diff --git a/lib/test/unit.rb b/lib/test/unit.rb
index c44fbf8688..c64d9b488d 100644
--- a/lib/test/unit.rb
+++ b/lib/test/unit.rb
@@ -671,7 +671,8 @@ module Test
         when :always
           color = true
         when :auto, nil
-          color = @options[:job_status] == :replace && /mswin|mingw/ !~ RUBY_PLATFORM && /dumb/ !~ ENV["TERM"]
+          color = @options[:job_status] == :replace && /dumb/ !~ ENV["TERM"]
+          color &&= /mswin|mingw/ !~ RUBY_PLATFORM
         else
           color = false
         end