tor-browser

Object.js (11376B)

---

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// ES stage 4 proposal
function ObjectGetOwnPropertyDescriptors(O) {
 // Step 1.
 var obj = ToObject(O);

 // Step 2.
 var keys = std_Reflect_ownKeys(obj);

 // Step 3.
 var descriptors = {};

 // Step 4.
 for (var index = 0, len = keys.length; index < len; index++) {
   var key = keys[index];

   // Steps 4.a-b.
   var desc = ObjectGetOwnPropertyDescriptor(obj, key);

   // Step 4.c.
   if (typeof desc !== "undefined") {
     DefineDataProperty(descriptors, key, desc);
   }
 }

 // Step 5.
 return descriptors;
}

/* ES6 draft rev 32 (2015 Feb 2) 19.1.2.9. */
function ObjectGetPrototypeOf(obj) {
 return std_Reflect_getPrototypeOf(ToObject(obj));
}

/* ES6 draft rev 32 (2015 Feb 2) 19.1.2.11. */
function ObjectIsExtensible(obj) {
 return IsObject(obj) && std_Reflect_isExtensible(obj);
}

/* ES2015 19.1.3.5 Object.prototype.toLocaleString */
function Object_toLocaleString() {
 // Step 1.
 var O = this;

 // Step 2.
 return callContentFunction(O.toString, O);
}

// ES 2017 draft bb96899bb0d9ef9be08164a26efae2ee5f25e875 19.1.3.7
function Object_valueOf() {
 // Step 1.
 return ToObject(this);
}

// ES 2018 draft 19.1.3.2
function Object_hasOwnProperty(V) {
 // Implement hasOwnProperty as a pseudo function that becomes a JSOp
 // to easier add an inline cache for this.
 return hasOwn(V, this);
}

// ES 2021 draft rev 0b988b7700de675331ac360d164c978d6ea452ec
// B.2.2.1.1 get Object.prototype.__proto__
function $ObjectProtoGetter() {
 return std_Reflect_getPrototypeOf(ToObject(this));
}
SetCanonicalName($ObjectProtoGetter, "get __proto__");

// ES 2021 draft rev 0b988b7700de675331ac360d164c978d6ea452ec
// B.2.2.1.2 set Object.prototype.__proto__
function $ObjectProtoSetter(proto) {
 return callFunction(std_Object_setProto, this, proto);
}
SetCanonicalName($ObjectProtoSetter, "set __proto__");

// ES7 draft (2016 March 8) B.2.2.3
function ObjectDefineSetter(name, setter) {
 // Step 1.
 var object = ToObject(this);

 // Step 2.
 if (!IsCallable(setter)) {
   ThrowTypeError(JSMSG_BAD_GETTER_OR_SETTER, "setter");
 }

 // Step 4.
 var key = TO_PROPERTY_KEY(name);

 // Steps 3, 5.
 DefineProperty(
   object,
   key,
   ACCESSOR_DESCRIPTOR_KIND | ATTR_ENUMERABLE | ATTR_CONFIGURABLE,
   null,
   setter,
   true
 );

 // Step 6. (implicit)
}

// ES7 draft (2016 March 8) B.2.2.2
function ObjectDefineGetter(name, getter) {
 // Step 1.
 var object = ToObject(this);

 // Step 2.
 if (!IsCallable(getter)) {
   ThrowTypeError(JSMSG_BAD_GETTER_OR_SETTER, "getter");
 }

 // Step 4.
 var key = TO_PROPERTY_KEY(name);

 // Steps 3, 5.
 DefineProperty(
   object,
   key,
   ACCESSOR_DESCRIPTOR_KIND | ATTR_ENUMERABLE | ATTR_CONFIGURABLE,
   getter,
   null,
   true
 );

 // Step 6. (implicit)
}

// ES7 draft (2016 March 8) B.2.2.5
function ObjectLookupSetter(name) {
 // Step 1.
 var object = ToObject(this);

 // Step 2.
 var key = TO_PROPERTY_KEY(name);

 do {
   // Step 3.a.
   var desc = GetOwnPropertyDescriptorToArray(object, key);

   // Step 3.b.
   if (desc) {
     // Step.b.i.
     if (desc[PROP_DESC_ATTRS_AND_KIND_INDEX] & ACCESSOR_DESCRIPTOR_KIND) {
       return desc[PROP_DESC_SETTER_INDEX];
     }

     // Step.b.i.
     return undefined;
   }

   // Step 3.c.
   object = std_Reflect_getPrototypeOf(object);
 } while (object !== null);

 // Step 3.d. (implicit)
}

// ES7 draft (2016 March 8) B.2.2.4
function ObjectLookupGetter(name) {
 // Step 1.
 var object = ToObject(this);

 // Step 2.
 var key = TO_PROPERTY_KEY(name);

 do {
   // Step 3.a.
   var desc = GetOwnPropertyDescriptorToArray(object, key);

