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1 files changed, 50 insertions, 0 deletions

diff --git a/src/node_modules/es-abstract/2019/IteratorClose.js b/src/node_modules/es-abstract/2019/IteratorClose.js
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index 0000000..35c8c2b
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+++ b/src/node_modules/es-abstract/2019/IteratorClose.js
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+'use strict';
+
+var GetIntrinsic = require('../GetIntrinsic');
+
+var $TypeError = GetIntrinsic('%TypeError%');
+
+var Call = require('./Call');
+var GetMethod = require('./GetMethod');
+var IsCallable = require('./IsCallable');
+var Type = require('./Type');
+
+// https://ecma-international.org/ecma-262/6.0/#sec-iteratorclose
+
+module.exports = function IteratorClose(iterator, completion) {
+	if (Type(iterator) !== 'Object') {
+		throw new $TypeError('Assertion failed: Type(iterator) is not Object');
+	}
+	if (!IsCallable(completion)) {
+		throw new $TypeError('Assertion failed: completion is not a thunk for a Completion Record');
+	}
+	var completionThunk = completion;
+
+	var iteratorReturn = GetMethod(iterator, 'return');
+
+	if (typeof iteratorReturn === 'undefined') {
+		return completionThunk();
+	}
+
+	var completionRecord;
+	try {
+		var innerResult = Call(iteratorReturn, iterator, []);
+	} catch (e) {
+		// if we hit here, then "e" is the innerResult completion that needs re-throwing
+
+		// if the completion is of type "throw", this will throw.
+		completionThunk();
+		completionThunk = null; // ensure it's not called twice.
+
+		// if not, then return the innerResult completion
+		throw e;
+	}
+	completionRecord = completionThunk(); // if innerResult worked, then throw if the completion does
+	completionThunk = null; // ensure it's not called twice.
+
+	if (Type(innerResult) !== 'Object') {
+		throw new $TypeError('iterator .return must return an object');
+	}
+
+	return completionRecord;
+};