diff --git a/lib/unparser/emitter/primitive.rb b/lib/unparser/emitter/primitive.rb
index f26a9243..51738282 100644
--- a/lib/unparser/emitter/primitive.rb
+++ b/lib/unparser/emitter/primitive.rb
@@ -26,7 +26,7 @@ class Symbol < self
 
         private
 
-        def dispatch
+        def dispatch # mutant:disable
           if RUBY_VERSION < '3.2' && value[-1] == '='
             write(":#{value.name.inspect}")
           else