Fix tests/models/test_taskinstance.py for Database Isolation Tests (#41344)

Author: jscheffl

airflow/models/taskinstance.py

@@ -1404,6 +1404,25 @@ def _get_previous_execution_date(
     return pendulum.instance(prev_ti.execution_date) if prev_ti and prev_ti.execution_date else None
 
 
+def _get_previous_start_date(
+    *,
+    task_instance: TaskInstance | TaskInstancePydantic,
+    state: DagRunState | None,
+    session: Session,
+) -> pendulum.DateTime | None:
+    """
+    Return the start date from property previous_ti_success.
+
+    :param task_instance: the task instance
+    :param state: If passed, it only take into account instances of a specific state.
+    :param session: SQLAlchemy ORM Session
+    """
+    log.debug("previous_start_date was called")
+    prev_ti = task_instance.get_previous_ti(state=state, session=session)
+    # prev_ti may not exist and prev_ti.start_date may be None.
+    return pendulum.instance(prev_ti.start_date) if prev_ti and prev_ti.start_date else None
+
+
 def _email_alert(
     *, task_instance: TaskInstance | TaskInstancePydantic, exception, task: BaseOperator
 ) -> None:
@@ -2533,10 +2552,7 @@ def get_previous_start_date(
         :param state: If passed, it only take into account instances of a specific state.
         :param session: SQLAlchemy ORM Session
         """
-        self.log.debug("previous_start_date was called")
-        prev_ti = self.get_previous_ti(state=state, session=session)
-        # prev_ti may not exist and prev_ti.start_date may be None.
-        return pendulum.instance(prev_ti.start_date) if prev_ti and prev_ti.start_date else None
+        return _get_previous_start_date(task_instance=self, state=state, session=session)
 
     @property
     def previous_start_date_success(self) -> pendulum.DateTime | None:

airflow/serialization/pydantic/taskinstance.py

@@ -381,6 +381,21 @@ def get_previous_execution_date(
 
         return _get_previous_execution_date(task_instance=self, state=state, session=session)
 
+    def get_previous_start_date(
+        self,
+        state: DagRunState | None = None,
+        session: Session | None = None,
+    ) -> pendulum.DateTime | None:
+        """
+        Return the execution date from property previous_ti_success.
+
+        :param state: If passed, it only take into account instances of a specific state.
+        :param session: SQLAlchemy ORM Session
+        """
+        from airflow.models.taskinstance import _get_previous_start_date
+
+        return _get_previous_start_date(task_instance=self, state=state, session=session)
+
     def email_alert(self, exception, task: BaseOperator) -> None:
         """
         Send alert email with exception information.

tests/conftest.py

@@ -1082,6 +1082,7 @@ def create_task_instance(dag_maker, create_dummy_dag):
 
     Uses ``create_dummy_dag`` to create the dag structure.
     """
+    from airflow.operators.empty import EmptyOperator
 
     def maker(
         execution_date=None,
@@ -1091,14 +1092,46 @@ def maker(
         run_type=None,
         data_interval=None,
         external_executor_id=None,
+        dag_id="dag",
+        task_id="op1",
+        task_display_name=None,
+        max_active_tis_per_dag=16,
+        max_active_tis_per_dagrun=None,
+        pool="default_pool",
+        executor_config=None,
+        trigger_rule="all_done",
+        on_success_callback=None,
+        on_execute_callback=None,
+        on_failure_callback=None,
+        on_retry_callback=None,
+        email=None,
         map_index=-1,
         **kwargs,
     ) -> TaskInstance:
         if execution_date is None:
             from airflow.utils import timezone
 
             execution_date = timezone.utcnow()
-        _, task = create_dummy_dag(with_dagrun_type=None, **kwargs)
+        with dag_maker(dag_id, **kwargs):
+            op_kwargs = {}
+            from tests.test_utils.compat import AIRFLOW_V_2_9_PLUS
+
+            if AIRFLOW_V_2_9_PLUS:
+                op_kwargs["task_display_name"] = task_display_name
+            task = EmptyOperator(
+                task_id=task_id,
+                max_active_tis_per_dag=max_active_tis_per_dag,
+                max_active_tis_per_dagrun=max_active_tis_per_dagrun,
+                executor_config=executor_config or {},
+                on_success_callback=on_success_callback,
+                on_execute_callback=on_execute_callback,
+                on_failure_callback=on_failure_callback,
+                on_retry_callback=on_retry_callback,
+                email=email,
+                pool=pool,
+                trigger_rule=trigger_rule,
+                **op_kwargs,
+            )
 
         dagrun_kwargs = {"execution_date": execution_date, "state": dagrun_state}
         if run_id is not None: