RubyMine can't do code completion in block

I'm writing an application that use the mechanize gem.  When I first create a Mechanize instance, then call methods on it, RubyMine can suggesting method names as you can see in the following snapshot.

However, if I use the block style to write the same code, RubyMine can't correctly do code completion. 

I hope you guys can fix this problem. Thank you!