From a141d0ac938edcbab63fc9b75b43f441f5ff2f68 Mon Sep 17 00:00:00 2001
From: Daniel Puckowski <puckowski.d@gmail.com>
Date: Wed, 27 Nov 2024 17:51:40 -0500
Subject: [PATCH] fix(issue:4258) variable interpolation after math

* Fixes variable interpolation issue after previous variable addition.
---
 packages/less/src/less/parser/parser.js      |  4 +++-
 packages/test-data/css/_main/variables.css   |  3 +++
 packages/test-data/less/_main/variables.less | 11 +++++++++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/packages/less/src/less/parser/parser.js b/packages/less/src/less/parser/parser.js
index 59aa2eef4..fd560512b 100644
--- a/packages/less/src/less/parser/parser.js
+++ b/packages/less/src/less/parser/parser.js
@@ -1707,7 +1707,9 @@ const Parser = function Parser(context, imports, fileInfo, currentIndex) {
                             }
                             // Treat like quoted values, but replace vars like unquoted expressions
                             const quote = new tree.Quoted('\'', item, true, index, fileInfo);
-                            quote.variableRegex = /@([\w-]+)/g;
+                            if (!item.startsWith('@{')) {
+                                quote.variableRegex = /@([\w-]+)/g;
+                            }
                             quote.propRegex = /\$([\w-]+)/g;
                             result.push(quote);
                         }
diff --git a/packages/test-data/css/_main/variables.css b/packages/test-data/css/_main/variables.css
index fa03b1eb7..b1ac96569 100644
--- a/packages/test-data/css/_main/variables.css
+++ b/packages/test-data/css/_main/variables.css
@@ -69,3 +69,6 @@
   mul-px-2: 140px;
   mul-px-3: 140px;
 }
+.radio_checked {
+  border-color: #fff;
+}
diff --git a/packages/test-data/less/_main/variables.less b/packages/test-data/less/_main/variables.less
index ae8c9be45..6ef921826 100644
--- a/packages/test-data/less/_main/variables.less
+++ b/packages/test-data/less/_main/variables.less
@@ -125,3 +125,14 @@
     mul-px-3: ((@px * 1) * @cm);
   }
 }
+
+@a1: 1px;
+@b2: 2px;
+@c3: @a1 + @b2;
+
+@radio-cls: radio;
+@radio-cls-checked: @{radio-cls}_checked;
+
+.@{radio-cls-checked} {
+  border-color: #fff;
+}