This method is only available on newer versions.
The first available version (v2_6_3) is shown here.
debug?()
public
Whether or not debug
messages should be printed. By default, whether or not the
`MOLINILLO_DEBUG` environment variable is set.
@return [Boolean]
# File lib/bundler/vendor/molinillo/lib/molinillo/modules/ui.rb, line 62
def debug?
return @debug_mode if defined?(@debug_mode)
@debug_mode = ENV['MOLINILLO_DEBUG']
end