Move to test concrete class over abstract class (#10243)

tests/unit/README.md

@@ -1,6 +1,5 @@
 # Unit test README
 
-## test_contracts_graph_parsed.py
 
 ### The Why
 We need to ensure that we can go from objects to dictionaries and back without any
@@ -16,3 +15,7 @@ versions of the object we're interested in testing, and run the different genera
 of the object through the test. This gives us confidence that for any allowable configuration
 of an object, state is not changed when moving back and forth betweeen the python object
 version and the seralized version.
+
+### The What
+
+- We test concrete classes in the codebase and do not test abstract classes as they are implementation details. [reference](https://enterprisecraftsmanship.com/posts/how-to-unit-test-an-abstract-class/)

tests/unit/task/test_clone.py

@@ -0,0 +1,16 @@
+from unittest.mock import MagicMock, patch
+
+from dbt.flags import get_flags
+from dbt.task.clone import CloneTask
+
+
+def test_clone_task_not_preserve_edges():
+    mock_node_selector = MagicMock()
+    mock_spec = MagicMock()
+    with patch.object(
+        CloneTask, "get_node_selector", return_value=mock_node_selector
+    ), patch.object(CloneTask, "get_selection_spec", return_value=mock_spec):
+        task = CloneTask(get_flags(), None, None)
+        task.get_graph_queue()
+        # when we get the graph queue, preserve_edges is False
+        mock_node_selector.get_graph_queue.assert_called_with(mock_spec, False)

tests/unit/task/test_run.py

@@ -0,0 +1,52 @@
+from argparse import Namespace
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from dbt.config.runtime import RuntimeConfig
+from dbt.flags import get_flags, set_from_args
+from dbt.task.run import RunTask
+from dbt.tests.util import safe_set_invocation_context
+
+
+@pytest.mark.parametrize(
+    "exception_to_raise, expected_cancel_connections",
+    [
+        (SystemExit, True),
+        (KeyboardInterrupt, True),
+        (Exception, False),
+    ],
+)
+def test_run_task_cancel_connections(
+    exception_to_raise, expected_cancel_connections, runtime_config: RuntimeConfig
+):
+    safe_set_invocation_context()
+
+    def mock_run_queue(*args, **kwargs):
+        raise exception_to_raise("Test exception")
+
+    with patch.object(RunTask, "run_queue", mock_run_queue), patch.object(
+        RunTask, "_cancel_connections"
+    ) as mock_cancel_connections:
+
+        set_from_args(Namespace(write_json=False), None)
+        task = RunTask(
+            get_flags(),
+            runtime_config,
+            None,
+        )
+        with pytest.raises(exception_to_raise):
+            task.execute_nodes()
+        assert mock_cancel_connections.called == expected_cancel_connections
+
+
+def test_run_task_preserve_edges():
+    mock_node_selector = MagicMock()
+    mock_spec = MagicMock()
+    with patch.object(RunTask, "get_node_selector", return_value=mock_node_selector), patch.object(
+        RunTask, "get_selection_spec", return_value=mock_spec
+    ):
+        task = RunTask(get_flags(), None, None)
+        task.get_graph_queue()
+        # when we get the graph queue, preserve_edges is True
+        mock_node_selector.get_graph_queue.assert_called_with(mock_spec, True)