old_contents: 
  import unittest
  
  from redsugar.utils import RedLexer
  
  
  class TestRedLexer(unittest.TestCase):
  
      def setUp(self):
          self.source_code = """fn hello
  print "hello world"
  end
          """
          self.lexer = RedLexer(self.source_code)
  
      def tearDown(self):
          pass
  
      def test_tokenize(self):
          self.lexer.tokenize()
          self.assertEqual(self.lexer.tokens[0], '\n')
          self.assertEqual(self.lexer.tokens[2], 'fn')
  
      def test_remove_empty_tokens(self):
          self.assertNotIn('', self.lexer.tokens)
  
      def test_remove_newlines(self):
          self.assertNotIn('\n', self.lexer.tokens)
  
new_contents: 
  import unittest
  
  from redsugar.utils import RedLexer
  
  TESTING_SOURCE_CODE = """
  fn hello
      print "hello world"
  end
  """
  
  
  class TestRedLexer(unittest.TestCase):
  
      def setUp(self):
          self.source_code = TESTING_SOURCE_CODE
          self.lexer = RedLexer(self.source_code)
          self.lexer.tokenize()
  
      def tearDown(self):
          pass
  
      def test_tokenize_makes_list(self):
          self.assertIs(list, type(self.lexer.tokens))
  
      def test_tokenize_removes_newlines(self):
          for item in self.lexer.tokens:
              self.assertNotIn('\n', item)
  
      def test_tokenize_content_is_as_expected(self):
          self.assertEqual(self.lexer.tokens[0], 'fn')
          self.assertEqual(self.lexer.tokens[1], 'hello')
          self.assertEqual(self.lexer.tokens[2], 'print')
          self.assertEqual(
              self.lexer.tokens[3],
              '"',
              "first single quote not alone"
          )
          self.assertEqual(self.lexer.tokens[4], "hello")
          self.assertEqual(
              self.lexer.tokens[3],
              '"',
              "second single quote not alone"
          )
          self.assertEqual(self.lexer.tokens[2], 'end')
  
      def test_remove_empty_tokens(self):
          self.assertNotIn('', self.lexer.tokens)
  
subject: split tests up to specific functionality