From 5f8de423f190bbb79a62f804151bc24824fa32d8 Mon Sep 17 00:00:00 2001 From: "Matt A. Tobin" Date: Fri, 2 Feb 2018 04:16:08 -0500 Subject: Add m-esr52 at 52.6.0 --- js/src/builtin/Iterator.js | 127 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 js/src/builtin/Iterator.js (limited to 'js/src/builtin/Iterator.js') diff --git a/js/src/builtin/Iterator.js b/js/src/builtin/Iterator.js new file mode 100644 index 000000000..735eec7a0 --- /dev/null +++ b/js/src/builtin/Iterator.js @@ -0,0 +1,127 @@ +/* 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/. */ + +function IteratorIdentity() { + return this; +} + +var LegacyIteratorWrapperMap = new std_WeakMap(); + +function LegacyIteratorNext(arg) { + var iter = callFunction(std_WeakMap_get, LegacyIteratorWrapperMap, this); + try { + return { value: callContentFunction(iter.next, iter, arg), done: false }; + } catch (e) { + if (e instanceof std_StopIteration) + return { value: undefined, done: true }; + throw e; + } +} + +function LegacyIteratorThrow(exn) { + var iter = callFunction(std_WeakMap_get, LegacyIteratorWrapperMap, this); + try { + return { value: callContentFunction(iter.throw, iter, exn), done: false }; + } catch (e) { + if (e instanceof std_StopIteration) + return { value: undefined, done: true }; + throw e; + } +} + +function LegacyIterator(iter) { + callFunction(std_WeakMap_set, LegacyIteratorWrapperMap, this, iter); +} + +function LegacyGeneratorIterator(iter) { + callFunction(std_WeakMap_set, LegacyIteratorWrapperMap, this, iter); +} + +var LegacyIteratorsInitialized = std_Object_create(null); + +function InitLegacyIterators() { + var props = std_Object_create(null); + + props.next = std_Object_create(null); + props.next.value = LegacyIteratorNext; + props.next.enumerable = false; + props.next.configurable = true; + props.next.writable = true; + + props[std_iterator] = std_Object_create(null); + props[std_iterator].value = IteratorIdentity; + props[std_iterator].enumerable = false; + props[std_iterator].configurable = true; + props[std_iterator].writable = true; + + var LegacyIteratorProto = std_Object_create(GetIteratorPrototype(), props); + MakeConstructible(LegacyIterator, LegacyIteratorProto); + + props.throw = std_Object_create(null); + props.throw.value = LegacyIteratorThrow; + props.throw.enumerable = false; + props.throw.configurable = true; + props.throw.writable = true; + + var LegacyGeneratorIteratorProto = std_Object_create(GetIteratorPrototype(), props); + MakeConstructible(LegacyGeneratorIterator, LegacyGeneratorIteratorProto); + + LegacyIteratorsInitialized.initialized = true; +} + +function NewLegacyIterator(iter, wrapper) { + if (!LegacyIteratorsInitialized.initialized) + InitLegacyIterators(); + + return new wrapper(iter); +} + +function LegacyIteratorShim() { + return NewLegacyIterator(ToObject(this), LegacyIterator); +} + +function LegacyGeneratorIteratorShim() { + return NewLegacyIterator(ToObject(this), LegacyGeneratorIterator); +} + +// 7.4.8 CreateListIterator() +function CreateListIterator(array) { + let iterator = NewListIterator(); + UnsafeSetReservedSlot(iterator, ITERATOR_SLOT_TARGET, array); + UnsafeSetReservedSlot(iterator, ITERATOR_SLOT_NEXT_INDEX, 0); + + // 7.4.8.1 ListIterator next() + // The spec requires that we use a new next function per iterator object. + let next = function() { + if (!IsObject(this) || !IsListIterator(this)) + return callFunction(CallListIteratorMethodIfWrapped, this, "ListIteratorNext"); + + if (ActiveFunction() !== UnsafeGetReservedSlot(this, ITERATOR_SLOT_NEXT_METHOD)) + ThrowTypeError(JSMSG_INCOMPATIBLE_METHOD, "next", "method", ToString(this)); + + let array = UnsafeGetObjectFromReservedSlot(this, ITERATOR_SLOT_TARGET); + let index = UnsafeGetReservedSlot(this, ITERATOR_SLOT_NEXT_INDEX); + + if (index >= ToLength(array.length)) { + UnsafeSetReservedSlot(this, ITERATOR_SLOT_NEXT_INDEX, 1/0); + return { value: undefined, done: true }; + } + + UnsafeSetReservedSlot(this, ITERATOR_SLOT_NEXT_INDEX, index + 1); + return { value: array[index], done: false }; + }; + + UnsafeSetReservedSlot(iterator, ITERATOR_SLOT_NEXT_METHOD, next); + iterator.next = next; + + iterator[std_iterator] = ListIteratorIdentity; + return iterator; +} + +function ListIteratorIdentity() { + if (!IsObject(this) || !IsListIterator(this)) + return callFunction(CallListIteratorMethodIfWrapped, this, "ListIteratorIdentity"); + + return this; +} -- cgit v1.2.3