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How to use returnArguments method in Jest

Best JavaScript code snippet using jest

arguments-apply.js

Source:arguments-apply.js

1// Copyright 2009 the V8 project authors. All rights reserved.2// Redistribution and use in source and binary forms, with or without3// modification, are permitted provided that the following conditions are4// met:5//6//     * Redistributions of source code must retain the above copyright7//       notice, this list of conditions and the following disclaimer.8//     * Redistributions in binary form must reproduce the above9//       copyright notice, this list of conditions and the following10//       disclaimer in the documentation and/or other materials provided11//       with the distribution.12//     * Neither the name of Google Inc. nor the names of its13//       contributors may be used to endorse or promote products derived14//       from this software without specific prior written permission.15//16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.27function ReturnArguments() {28  return arguments;29}30function ReturnReceiver() {31  return this;32}33function Global() {34  return ReturnArguments.apply(this, arguments);35}36assertEquals(0, Global().length);37assertEquals(1, Global(1).length);38assertEquals(2, Global(2)[0]);39assertEquals(2, Global(3, 4).length);40assertEquals(3, Global(3, 4)[0]);41assertEquals(4, Global(3, 4)[1]);42function Local() {43  var object = { f: ReturnArguments };44  return object.f.apply(this, arguments);45}46assertEquals(0, Local().length);47assertEquals(1, Local(1).length);48assertEquals(2, Local(2)[0]);49assertEquals(2, Local(3, 4).length);50assertEquals(3, Local(3, 4)[0]);51assertEquals(4, Local(3, 4)[1]);52function ShadowArguments() {53  var arguments = [3, 4];54  return ReturnArguments.apply(this, arguments);55}56assertEquals(2, ShadowArguments().length);57assertEquals(3, ShadowArguments()[0]);58assertEquals(4, ShadowArguments()[1]);59function NonObjectReceiver(receiver) {60  return ReturnReceiver.apply(receiver, arguments);61}62assertEquals(Object(42), NonObjectReceiver(42));63assertEquals("object", typeof NonObjectReceiver(42));64assertInstanceof(NonObjectReceiver(42), Number);65assertSame(this, NonObjectReceiver(null));66assertSame(this, NonObjectReceiver(void 0));67function FunctionReceiver() {68  return ReturnReceiver.apply(Object, arguments);69}70assertTrue(Object === FunctionReceiver());71function ShadowApply() {72  function f() { return 42; }73  f.apply = function() { return 87; }74  return f.apply(this, arguments);75}76assertEquals(87, ShadowApply());77assertEquals(87, ShadowApply(1));78assertEquals(87, ShadowApply(1, 2));79function CallNonFunction() {80  var object = { apply: Function.prototype.apply };81  return object.apply(this, arguments);82}83assertThrows(CallNonFunction, TypeError);84// Make sure that the stack after the apply optimization is85// in a valid state.86function SimpleStackCheck() {87  var sentinel = 42;88  var result = ReturnArguments.apply(this, arguments);89  assertTrue(result != null);90  assertEquals(42, sentinel);91}92SimpleStackCheck();93function ShadowArgumentsWithConstant() {94  var arguments = null;95  return ReturnArguments.apply(this, arguments);96}97assertEquals(0, ShadowArgumentsWithConstant().length);98assertEquals(0, ShadowArgumentsWithConstant(1).length);99assertEquals(0, ShadowArgumentsWithConstant(1, 2).length);100// Make sure we can deal with unfolding lots of arguments on the101// stack even in the presence of the apply optimizations.102var array = new Array(2048);...

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|it('check_object_of_Car', () => { expect(newCar()).toBeInstanceOf(Car); });| | :- |

Jest Hooks: Setup and Teardown - Learn how to set up conditions which needs to be followed by the test execution and incorporate a tear down function to free resources after the execution is complete.
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Testing React app using Jest Framework - Learn how to test your react web-application with Jest framework in this detailed Jest tutorial.
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