add temporary directory fixture for pytest

tests/conftest.py

@@ -0,0 +1,23 @@
+from pathlib import Path
+
+import pytest
+
+
+def pytest_addoption(parser):
+    """Sets up optional argument to keep temporary testing directory."""
+    parser.addoption(
+        "--keep-tmp",
+        action="store_true",
+        help="Keep temporary directory after testing. Useful for debugging.",
+    )
+
+
+@pytest.fixture(scope="class")
+def pass_options(request):
+    """Adds optional argument to a test class."""
+    request.cls.KEEP_TMP = request.config.getoption("--keep-tmp")
+
+
+@pytest.fixture(scope="function", autouse=True)
+def temp_output_dir(tmpdir_factory) -> Path:
+    return Path(tmpdir_factory.mktemp("tmp-"))