2025-02-23 23:35:15 -05:00

120 lines
4.0 KiB
JavaScript

'use strict';
var $TypeError = require('es-errors/type');
var AdvanceStringIndex = require('es-abstract/2024/AdvanceStringIndex');
var Call = require('es-abstract/2024/Call');
var CompletionRecord = require('es-abstract/2024/CompletionRecord');
var CreateIteratorFromClosure = require('../aos/CreateIteratorFromClosure');
var GetIteratorDirect = require('../aos/GetIteratorDirect');
var GetMethod = require('es-abstract/2024/GetMethod');
var IsArray = require('es-abstract/2024/IsArray');
var IteratorCloseAll = require('../aos/IteratorCloseAll');
var IteratorStepValue = require('es-abstract/2024/IteratorStepValue');
var ThrowCompletion = require('es-abstract/2024/ThrowCompletion');
var Type = require('es-abstract/2024/Type');
var forEach = require('es-abstract/helpers/forEach');
var getIteratorMethod = require('es-abstract/helpers/getIteratorMethod');
var callBound = require('call-bind/callBound');
var $indexOf = callBound('Array.prototype.indexOf');
var $splice = callBound('Array.prototype.splice');
var iterHelperProto = require('../IteratorHelperPrototype');
var SLOT = require('internal-slot');
module.exports = function concat() {
if (this instanceof concat) {
throw new $TypeError('`Iterator.concat` is not a constructor');
}
var iterables = []; // step 1
forEach(arguments, function (item) { // step 2
if (Type(item) !== 'Object') {
throw new $TypeError('`Iterator.concat` requires all arguments to be objects'); // step 2.1
}
// var method = GetMethod(item, Symbol.iterator); // step 2.2
var method = getIteratorMethod(
{
AdvanceStringIndex: AdvanceStringIndex,
GetMethod: GetMethod,
IsArray: IsArray
},
item
);
if (typeof method === 'undefined') {
throw new $TypeError('`Iterator.concat` requires all arguments to be iterable'); // step 2.3
}
iterables[iterables.length] = { '[[OpenMethod]]': method, '[[Iterable]]': item }; // step 2.4
});
var openIters = []; // step 3
var sentinel = {};
var closeIfAbrupt = function (abruptCompletion) {
if (!(abruptCompletion instanceof CompletionRecord)) {
throw new $TypeError('`abruptCompletion` must be a Completion Record');
}
if (openIters.length > 0) {
IteratorCloseAll(
openIters,
abruptCompletion
);
}
};
var index = 0;
var closure = function () { // step 4
if (index < iterables.length) {
// forEach(iterables, function (iterable) { // step 4.a
var iteratorRecord;
if (openIters.length === 0) {
var iterable = iterables[index];
var iter = Call(iterable['[[OpenMethod]]'], iterable['[[Iterable]]']); // step 4.a.i
if (Type(iter) !== 'Object') {
closeIfAbrupt(ThrowCompletion(new $TypeError('???'))); // step 4.a.ii
}
iteratorRecord = GetIteratorDirect(iter); // step 4.a.iii
iteratorRecord.obj = iterable['[[Iterable]]'];
openIters[openIters.length] = iteratorRecord; // step 4.a.iv
} else {
iteratorRecord = openIters[0];
}
// var innerAlive = true; // step 4.a.v
// while (innerAlive) { // step 4.a.vi
{ // eslint-disable-line no-lone-blocks
// step 4.a.vi.3.a
var innerValue;
try {
innerValue = IteratorStepValue(iteratorRecord); // step 5.b.ix.4.a
} catch (e) {
// innerAlive = false;
$splice(openIters, $indexOf(openIters, iteratorRecord), 1); // step 4.a.vi.2.a
index += 1;
closeIfAbrupt(ThrowCompletion(e)); // step 4.a.vi.3.b
}
if (iteratorRecord['[[Done]]']) {
// innerAlive = false;
$splice(openIters, $indexOf(openIters, iteratorRecord), 1);
index += 1;
return closure();
}
return innerValue; // // step 4.a.vi.3.a
}
// });
}
// return ReturnCompletion(undefined); // step 4.b
return sentinel;
};
SLOT.set(closure, '[[Sentinel]]', sentinel); // for the userland implementation
SLOT.set(closure, '[[CloseIfAbrupt]]', closeIfAbrupt); // for the userland implementation
var gen = CreateIteratorFromClosure(closure, 'Iterator Helper', iterHelperProto, ['[[UnderlyingIterators]]']); // step 5
SLOT.set(gen, '[[UnderlyingIterators]]', []); // step 6
return gen; // step 7
};