Add working DEBUG and DEBUG_RESOLVER modes

lib/bundler/resolver.rb

@@ -63,15 +63,19 @@ def initialize(index, source_requirements)
     end
 
     def debug
-      puts yield if defined?($debug) && $debug
+      if ENV['DEBUG_RESOLVER']
+        debug_info = yield
+        debug_info = debug_info.inpsect unless debug_info.is_a?(String)
+        $stderr.puts debug_info
+      end
     end
 
     def resolve(reqs, activated)
       # If the requirements are empty, then we are in a success state. Aka, all
       # gem dependencies have been resolved.
       throw :success, activated if reqs.empty?
 
-      debug { STDIN.gets ; print "\e[2J\e[f" ; "==== Iterating ====\n\n" }
+      debug { print "\e[2J\e[f" ; "==== Iterating ====\n\n" }
 
       # Sort dependencies so that the ones that are easiest to resolve are first.
       # Easiest to resolve is defined by:

lib/bundler/ui.rb

@@ -17,8 +17,8 @@ def initialize(shell)
         @shell = shell
       end
 
-      # TODO: Add debug mode
       def debug(msg)
+        @shell.say(msg) if ENV['DEBUG']
       end
 
       def info(msg)