From 2e7bea4a6abdea0d99c70bbb28b4889df58223d4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Hu=C3=A1ng=20J=C3=B9nli=C3=A0ng?= <i@jhuang.me>
Date: Thu, 5 Sep 2019 11:35:57 -0400
Subject: [PATCH] fix: transform name capturing regex once (#10395)

* fix: transform name capturing regex once

* refactor: early return when pattern contains only lookbehind

* chore: simplify test regex

* chore: run test on >=8.0.0
---
 .../src/index.js                                           | 2 +-
 .../test/fixtures/runtime/issue-10393/exec.js              | 7 +++++++
 .../test/fixtures/runtime/issue-10393/options.json         | 3 +++
 3 files changed, 11 insertions(+), 1 deletion(-)
 create mode 100644 packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/exec.js
 create mode 100644 packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/options.json

diff --git a/packages/babel-plugin-transform-named-capturing-groups-regex/src/index.js b/packages/babel-plugin-transform-named-capturing-groups-regex/src/index.js
index 042d16de9d4d..d646101852e0 100644
--- a/packages/babel-plugin-transform-named-capturing-groups-regex/src/index.js
+++ b/packages/babel-plugin-transform-named-capturing-groups-regex/src/index.js
@@ -12,7 +12,7 @@ export default function({ types: t }, options) {
     visitor: {
       RegExpLiteral(path) {
         const node = path.node;
-        if (node.pattern.indexOf("(?<") === -1) {
+        if (!/\(\?<(?![=!])/.test(node.pattern)) {
           // Return early if there are no named groups.
           // The .indexOf check may have false positives (e.g. /\(?</); in
           // this case we parse the regex and regexp-tree won't transform it.
diff --git a/packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/exec.js b/packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/exec.js
new file mode 100644
index 000000000000..e12e576b6b0c
--- /dev/null
+++ b/packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/exec.js
@@ -0,0 +1,7 @@
+const regex = /(?<=a)(?<a>[a])/
+
+const result = regex.exec("aa");
+
+expect(result.groups).toEqual({
+  a: "a"
+});
diff --git a/packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/options.json b/packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/options.json
new file mode 100644
index 000000000000..2454c2169cf8
--- /dev/null
+++ b/packages/babel-plugin-transform-named-capturing-groups-regex/test/fixtures/runtime/issue-10393/options.json
@@ -0,0 +1,3 @@
+{
+  "minNodeVersion": "8.0.0"
+}