# File lib/mocha/expectation_error.rb, line 7
 7:     def initialize(message = nil, backtrace = [], lib_directory = LIB_DIRECTORY)
 8:       super(message)
 9:       filtered_backtrace = backtrace.reject { |location| Regexp.new(lib_directory).match(File.expand_path(location)) }
10:       set_backtrace(filtered_backtrace)
11:     end