npm and error messages

node_modules/es6-set/test/ext/get-first.js

@@ -0,0 +1,12 @@
+'use strict';
+
+var Set     = require('../../');
+
+module.exports = function (t, a) {
+	var content = ['raz', 2, true], set = new Set(content);
+
+	a(t.call(set), 'raz');
+
+	set = new Set();
+	a(t.call(set), undefined);
+};