Testing: Refactor config fixtures so that a temp file is generated an…

…d set as Rucio config when no file is found

With this refactor, devs should be able to use pytest throughout Rucio without needing to set up a full Rucio environment

tests/conftest.py

@@ -577,8 +577,43 @@ def core_config_mock(request: pytest.FixtureRequest) -> "Iterator[None]":
         yield
 
 
+@pytest.fixture(scope="session")
+def config_parser_from_temp_file() -> "Iterator[ConfigParser]":
+    """
+    Session-scoped fixture that generates a temporary file, sets it as the Rucio config file,
+    and provides a ConfigParser based on this file.
+    Used to test when no Rucio config file is already present.
+    """
+    import tempfile
+
+    from rucio.common.config import Config
+
+    # Create a temporary file
+    with tempfile.NamedTemporaryFile(delete=True) as temp:
+        # Set the environment variable to the name of the temporary file
+        with pytest.MonkeyPatch.context() as mp:
+            mp.setenv("RUCIO_CONFIG", temp.name)
+            yield Config().parser
+
+
+@pytest.fixture()
+def config_parser(config_parser_mock_from_temp_file) -> "Iterator[ConfigParser]":
+    """
+    Fixture that provides a ConfigParser based on the available Rucio config.
+    """
+    from rucio.common.config import Config
+    from rucio.common.exception import ConfigNotFound
+
+    try:
+        parser = Config().parser
+    except ConfigNotFound:
+        parser = config_parser_mock_from_temp_file
+
+    yield parser
+
+
 @pytest.fixture
-def file_config_mock(request: pytest.FixtureRequest) -> "Iterator[ConfigParser]":
+def file_config_mock(request: pytest.FixtureRequest, config_parser) -> "Iterator[ConfigParser]":
     """
     Fixture which allows to have an isolated in-memory configuration file instance which
     is not persisted after exiting the fixture.
@@ -588,21 +623,20 @@ def file_config_mock(request: pytest.FixtureRequest) -> "Iterator[ConfigParser]"
     """
     from unittest import mock
 
-    from rucio.common.config import Config, config_add_section, config_has_section, config_set
+    from rucio.common.config import config_add_section, config_has_section, config_set
 
     # Get the fixture parameters
     overrides = []
     params = __get_fixture_param(request)
     if params:
         overrides = params.get("overrides", overrides)
 
-    parser = Config().parser
-    with mock.patch('rucio.common.config.get_config', side_effect=lambda: parser):
+    with mock.patch('rucio.common.config.get_config', side_effect=lambda: config_parser):
         for section, option, value in (overrides or []):
             if not config_has_section(section):
                 config_add_section(section)
             config_set(section, option, value)
-        yield parser
+        yield config_parser
 
 
 @pytest.fixture