old_contents: import docker
  
  from webcomix.docker import DockerManager
  
  def test_no_javascript_spawns_no_container():
      manager = DockerManager(False)
      manager.__enter__()
      manager.client = docker.from_env()
      assert manager._get_container() is None
  
  def test_javascript_spawns_container():
      manager = DockerManager(True)
      manager.__enter__()
      assert manager._get_container() is not None
      manager.__exit__(None, None, None)
  
  def test_javascript_exit_removes_container():
      manager = DockerManager(True)
      manager.__enter__()
      manager.__exit__(None, None, None)
      assert manager._get_container() is None
  
new_contents: import docker
  import pytest
  
  from webcomix.docker import DockerManager, CONTAINER_NAME
  
  @pytest.fixture
  def cleanup_container(test):
      yield None
      client = docker.from_env()
      for container in client.containers().list():
          if container.attrs["Config"]["Image"] == CONTAINER_NAME:
              container.kill()
  
  def test_no_javascript_spawns_no_container(cleanup_container):
      manager = DockerManager(False)
      manager.__enter__()
      manager.client = docker.from_env()
      assert manager._get_container() is None
  
  def test_javascript_spawns_container(cleanup_container):
      manager = DockerManager(True)
      manager.__enter__()
      assert manager._get_container() is not None
      manager.__exit__(None, None, None)
  
  def test_javascript_exit_removes_container(cleanup_container):
      manager = DockerManager(True)
      manager.__enter__()
      manager.__exit__(None, None, None)
      assert manager._get_container() is None
  
subject: Add test fixture for docker tests