diff --git a/src/test/resources/compile-basic-features/variables/variables-string-interpolation.css b/src/test/resources/compile-basic-features/variables/variables-string-interpolation.css
index 000d756d..10cade6e 100644
--- a/src/test/resources/compile-basic-features/variables/variables-string-interpolation.css
+++ b/src/test/resources/compile-basic-features/variables/variables-string-interpolation.css
@@ -29,6 +29,7 @@
   sum: "15";
   named: "#008000";
   color: "#114488";
+  units: "10%";
 }
 #useUnderdefinedMixin {
   text: 'Hi DoNotForget :-)';
diff --git a/src/test/resources/compile-basic-features/variables/variables-string-interpolation.less b/src/test/resources/compile-basic-features/variables/variables-string-interpolation.less
index c9bd211b..28a122cd 100644
--- a/src/test/resources/compile-basic-features/variables/variables-string-interpolation.less
+++ b/src/test/resources/compile-basic-features/variables/variables-string-interpolation.less
@@ -49,6 +49,8 @@
   named: "@{namedColor}";
   @color: #114488; 
   color: "@{color}";
+  @units: 10%; 
+  units: "@{units}";
 }
 
 .underdefinedMixin() {