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/* 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
// ES2017 draft rev 0e10c9f29fca1385980c08a7d5e7bb3eb775e2e4
// 23.1.1.1 Map, steps 6-8
function MapConstructorInit(iterable) {
var map = this;
// Step 6.a.
var adder = map.set;
// Step 6.b.
if (!IsCallable(adder)) {
ThrowTypeError(JSMSG_NOT_FUNCTION, typeof adder);
}
// Steps 6.c-8.
for (var nextItem of allowContentIter(iterable)) {
// Step 8.d.
if (!IsObject(nextItem)) {
ThrowTypeError(JSMSG_INVALID_MAP_ITERABLE, "Map");
}
// Steps 8.e-j.
callContentFunction(adder, map, nextItem[0], nextItem[1]);
}
}
// ES2018 draft rev f83aa38282c2a60c6916ebc410bfdf105a0f6a54
// 23.1.3.5 Map.prototype.forEach ( callbackfn [ , thisArg ] )
function MapForEach(callbackfn, thisArg = undefined) {
// Step 1.
var M = this;
// Steps 2-3.
if (!IsObject(M) || (M = GuardToMapObject(M)) === null) {
return callFunction(
CallMapMethodIfWrapped,
this,
callbackfn,
thisArg,
"MapForEach"
);
}
// Step 4.
if (!IsCallable(callbackfn)) {
ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, callbackfn));
}
// Steps 5-8.
var entries = callFunction(std_Map_entries, M);
// Inlined: MapIteratorNext
var mapIterationResultPair = globalMapIterationResultPair;
while (true) {
var done = GetNextMapEntryForIterator(entries, mapIterationResultPair);
if (done) {
break;
}
var key = mapIterationResultPair[0];
var value = mapIterationResultPair[1];
mapIterationResultPair[0] = null;
mapIterationResultPair[1] = null;
callContentFunction(callbackfn, thisArg, value, key, M);
}
}
var globalMapIterationResultPair = CreateMapIterationResultPair();
function MapIteratorNext() {
// Step 1.
var O = this;
// Steps 2-3.
if (!IsObject(O) || (O = GuardToMapIterator(O)) === null) {
return callFunction(
CallMapIteratorMethodIfWrapped,
this,
"MapIteratorNext"
);
}
// Steps 4-5 (implemented in GetNextMapEntryForIterator).
// Steps 8-9 (omitted).
var mapIterationResultPair = globalMapIterationResultPair;
var retVal = { value: undefined, done: true };
// Step 10.a, 11.
var done = GetNextMapEntryForIterator(O, mapIterationResultPair);
if (!done) {
// Steps 10.b-c (omitted).
// Step 6.
var itemKind = UnsafeGetInt32FromReservedSlot(O, ITERATOR_SLOT_ITEM_KIND);
var result;
if (itemKind === ITEM_KIND_KEY) {
// Step 10.d.i.
result = mapIterationResultPair[0];
} else if (itemKind === ITEM_KIND_VALUE) {
// Step 10.d.ii.
result = mapIterationResultPair[1];
} else {
// Step 10.d.iii.
assert(itemKind === ITEM_KIND_KEY_AND_VALUE, itemKind);
result = [mapIterationResultPair[0], mapIterationResultPair[1]];
}
mapIterationResultPair[0] = null;
mapIterationResultPair[1] = null;
retVal.value = result;
retVal.done = false;
}
// Steps 7, 12.
return retVal;
}
// ES6 final draft 23.1.2.2.
// Uncloned functions with `$` prefix are allocated as extended function
// to store the original name in `SetCanonicalName`.
function $MapSpecies() {
// Step 1.
return this;
}
SetCanonicalName($MapSpecies, "get [Symbol.species]");
// Array Grouping proposal
//
// Map.groupBy ( items, callbackfn )
//
function MapGroupBy(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 C = GetBuiltinConstructor("Map");
var map = new C();
// 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. (Not applicable)
// GroupBy, step 6.h. (Implicit through std_Map_get.)
// GroupBy, step 6.i. (Inlined call to AddValueToKeyedGroup.)
var elements = callFunction(std_Map_get, map, key);
if (elements === undefined) {
callFunction(std_Map_set, map, key, [value]);
} else {
DefineDataProperty(elements, elements.length, value);
}
// GroupBy, step 6.j.
k += 1;
}
// Step 3. (Result map already populated in the previous loop.)
// Step 4.
return map;
}