   // Step 3.b.
   if (desc) {
     // Step.b.i.
     if (desc[PROP_DESC_ATTRS_AND_KIND_INDEX] & ACCESSOR_DESCRIPTOR_KIND) {
       return desc[PROP_DESC_GETTER_INDEX];
     }

     // Step.b.ii.
     return undefined;
   }

   // Step 3.c.
   object = std_Reflect_getPrototypeOf(object);
 } while (object !== null);

 // Step 3.d. (implicit)
}

// ES2017 draft rev 6859bb9ccaea9c6ede81d71e5320e3833b92cb3e
// 19.1.2.6 Object.getOwnPropertyDescriptor ( O, P )
function ObjectGetOwnPropertyDescriptor(obj, propertyKey) {
 // Steps 1-3.
 var desc = GetOwnPropertyDescriptorToArray(obj, propertyKey);

 // Step 4 (Call to 6.2.4.4 FromPropertyDescriptor).

 // 6.2.4.4 FromPropertyDescriptor, step 1.
 if (!desc) {
   return undefined;
 }

 // 6.2.4.4 FromPropertyDescriptor, steps 2-5, 8-11.
 var attrsAndKind = desc[PROP_DESC_ATTRS_AND_KIND_INDEX];
 if (attrsAndKind & DATA_DESCRIPTOR_KIND) {
   return {
     value: desc[PROP_DESC_VALUE_INDEX],
     writable: !!(attrsAndKind & ATTR_WRITABLE),
     enumerable: !!(attrsAndKind & ATTR_ENUMERABLE),
     configurable: !!(attrsAndKind & ATTR_CONFIGURABLE),
   };
 }

 // 6.2.4.4 FromPropertyDescriptor, steps 2-3, 6-11.
 assert(
   attrsAndKind & ACCESSOR_DESCRIPTOR_KIND,
   "expected accessor property descriptor"
 );
 return {
   get: desc[PROP_DESC_GETTER_INDEX],
   set: desc[PROP_DESC_SETTER_INDEX],
   enumerable: !!(attrsAndKind & ATTR_ENUMERABLE),
   configurable: !!(attrsAndKind & ATTR_CONFIGURABLE),
 };
}

// ES2017 draft rev 6859bb9ccaea9c6ede81d71e5320e3833b92cb3e
// 19.1.2.4 Object.defineProperty ( O, P, Attributes )
// 26.1.3 Reflect.defineProperty ( target, propertyKey, attributes )
function ObjectOrReflectDefineProperty(obj, propertyKey, attributes, strict) {
 // Step 1.
 if (!IsObject(obj)) {
   ThrowTypeError(JSMSG_OBJECT_REQUIRED, DecompileArg(0, obj));
 }

 // Step 2.
 propertyKey = TO_PROPERTY_KEY(propertyKey);

 // Step 3 (Call to 6.2.4.5 ToPropertyDescriptor).

 // 6.2.4.5 ToPropertyDescriptor, step 1.
 if (!IsObject(attributes)) {
   ThrowTypeError(
     JSMSG_OBJECT_REQUIRED_PROP_DESC,
     DecompileArg(2, attributes)
   );
 }

 // 6.2.4.5 ToPropertyDescriptor, step 2.
 var attrs = 0;
 var hasValue = false;
 var value;
 var getter = null;
 var setter = null;

 // 6.2.4.5 ToPropertyDescriptor, steps 3-4.
 if ("enumerable" in attributes) {
   attrs |= attributes.enumerable ? ATTR_ENUMERABLE : ATTR_NONENUMERABLE;
 }

 // 6.2.4.5 ToPropertyDescriptor, steps 5-6.
 if ("configurable" in attributes) {
   attrs |= attributes.configurable ? ATTR_CONFIGURABLE : ATTR_NONCONFIGURABLE;
 }

 // 6.2.4.5 ToPropertyDescriptor, steps 7-8.
 if ("value" in attributes) {
   attrs |= DATA_DESCRIPTOR_KIND;
   value = attributes.value;
   hasValue = true;
 }

 // 6.2.4.5 ToPropertyDescriptor, steps 9-10.
 if ("writable" in attributes) {
   attrs |= DATA_DESCRIPTOR_KIND;
   attrs |= attributes.writable ? ATTR_WRITABLE : ATTR_NONWRITABLE;
 }

 // 6.2.4.5 ToPropertyDescriptor, steps 11-12.
 if ("get" in attributes) {
   attrs |= ACCESSOR_DESCRIPTOR_KIND;
   getter = attributes.get;
   if (!IsCallable(getter) && getter !== undefined) {
     ThrowTypeError(JSMSG_BAD_GET_SET_FIELD, "get");
   }
 }

