>> It looks like the test/indent tests are only good for null-diff >> general indentation rules. > What makes you think so? When the diff outputs differences (ie a non null-diff), how does the current test/indent distinguish expected from unexpected? If there was a test/indent/ruby.rb.expected file (for example), then I could see how it could do so: 'diff ruby.rb.expected ruby.rb.new' returns nothing.