fix(styles): prevent utility API from creating unwanted classes

packages/styles/src/functions/_string.scss

@@ -1,12 +1,17 @@
 @use 'sass:string';
 
-@function replace($string, $term, $replacement: '') {
+@function contains($string, $term) {
+  $index: string.index($string, $term);
+  @return if($index == null, false, true);
+}
+
+@function replace($string, $term, $replacement) {
   $index: string.index($string, $term);
 
   @if $index {
     $before: string.slice($string, 1, $index - 1);
     $after: string.slice($string, $index + string.length($term));
-    @return $before + $replacement + replace($after, $term, $replacement);
+    @return $before + $replacement + $after;
   }
 
   @return $string;

packages/styles/src/utilities/index.scss

@@ -16,13 +16,15 @@
     $prefixes: map.get($classesConfig, prefixes);
 
     @each $key, $value in $tokens {
-      $suffix: string.replace($key, 'post-utility-#{$group}');
+      @if (string.contains($key, 'post-utility-#{$group}')) {
+        $suffix: string.replace($key, 'post-utility-#{$group}', '');
 
-      @each $prefix, $properties in $prefixes {
-        @if $responsive {
-          @include generate-responsive-utilities($properties, $value, $prefix, $suffix);
-        } @else {
-          @include generate-utilities($properties, $value, $prefix, $suffix);
+        @each $prefix, $properties in $prefixes {
+          @if $responsive {
+            @include generate-responsive-utilities($properties, $value, $prefix, $suffix);
+          } @else {
+            @include generate-utilities($properties, $value, $prefix, $suffix);
+          }
         }
       }
     }

packages/styles/tests/functions/string.test.scss

@@ -3,6 +3,18 @@
 
 $paragraph: "I think Ruth's dog is cuter than your dog!";
 
+// it should return true if the term is found
+@include jest.equal(
+    true,
+    string.contains($paragraph, 'dog')
+);
+
+// it should return false if the term is not found
+@include jest.equal(
+    false,
+    string.contains($paragraph, 'cat')
+);
+
 // it should replace a term by another
 @include jest.equal(
     'I think my dog is cuter than your dog!',