When rubygems/test_case is required the default user interaction is a MockGemUi.
Module that defines the default UserInteraction.  Any class including this module will have access to the ui method that returns the default UI.
Return the default UI.
 
               # File rubygems/user_interaction.rb, line 28
def self.ui
  @ui ||= Gem::ConsoleUI.new
end
             
            Set the default UI.  If the default UI is never explicitly set, a simple console based UserInteraction will be used automatically.
 
               # File rubygems/user_interaction.rb, line 36
def self.ui=(new_ui)
  @ui = new_ui
end
             
            See DefaultUserInteraction::ui
 
               # File rubygems/user_interaction.rb, line 54
def ui
  Gem::DefaultUserInteraction.ui
end
             
            See DefaultUserInteraction::ui=
 
               # File rubygems/user_interaction.rb, line 61
def ui=(new_ui)
  Gem::DefaultUserInteraction.ui = new_ui
end
             
            See DefaultUserInteraction::use_ui
 
               # File rubygems/user_interaction.rb, line 68
def use_ui(new_ui, &block)
  Gem::DefaultUserInteraction.use_ui(new_ui, &block)
end