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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
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

// 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 )
//
// https://tc39.es/proposal-array-grouping/#sec-map.groupby
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;
}