Initial system import

node_modules/has-proto/mutator.js

@@ -0,0 +1,33 @@
+'use strict';
+
+var result = require('./')();
+
+var test = {
+	__proto__: null,
+	foo: {}
+};
+
+var setter = require('./helpers/setDunder');
+
+/** @type {import('./mutator')} */
+module.exports = function hasMutator() {
+	if (!result) {
+		return false;
+	}
+
+	var obj = { __proto__: test };
+	// @ts-expect-error: TS errors on an inherited property for some reason
+	if (obj.foo !== test.foo) {
+		return false;
+	}
+
+	if (!setter) {
+		return false;
+	}
+
+	setter(obj, null);
+	if ('foo' in obj || 'toString' in obj) {
+		return false;
+	}
+	return true;
+};