Fix TaskSDK unit test config file path handling for installed packages and monorepo

[jason810496]

Why

When using breeze shell --use-airflow-version owner:repo/branch --mount-sources providers-and-tests and run pytest directly in the shell, I encounter the following error:

ERROR providers/standard/tests/unit/standard/operators/test_trigger_dagrun.py - FileNotFoundError: [Errno 2] No such file or directory: '/usr/python/lib/airflow-core/src/airflow/config_templates/unit_tests.cfg'

Full traceback:

============================================================================================ ERRORS ============================================================================================
___________________________________________________ ERROR collecting providers/standard/tests/unit/standard/operators/test_trigger_dagrun.py ___________________________________________________
providers/standard/tests/unit/standard/operators/test_trigger_dagrun.py:29: in <module>
    from airflow.models.dag import DagModel
/usr/python/lib/python3.10/site-packages/airflow/models/dag.py:55: in <module>
    from airflow.models.dagrun import DagRun
/usr/python/lib/python3.10/site-packages/airflow/models/dagrun.py:74: in <module>
    from airflow.sdk.definitions.deadline import DeadlineReference
/usr/python/lib/python3.10/site-packages/airflow/sdk/definitions/deadline.py:25: in <module>
    from airflow.sdk.serde import deserialize, serialize
/usr/python/lib/python3.10/site-packages/airflow/sdk/serde/__init__.py:34: in <module>
    from airflow.sdk.configuration import conf
/usr/python/lib/python3.10/site-packages/airflow/sdk/configuration.py:264: in __getattr__
    val = initialize_config()
/usr/python/lib/python3.10/site-packages/airflow/sdk/configuration.py:258: in initialize_config
    airflow_config_parser.load_test_config()
/usr/python/lib/python3.10/site-packages/airflow/sdk/configuration.py:173: in load_test_config
    unit_test_config = unit_test_config_file.read_text()
/usr/python/lib/python3.10/pathlib.py:1134: in read_text
    with self.open(mode='r', encoding=encoding, errors=errors) as f:
/usr/python/lib/python3.10/pathlib.py:1119: in open
    return self._accessor.open(self, mode, buffering, encoding, errors,
E   FileNotFoundError: [Errno 2] No such file or directory: '/usr/python/lib/airflow-core/src/airflow/config_templates/unit_tests.cfg'
=================================================================================== short test summary info ====================================================================================
ERROR providers/standard/tests/unit/standard/operators/test_trigger_dagrun.py - FileNotFoundError: [Errno 2] No such file or directory: '/usr/python/lib/airflow-core/src/airflow/config_templates/unit_tests.cfg'
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Interrupted: 1 error during collection !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
================================================================================= 1 warning, 1 error in 2.08s ==================================================================================

The SDK's load_test_config() method was using an incorrect path calculation to locate unit_tests.cfg, which only worked in the monorepo structure. When the SDK is installed as a package in site-packages, the path resolution failed because it assumed the monorepo directory structure.

What

We updated load_test_config() to use the same dual-path resolution pattern as _default_config_file_path():

airflow/task-sdk/src/airflow/sdk/configuration.py

Lines 36 to 58 in 8a94a43

	def _default_config_file_path(file_name: str) -> str:
	"""Get path to airflow core config.yml file."""
	# TODO: Task SDK will have its own config.yml
	# Temporary: SDK uses Core's config files during development
	# Option 1: For installed packages
	config_path = pathlib.Path(__file__).parent.parent / "config_templates" / file_name
	if config_path.exists():
	return str(config_path)
	# Option 2: Monorepo structure
	config_path = (
	pathlib.Path(__file__).parent.parent.parent.parent.parent
	/ "airflow-core"
	/ "src"
	/ "airflow"
	/ "config_templates"
	/ file_name
	)
	if config_path.exists():
	return str(config_path)
	raise FileNotFoundError(f"Could not find '{file_name}' in config_templates. ")