Add tests for run CLI command

tests/cli/test_main.py

@@ -1,4 +1,8 @@
+from pathlib import Path
+from unittest.mock import MagicMock
+
 import anycastd
+import pytest
 
 
 def test_version_displayed_correctly(anycastd_cli):
@@ -9,3 +13,52 @@ def test_version_displayed_correctly(anycastd_cli):
 
     assert result.exit_code == 0
     assert result.stdout == expected
+
+
+class TestRunCMD:
+    """Test the run command."""
+
+    @pytest.fixture
+    def mock_configuration(self, mocker):
+        """An autospecced mock instance of the MainConfiguration class."""
+        return mocker.create_autospec(
+            "anycastd._configuration.MainConfiguration", spec_set=True, instance=True
+        )
+
+    @pytest.fixture
+    def mock_run_from_configuration(self, mocker) -> MagicMock:
+        """An autospecced mock of the run_from_configuration function."""
+        return mocker.patch("anycastd._cli.main.run_from_configuration", autospec=True)
+
+    @pytest.fixture
+    def mock_get_main_configuration(self, mocker, mock_configuration) -> MagicMock:
+        """An autospecced mock of the _get_main_configuration function."""
+        mock = mocker.patch("anycastd._cli.main._get_main_configuration", autospec=True)
+        mock.return_value = mock_configuration
+        return mock
+
+    def test_calls_get_main_configuration_w_config_path(
+        self, anycastd_cli, mock_get_main_configuration, mock_run_from_configuration
+    ):
+        """_get_main_configuration is called with the config path."""
+        config = Path("/path/to/config.toml")
+
+        anycastd_cli("run", "--config", config.as_posix())
+
+        mock_get_main_configuration.assert_called_once_with(config)
+
+    def test_calls_run_from_configuration(
+        self,
+        anycastd_cli,
+        mock_configuration,
+        mock_run_from_configuration,
+        mock_get_main_configuration,
+    ):
+        """run_from_configuration is called.
+
+        Run from configuration is called with the main configuration object
+        obtained from the configuration file path.
+        """
+        anycastd_cli("run")
+
+        mock_run_from_configuration.assert_called_once_with(mock_configuration)