 // 6.2.4.5 ToPropertyDescriptor, steps 13-14.
 if ("set" in attributes) {
   attrs |= ACCESSOR_DESCRIPTOR_KIND;
   setter = attributes.set;
   if (!IsCallable(setter) && setter !== undefined) {
     ThrowTypeError(JSMSG_BAD_GET_SET_FIELD, "set");
   }
 }

 if (attrs & ACCESSOR_DESCRIPTOR_KIND) {
   // 6.2.4.5 ToPropertyDescriptor, step 15.
   if (attrs & DATA_DESCRIPTOR_KIND) {
     ThrowTypeError(JSMSG_INVALID_DESCRIPTOR);
   }

   // Step 4 (accessor descriptor property).
   return DefineProperty(obj, propertyKey, attrs, getter, setter, strict);
 }

 // Step 4 (data property descriptor with value).
 if (hasValue) {
   // Use the inlinable DefineDataProperty function when possible.
   if (strict) {
     if (
       (attrs & (ATTR_ENUMERABLE | ATTR_CONFIGURABLE | ATTR_WRITABLE)) ===
       (ATTR_ENUMERABLE | ATTR_CONFIGURABLE | ATTR_WRITABLE)
     ) {
       DefineDataProperty(obj, propertyKey, value);
       return true;
     }
   }

   // The fifth argument is set to |null| to mark that |value| is present.
   return DefineProperty(obj, propertyKey, attrs, value, null, strict);
 }

 // Step 4 (generic property descriptor or data property without value).
 return DefineProperty(obj, propertyKey, attrs, undefined, undefined, strict);
}

// ES2017 draft rev 6859bb9ccaea9c6ede81d71e5320e3833b92cb3e
// 19.1.2.4 Object.defineProperty ( O, P, Attributes )
function ObjectDefineProperty(obj, propertyKey, attributes) {
 // Steps 1-4.
 if (!ObjectOrReflectDefineProperty(obj, propertyKey, attributes, true)) {
   // Not standardized yet: https://github.com/tc39/ecma262/pull/688
   return null;
 }

 // Step 5.
 return obj;
}

// Proposal https://tc39.github.io/proposal-object-from-entries/
// 1. Object.fromEntries ( iterable )
function ObjectFromEntries(iter) {
 // We omit the usual step number comments here because they don't help.
 // This implementation inlines AddEntriesFromIterator and
 // CreateDataPropertyOnObject, so it looks more like the polyfill
 // <https://github.com/tc39/proposal-object-from-entries/blob/master/polyfill.js>
 // than the spec algorithm.
 var obj = {};

 for (var pair of allowContentIter(iter)) {
   if (!IsObject(pair)) {
     ThrowTypeError(JSMSG_INVALID_MAP_ITERABLE, "Object.fromEntries");
   }
   DefineDataProperty(obj, pair[0], pair[1]);
 }

 return obj;
}

// Proposal https://github.com/tc39/proposal-accessible-object-hasownproperty
// 1. Object.hasOwn ( O, P )
function ObjectHasOwn(O, P) {
 // Step 1.
 var obj = ToObject(O);
 // Step 2-3.
 return hasOwn(P, obj);
}

// Array Grouping proposal
//
// Object.groupBy ( items, callbackfn )
//
// https://tc39.es/proposal-array-grouping/#sec-object.groupby
function ObjectGroupBy(items, callbackfn) {
 // Step 1. (Call to GroupBy is inlined.)

 // GroupBy, step 1.
 if (IsNullOrUndefined(items)) {
   ThrowTypeError(
     JSMSG_UNEXPECTED_TYPE,
     DecompileArg(0, items),
     items === null ? "null" : "undefined"
   );
 }

 // GroupBy, step 2.
 if (!IsCallable(callbackfn)) {
   ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(1, callbackfn));
 }

 // Step 2.
 var obj = std_Object_create(null);

 // GroupBy, step 3. (Not applicable in our implementation.)

 // GroupBy, step 4.
 var k = 0;

 // GroupBy, steps 4 and 6.
 for (var value of allowContentIter(items)) {
   // GroupBy, step 6.a. (Not applicable)
   assert(k < 2 ** 53 - 1, "out-of-memory happens before k exceeds 2^53 - 1");

   // GroupBy, steps 6.b-d. (Implicit through for-of loop.)

   // GroupBy, step 6.e.
   var key = callContentFunction(callbackfn, undefined, value, k);

   // GroupBy, step 6.f. (Implicit through for-of loop.)

   // GroupBy, step 6.g.i.
   key = TO_PROPERTY_KEY(key);

   // GroupBy, step 6.g.ii. (Implicit through for-of loop.)

   // GroupBy, step 6.h. (Not applicable)

   // GroupBy, step 6.i. (Inlined call to AddValueToKeyedGroup.)
   var elements = obj[key];
   if (elements === undefined) {
     DefineDataProperty(obj, key, [value]);
   } else {
     DefineDataProperty(elements, elements.length, value);
   }

   // GroupBy, step 6.j.
   k += 1;
 }

 // Step 3. (Result object already populated in the previous loop.)

 // Step 4.
 return obj;
}