1 files changed, 53 insertions, 0 deletions
diff --git a/node_modules/babel-plugin-transform-regexp-constructors/lib/index.js b/node_modules/babel-plugin-transform-regexp-constructors/lib/index.js
new file mode 100644
index 00000000..be79d8df
--- /dev/null
+++ b/node_modules/babel-plugin-transform-regexp-constructors/lib/index.js
@@ -0,0 +1,53 @@
+"use strict";
+
+function createRegExpLiteral(args, prettify, t) {
+  const evaluatedArgs = args.map(a => a.evaluate());
+
+  if (!evaluatedArgs.every(a => a.confident && typeof a.value === "string")) {
+    return;
+  }
+
+  let pattern = evaluatedArgs.length >= 1 && evaluatedArgs[0].value !== "" ? evaluatedArgs[0].value : "(?:)";
+  const flags = evaluatedArgs.length >= 2 ? evaluatedArgs[1].value : "";
+  pattern = new RegExp(pattern).source;
+
+  if (prettify) {
+    pattern = pattern.replace(/\n/g, "\\n").replace(/\u2028/g, "\\u2028").replace(/\u2029/g, "\\u2029").replace(/[\b]/g, "[\\b]").replace(/\v/g, "\\v").replace(/\f/g, "\\f").replace(/\r/g, "\\r");
+  }
+
+  pattern = pattern.replace(/\0/g, "\\0");
+  return t.regExpLiteral(pattern, flags);
+}
+
+function maybeReplaceWithRegExpLiteral(path, t) {
+  if (!t.isIdentifier(path.node.callee, {
+    name: "RegExp"
+  })) {
+    return;
+  }
+
+  const regExpLiteral = createRegExpLiteral(path.get("arguments"), true, t);
+
+  if (regExpLiteral) {
+    path.replaceWith(regExpLiteral);
+  }
+}
+
+module.exports = function ({
+  types: t
+}) {
+  return {
+    name: "transform-regexp-constructors",
+    visitor: {
+      NewExpression(path) {
+        maybeReplaceWithRegExpLiteral(path, t);
+      },
+
+      CallExpression(path) {
+        // equivalent to `new RegExp()` according to §21.2.3
+        maybeReplaceWithRegExpLiteral(path, t);
+      }
+
+    }
+  };
+};
+\ No newline at end of file