add tests for paths

tests/test_paths.py

@@ -0,0 +1,39 @@
+#   Copyright 2025 The PyMC Labs Developers
+#
+#   Licensed under the Apache License, Version 2.0 (the "License");
+#   you may not use this file except in compliance with the License.
+#   You may obtain a copy of the License at
+#
+#       http://www.apache.org/licenses/LICENSE-2.0
+#
+#   Unless required by applicable law or agreed to in writing, software
+#   distributed under the License is distributed on an "AS IS" BASIS,
+#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+#   See the License for the specific language governing permissions and
+#   limitations under the License.
+from pathlib import Path
+
+from pyprojroot import here
+
+from pymc_marketing import paths
+
+
+def test_root_path() -> None:
+    """Test that root path is correctly set using pyprojroot."""
+    expected_root = here()
+    assert paths.root == expected_root
+    assert paths.root.exists()
+
+
+def test_data_dir() -> None:
+    """Test that data directory path is correctly defined."""
+    expected_data_dir = here() / "data"
+    assert paths.data_dir == expected_data_dir
+    # Note: We don't assert exists() here as the data dir might not exist in CI
+    assert isinstance(paths.data_dir, Path)
+
+
+def test_paths_are_absolute() -> None:
+    """Test that all defined paths are absolute."""
+    assert paths.root.is_absolute()
+    assert paths.data_dir.is_absolute()