Simplify the 'pytest' setup

- Don't explicitly state 'scope="function"'.
- Use 'tmp_path_factory' instead of doing it manually.
- Set up 'conftest.py' for importing fixtures automatically.

beets/test/fixtures.py

@@ -27,15 +27,15 @@
 
 
 @pytest.fixture(scope="session")
-def resource_dir() -> Path:
+def resource_dir(pytestconfig: pytest.Config) -> Path:
     """
     A fixture returning the resource directory for tests.
     """
 
-    return Path(__file__).parents[2] / "test" / "rsrc"
+    return pytestconfig.rootpath / "test" / "rsrc"
 
 
-@pytest.fixture(scope="function")
+@pytest.fixture
 def config(
     tmp_path: Path,
     monkeypatch: pytest.MonkeyPatch,
@@ -67,9 +67,9 @@ def config(
     beets.config._materialized = False
 
 
-@pytest.fixture(scope="function")
+@pytest.fixture
 def library(
-    tmp_path: Path,
+    tmp_path_factory: pytest.TempPathFactory,
     config: Configuration,
     monkeypatch: pytest.MonkeyPatch,
 ) -> Iterator[Library]:
@@ -78,8 +78,7 @@ def library(
     """
 
     # Beets needs a location to store library contents.
-    lib_dir = tmp_path / "lib_dir"
-    lib_dir.mkdir(exist_ok=False)
+    lib_dir = tmp_path_factory.mktemp("lib_dir")
     monkeypatch.setenv("BEETSDIR", str(lib_dir))
 
     # Create the Beets library object.

test/conftest.py

@@ -0,0 +1,20 @@
+# This file is part of beets.
+# Copyright 2024, Arav K.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+
+"""
+Automatic configuration for `pytest`.
+"""
+
+# Pull in Beets' test fixtures.
+pytest_plugins = "beets.test.fixtures"

test/plugins/test_fish.py

@@ -24,11 +24,8 @@
 from beets.library import Library
 from beetsplug.fish import FishPlugin
 
-# Tell 'pytest' to pull in Beets' test fixtures.
-pytest_plugins = "beets.test.fixtures"
 
-
-@pytest.fixture(scope="function")
+@pytest.fixture
 def fish_plugin() -> FishPlugin:
     """
     A fixture returning an instance of the `fish` plugin.