From 33ffe9cb9ae8c5a285102befd46ef76ba7feaee0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Iiro=20Ja=CC=88ppinen?= <iiro@jappinen.fi>
Date: Sat, 24 Jul 2021 11:07:14 +0300
Subject: [PATCH] fix: do not match braces when they start with the dollar sign
 (`$`)

---
 lib/validateConfig.js       | 5 +++--
 test/validateConfig.spec.js | 4 ++++
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/lib/validateConfig.js b/lib/validateConfig.js
index bcc79091c..6e5011ff4 100644
--- a/lib/validateConfig.js
+++ b/lib/validateConfig.js
@@ -23,13 +23,14 @@ const TEST_DEPRECATED_KEYS = new Map([
  * two curly braces without a `,` or `..` between them, to make sure
  * users can still accidentally use them without
  * some linters never matching anything. It will further not match
- * escaped braces `\{` `\}`, or if braces contain an escaped comma `\,`
+ * escaped braces `\{` `\}`, or if braces contain an escaped comma `\,`.
+ * Finally, a dollar sign `${` inhibits brace expansion.
  *
  * For example `.{js,ts}` or `file_{1..10}` are valid but `*.{js}` is not.
  *
  * @see https://www.gnu.org/software/bash/manual/html_node/Brace-Expansion.html
  */
-const BRACES_REGEXP = new RegExp(/(?<!\\)({)(?:(?!(?<!\\),|\.\.).)*?(?<!\\)(})/g)
+const BRACES_REGEXP = new RegExp(/(?<![\\$])({)(?:(?!(?<!\\),|\.\.).)*?(?<!\\)(})/g)
 
 /**
  * Remove braces from incorrect glob patterns.
diff --git a/test/validateConfig.spec.js b/test/validateConfig.spec.js
index 8937668e1..2e8946e95 100644
--- a/test/validateConfig.spec.js
+++ b/test/validateConfig.spec.js
@@ -19,6 +19,10 @@ describe('BRACES_REGEXP', () => {
     expect('*.{js\\,ts}'.match(BRACES_REGEXP)).toBeTruthy()
   })
 
+  it("should not match '*.${js}'", () => {
+    expect('*.${js}'.match(BRACES_REGEXP)).not.toBeTruthy()
+  })
+
   it(`should not match '.{js,ts}'`, () => {
     expect('.{js,ts}'.match(BRACES_REGEXP)).not.toBeTruthy()
   })