You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: assertions.rb
    path of file: ./repos/truffleruby/test/mri/tests/lib/test/unit
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
require 'pp'

module Test
  module Unit
    module Assertions

      ##
      # Returns the diff command to use in #diff. Tries to intelligently
      # figure out what diff to use.

      def self.diff
        unless defined? @diff
          exe = RbConfig::CONFIG['EXEEXT']
          @diff = %W"gdiff#{ex
    
      def assert_equal(exp, act, msg = nil)
        msg = message(msg) {
          exp_str = mu_pp(exp)
          act_str = mu_pp(act)
          exp_comment = ''
          act_comment = ''
          if exp_str == act_str
            if (exp.is_a?(String) && act.is_a?(String)) ||
               (exp.is_a?(Regexp) && act.is_a?(Regexp))
              exp_comment = " (#{exp.encoding})"
              act_comment = " (#{act.encoding})"
            elsif exp.is_a?(Float) && act.is_a?(Float)
              exp_str = "%\#.#{Float::DIG+2}g" % exp
              act_str = "%\#.#{Float::DIG+2}g" % act
            elsif exp.is_a?(Time) && act.is_a?(Time)
              if exp.subsec * 1000_000_000 == exp.nsec
                exp_comment = " (#{exp.nsec}[ns])"
              else
                exp_comment = " (subsec=#{exp.subsec})"
              end