From 10e2f0f37b24e59c20e18b4067e0f7efb6033621 Mon Sep 17 00:00:00 2001
From: Yarchik <spoko.dev@gmail.com>
Date: Wed, 17 Jun 2026 14:53:49 +0100
Subject: [PATCH] fix: do not reuse the opening `*` when closing a comment
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`indexOf("*/", pos)` started searching at the opening `/`, so the `*` of
the opening `/*` could be matched as the `*` of a closing `*/`. As a
result `/*/` was parsed as a closed, empty comment instead of an unclosed
comment whose content is `/`, and stringifying it produced `/**/` —
breaking the lossless round-trip (`/*/` is also a known CSS comment hack).

Start the search past the opening delimiter (`pos + 2`).
---
 lib/parse.js  |  2 +-
 test/index.js |  3 +++
 test/parse.js | 13 +++++++++++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/lib/parse.js b/lib/parse.js
index 7d343ca..48d2981 100644
--- a/lib/parse.js
+++ b/lib/parse.js
@@ -103,7 +103,7 @@ module.exports = function (input) {
 
       // Comments
     } else if (code === slash && value.charCodeAt(pos + 1) === star) {
-      next = value.indexOf("*/", pos);
+      next = value.indexOf("*/", pos + 2);
 
       token = {
         type: "comment",
diff --git a/test/index.js b/test/index.js
index 2131248..91c10b3 100644
--- a/test/index.js
+++ b/test/index.js
@@ -7,6 +7,9 @@ describe("ValueParser", () => {
     const tests = [
       " rgba( 34 , 45 , 54, .5 ) ",
       "w1 w2 w6 \n f(4) ( ) () \t \"s't\" 'st\\\"2'",
+      "/*/",
+      "a /*/ b",
+      "/*/ comment hack /**/",
     ];
 
     tests.forEach((item) => {
diff --git a/test/parse.js b/test/parse.js
index 22aa393..1ac8a39 100644
--- a/test/parse.js
+++ b/test/parse.js
@@ -1683,6 +1683,19 @@ const tests = [
       { type: "word", sourceIndex: 0, sourceEndIndex: 3, value: "U+Z" },
     ],
   },
+  {
+    message: "should not reuse the opening star to close a comment",
+    fixture: "/*/",
+    expected: [
+      {
+        type: "comment",
+        sourceIndex: 0,
+        sourceEndIndex: 3,
+        value: "/",
+        unclosed: true,
+      },
+    ],
+  },
 ];
 
 describe("Parse", () => {