Improve code quality and write tests

node_modules/regexp-tree/dist/compat-transpiler/transforms/compat-x-flag-transform.js

@@ -0,0 +1,23 @@
+/**
+ * The MIT License (MIT)
+ * Copyright (c) 2017-present Dmitry Soshnikov <dmitry.soshnikov@gmail.com>
+ */
+
+'use strict';
+
+/**
+ * A regexp-tree plugin to remove `x` flag `/foo/x` to `/foo/`.
+ *
+ * Note: other features of `x` flags (whitespace, comments) are
+ * already removed at parsing stage.
+ */
+
+module.exports = {
+  RegExp: function RegExp(_ref) {
+    var node = _ref.node;
+
+    if (node.flags.includes('x')) {
+      node.flags = node.flags.replace('x', '');
+    }
+  }
+};