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2 years ago
'use strict';
var apply = require('../internals/function-apply');
var anObject = require('../internals/an-object');
var create = require('../internals/object-create');
var getMethod = require('../internals/get-method');
var defineBuiltIns = require('../internals/define-built-ins');
var InternalStateModule = require('../internals/internal-state');
var getBuiltIn = require('../internals/get-built-in');
var AsyncIteratorPrototype = require('../internals/async-iterator-prototype');
var Promise = getBuiltIn('Promise');
var ASYNC_FROM_SYNC_ITERATOR = 'AsyncFromSyncIterator';
var setInternalState = InternalStateModule.set;
var getInternalState = InternalStateModule.getterFor(ASYNC_FROM_SYNC_ITERATOR);
var asyncFromSyncIteratorContinuation = function (result, resolve, reject) {
var done = result.done;
Promise.resolve(result.value).then(function (value) {
resolve({ done: done, value: value });
}, reject);
};
var AsyncFromSyncIterator = function AsyncIterator(iterator) {
setInternalState(this, {
type: ASYNC_FROM_SYNC_ITERATOR,
iterator: anObject(iterator),
next: iterator.next
});
};
AsyncFromSyncIterator.prototype = defineBuiltIns(create(AsyncIteratorPrototype), {
next: function next(arg) {
var state = getInternalState(this);
var hasArg = !!arguments.length;
return new Promise(function (resolve, reject) {
var result = anObject(apply(state.next, state.iterator, hasArg ? [arg] : []));
asyncFromSyncIteratorContinuation(result, resolve, reject);
});
},
'return': function (arg) {
var iterator = getInternalState(this).iterator;
var hasArg = !!arguments.length;
return new Promise(function (resolve, reject) {
var $return = getMethod(iterator, 'return');
if ($return === undefined) return resolve({ done: true, value: arg });
var result = anObject(apply($return, iterator, hasArg ? [arg] : []));
asyncFromSyncIteratorContinuation(result, resolve, reject);
});
},
'throw': function (arg) {
var iterator = getInternalState(this).iterator;
var hasArg = !!arguments.length;
return new Promise(function (resolve, reject) {
var $throw = getMethod(iterator, 'throw');
if ($throw === undefined) return reject(arg);
var result = anObject(apply($throw, iterator, hasArg ? [arg] : []));
asyncFromSyncIteratorContinuation(result, resolve, reject);
});
}
});
module.exports = AsyncFromSyncIterator;