def test_override_existing_version(self):
        fake_path_class = MagicMock(spec=Path)
        fake_path = fake_path_class.return_value
        fake_path.read_text.return_value = '[tool.poetry]\nversion = "1.2.3"'

        cmd = VersionCommand(pyproject_toml_path=fake_path)
        cmd.update_pyproject_version('20.04dev1')

        text = fake_path.write_text.call_args[0][0]

        toml = tomlkit.parse(text)

        self.assertEqual(toml['tool']['poetry']['version'], '20.4.dev1')
    def test_empty_tool_section(self):
        fake_path_class = MagicMock(spec=Path)
        fake_path = fake_path_class.return_value
        fake_path.read_text.return_value = "[tool]"

        cmd = VersionCommand(pyproject_toml_path=fake_path)
        cmd.update_pyproject_version('20.04dev1')

        text = fake_path.write_text.call_args[0][0]

        toml = tomlkit.parse(text)

        self.assertEqual(toml['tool']['poetry']['version'], '20.4.dev1')