mini_test_hack.rb

def assert_equal(*args)
  call_path = caller_locations(1, 1).first.path
  call_line = caller_locations(1, 1).first.lineno
  magic_enabled = args.length == 1

  if magic_enabled
    expected_value = args.first

    if expected_value.is_a?(String) || expected_value.is_a?(Symbol) || expected_value.is_a?(Numeric)
      formatted_value = format_value(expected_value)

      # Edit the file at call_path and call_line. Finish the test
      file = File.read(call_path).lines

      modified_line = file[call_line - 1].gsub("assert_equal ", "assert_equal #{formatted_value}, ")
      modified_line = modified_line.gsub("assert_equal(", "assert_equal(#{formatted_value}, " )
      file[call_line - 1] = modified_line
      modified_file = file.join

      File.write(call_path, modified_file)

      super(expected_value, args.first)
    end
  else
    super(*args)
  end
end

def format_value(value)
  if value.is_a?(String)
    "\"#{value}\""
  else
    value.to_s
  end
end