I usually disable RubyMine inspections when I coding in road without power source connection. I noticed Problems with autocompletion when all inspections are disabled:

# plist_parser.rb
class PlistParser
end

# snippet_parser.rb
require File.expand_path(File.dirname(__FILE__) + '/plist_parser')
class SnippetParser < Pli<caret> # completion doesn't show PlistParser
end

P.S: After I enabled inspection - all was ok

Environment: RubyMine 1.1 release

Issue was closed