diff --git a/Library/Homebrew/dev-cmd/man.rb b/Library/Homebrew/dev-cmd/man.rb
index 8d55043393..147a34ef9a 100644
--- a/Library/Homebrew/dev-cmd/man.rb
+++ b/Library/Homebrew/dev-cmd/man.rb
@@ -125,7 +125,7 @@ module Homebrew
       ronn.write markup
       ronn.close_write
       ronn_output = ronn.read
-      odie "Got no output from ronn!" unless ronn_output
+      odie "Got no output from ronn!" if ronn_output.blank?
       if format_flag == "--markdown"
         ronn_output = ronn_output.gsub(%r{<var>(.*?)</var>}, "*`\\1`*")
                                  .gsub(/\n\n\n+/, "\n\n")