).includes("name"));29  });30  it("should return false if property does not exist", () => {31    assert.isFalse(Object.getOwnPropertyNames(obj).includes("address"));32  });33});34const assert = require("chai").assert;35const obj = {36};37describe("Test for property", () => {38  it("should return true if property exists", () => {39    assert.isTrue(Object.keys(obj).includes("name"));40  });41  it("should return false if property does not exist", () => {42    assert.isFalse(Object.keys(obj).includes("address"));43  });44});Learn to execute automation testing from scratch with LambdaTest Learning Hub. Right from setting up the prerequisites to run your first automation test, to following best practices and diving deeper into advanced test scenarios. LambdaTest Learning Hubs compile a list of step-by-step guides to help you be proficient with different test automation frameworks i.e. Selenium, Cypress, TestNG etc.
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