new_contents: from __future__ import absolute_import
  
  import unittest
  from flask import Flask
  
  from .. import config
  
  app = Flask('__config_test')
  
  
  class GetFuncsTest(unittest.TestCase):
  
      def test_get_module_funcs(self):
          """Test the return value."""
          self.assertIsInstance(config._get_funcs('__main__'), dict)
  
  
  class InjectFiltersTest(unittest.TestCase):
  
      def test_inject_filters_inst(self):
          """Test the return value."""
          self.assertIsInstance(config._inject_filters(app, {}), Flask)
  
      def test_inject_filters_count(self):
          """Test the return value."""
          old = len(app.jinja_env.filters)
          config._inject_filters(app, {'foo': lambda x: x})
          new = len(app.jinja_env.filters)
          self.assertGreater(new, old)
          assert 'foo' in app.jinja_env.filters
  
  
  class ConfigFlaskFiltersTest(unittest.TestCase):
  
      def test_config_filters_inst(self):
          """Test the return value."""
          self.assertIsInstance(config.config_flask_filters(app), Flask)
  
      def test_config_filters_count(self):
          """Test the return value."""
          old = len(app.jinja_env.filters)
          config.config_flask_filters(app)
          new = len(app.jinja_env.filters)
          self.assertGreater(new, old)
  
subject: Add config tests