build

node_modules/es-abstract/helpers/DefineOwnProperty.js

@@ -0,0 +1,45 @@
+'use strict';
+
+var GetIntrinsic = require('../GetIntrinsic');
+
+var $defineProperty = GetIntrinsic('%Object.defineProperty%', true);
+
+if ($defineProperty) {
+	try {
+		$defineProperty({}, 'a', { value: 1 });
+	} catch (e) {
+		// IE 8 has a broken defineProperty
+		$defineProperty = null;
+	}
+}
+
+var callBound = require('../helpers/callBound');
+
+var $isEnumerable = callBound('Object.prototype.propertyIsEnumerable');
+
+// eslint-disable-next-line max-params
+module.exports = function DefineOwnProperty(IsDataDescriptor, SameValue, FromPropertyDescriptor, O, P, desc) {
+	if (!$defineProperty) {
+		if (!IsDataDescriptor(desc)) {
+			// ES3 does not support getters/setters
+			return false;
+		}
+		if (!desc['[[Configurable]]'] || !desc['[[Writable]]']) {
+			return false;
+		}
+
+		// fallback for ES3
+		if (P in O && $isEnumerable(O, P) !== !!desc['[[Enumerable]]']) {
+			// a non-enumerable existing property
+			return false;
+		}
+
+		// property does not exist at all, or exists but is enumerable
+		var V = desc['[[Value]]'];
+		// eslint-disable-next-line no-param-reassign
+		O[P] = V; // will use [[Define]]
+		return SameValue(O[P], V);
+	}
+	$defineProperty(O, P, FromPropertyDescriptor(desc));
+	return true;
+};