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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.// Ported from test262// https://github.com/tc39/test262/blob/276e79d62e8c45bc1e427fc680320c4899eace27/harness/propertyHelper.js// Copyright (C) 2017 Ecma International.  All rights reserved.// This code is governed by the BSD license found in the LICENSE file./*---description: |    Collection of functions used to safely verify the correctness of    property descriptors.defines:  - verifyProperty  - verifyEqualTo  - verifyWritable  - verifyNotWritable  - verifyEnumerable  - verifyNotEnumerable  - verifyConfigurable  - verifyNotConfigurable---*/
// @ts-check
/** * @param {object} obj * @param {string|symbol} name * @param {PropertyDescriptor|undefined} desc * @param {object} [options] * @param {boolean} [options.restore] */function verifyProperty(obj, name, desc, options) {  assert(    arguments.length > 2,    'verifyProperty should receive at least 3 arguments: obj, name, and descriptor'  );
  var originalDesc = Object.getOwnPropertyDescriptor(obj, name);  var nameStr = String(name);
  // Allows checking for undefined descriptor if it's explicitly given.  if (desc === undefined) {    assert.sameValue(      originalDesc,      undefined,      "obj['" + nameStr + "'] descriptor should be undefined"    );
    // desc and originalDesc are both undefined, problem solved;    return true;  }
  assert(    Object.prototype.hasOwnProperty.call(obj, name),    "obj should have an own property " + nameStr  );
  assert.notSameValue(    desc,    null,    "The desc argument should be an object or undefined, null"  );
  assert.sameValue(    typeof desc,    "object",    "The desc argument should be an object or undefined, " + String(desc)  );
  var failures = [];
  if (Object.prototype.hasOwnProperty.call(desc, 'value')) {    if (!isSameValue(desc.value, originalDesc.value)) {      failures.push("descriptor value should be " + desc.value);    }  }
  if (Object.prototype.hasOwnProperty.call(desc, 'enumerable')) {    if (desc.enumerable !== originalDesc.enumerable ||        desc.enumerable !== isEnumerable(obj, name)) {      failures.push('descriptor should ' + (desc.enumerable ? '' : 'not ') + 'be enumerable');    }  }
  if (Object.prototype.hasOwnProperty.call(desc, 'writable')) {    if (desc.writable !== originalDesc.writable ||        desc.writable !== isWritable(obj, name)) {      failures.push('descriptor should ' + (desc.writable ? '' : 'not ') + 'be writable');    }  }
  if (Object.prototype.hasOwnProperty.call(desc, 'configurable')) {    if (desc.configurable !== originalDesc.configurable ||        desc.configurable !== isConfigurable(obj, name)) {      failures.push('descriptor should ' + (desc.configurable ? '' : 'not ') + 'be configurable');    }  }
  assert(!failures.length, failures.join('; '));
  if (options && options.restore) {    Object.defineProperty(obj, name, originalDesc);  }
  return true;}
function isConfigurable(obj, name) {  var hasOwnProperty = Object.prototype.hasOwnProperty;  try {    delete obj[name];  } catch (e) {    if (!(e instanceof TypeError)) {      $ERROR("Expected TypeError, got " + e);    }  }  return !hasOwnProperty.call(obj, name);}
function isEnumerable(obj, name) {  var stringCheck = false;
  if (typeof name === "string") {    for (var x in obj) {      if (x === name) {        stringCheck = true;        break;      }    }  } else {    // skip it if name is not string, works for Symbol names.    stringCheck = true;  }
  return stringCheck &&    Object.prototype.hasOwnProperty.call(obj, name) &&    Object.prototype.propertyIsEnumerable.call(obj, name);}
function isSameValue(a, b) {  if (a === 0 && b === 0) return 1 / a === 1 / b;  if (a !== a && b !== b) return true;
  return a === b;}
var __isArray = Array.isArray;function isWritable(obj, name, verifyProp, value) {  var unlikelyValue = __isArray(obj) && name === "length" ?    Math.pow(2, 32) - 1 :    "unlikelyValue";  var newValue = value || unlikelyValue;  var hadValue = Object.prototype.hasOwnProperty.call(obj, name);  var oldValue = obj[name];  var writeSucceeded;
  try {    obj[name] = newValue;  } catch (e) {    if (!(e instanceof TypeError)) {      $ERROR("Expected TypeError, got " + e);    }  }
  writeSucceeded = isSameValue(obj[verifyProp || name], newValue);
  // Revert the change only if it was successful (in other cases, reverting  // is unnecessary and may trigger exceptions for certain property  // configurations)  if (writeSucceeded) {    if (hadValue) {      obj[name] = oldValue;    } else {      delete obj[name];    }  }
  return writeSucceeded;}
function verifyEqualTo(obj, name, value) {  if (!isSameValue(obj[name], value)) {    $ERROR("Expected obj[" + String(name) + "] to equal " + value +           ", actually " + obj[name]);  }}
function verifyWritable(obj, name, verifyProp, value) {  if (!verifyProp) {    assert(Object.getOwnPropertyDescriptor(obj, name).writable,         "Expected obj[" + String(name) + "] to have writable:true.");  }  if (!isWritable(obj, name, verifyProp, value)) {    $ERROR("Expected obj[" + String(name) + "] to be writable, but was not.");  }}
function verifyNotWritable(obj, name, verifyProp, value) {  if (!verifyProp) {    assert(!Object.getOwnPropertyDescriptor(obj, name).writable,         "Expected obj[" + String(name) + "] to have writable:false.");  }  if (isWritable(obj, name, verifyProp)) {    $ERROR("Expected obj[" + String(name) + "] NOT to be writable, but was.");  }}
function verifyEnumerable(obj, name) {  assert(Object.getOwnPropertyDescriptor(obj, name).enumerable,       "Expected obj[" + String(name) + "] to have enumerable:true.");  if (!isEnumerable(obj, name)) {    $ERROR("Expected obj[" + String(name) + "] to be enumerable, but was not.");  }}
function verifyNotEnumerable(obj, name) {  assert(!Object.getOwnPropertyDescriptor(obj, name).enumerable,       "Expected obj[" + String(name) + "] to have enumerable:false.");  if (isEnumerable(obj, name)) {    $ERROR("Expected obj[" + String(name) + "] NOT to be enumerable, but was.");  }}
function verifyConfigurable(obj, name) {  assert(Object.getOwnPropertyDescriptor(obj, name).configurable,       "Expected obj[" + String(name) + "] to have configurable:true.");  if (!isConfigurable(obj, name)) {    $ERROR("Expected obj[" + String(name) + "] to be configurable, but was not.");  }}
function verifyNotConfigurable(obj, name) {  assert(!Object.getOwnPropertyDescriptor(obj, name).configurable,       "Expected obj[" + String(name) + "] to have configurable:false.");  if (isConfigurable(obj, name)) {    $ERROR("Expected obj[" + String(name) + "] NOT to be configurable, but was.");  }}