Add unittests for assets and downloader functionality (#2095)

* Apply suggestions from code review
* Use BASE_VIDEO_URL constant in test instead of hard-coded URL (#2097)
* Replace hard-coded URL with BASE_VIDEO_URL constant in test
* Fix non-deterministic test_invalid_asset by patching Path.exists (#2096)
* Fix test_invalid_asset to be deterministic by patching Path.exists

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Borda <6035284+Borda@users.noreply.github.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <198982749+Copilot@users.noreply.github.com>

test/assets/test_downloader.py

@@ -0,0 +1,141 @@
+from unittest.mock import MagicMock, mock_open, patch
+
+import pytest
+
+from supervision.assets.downloader import download_assets, is_md5_hash_matching
+from supervision.assets.list import VideoAssets
+
+
+class TestMD5HashMatching:
+    def test_file_exists_matching_hash(self):
+        """Test is_md5_hash_matching when file exists and hash matches."""
+        test_content = b"test content"
+        test_hash = "9473fdd0d880a43c21b7778d34872157"  # MD5 of "test content"
+
+        with (
+            patch("builtins.open", mock_open(read_data=test_content)),
+            patch("os.path.exists", return_value=True),
+        ):
+            assert is_md5_hash_matching("dummy_file", test_hash)
+
+    def test_file_exists_not_matching_hash(self):
+        """Test is_md5_hash_matching when file exists but hash doesn't match."""
+        test_content = b"test content"
+        wrong_hash = "wrong_hash"
+
+        with (
+            patch("builtins.open", mock_open(read_data=test_content)),
+            patch("os.path.exists", return_value=True),
+        ):
+            assert not is_md5_hash_matching("dummy_file", wrong_hash)
+
+    def test_file_not_exists(self):
+        """Test is_md5_hash_matching when file doesn't exist."""
+        with patch("os.path.exists", return_value=False):
+            assert not is_md5_hash_matching("nonexistent_file", "some_hash")
+
+
+class TestDownloadAssets:
+    @patch("builtins.print")
+    @patch("supervision.assets.downloader.is_md5_hash_matching", return_value=True)
+    @patch("pathlib.Path.exists", return_value=True)
+    def test_already_exists_and_valid(self, mock_exists, mock_md5, mock_print):
+        """Test download_assets when file already exists and is valid."""
+        filename = "vehicles.mp4"
+        result = download_assets(filename)
+        assert result == filename
+        mock_print.assert_called_with(f"{filename} asset download complete. \n")
+
+    @patch("supervision.assets.downloader.download_assets", return_value="vehicles.mp4")
+    @patch("os.remove")
+    @patch("supervision.assets.downloader.is_md5_hash_matching", return_value=False)
+    @patch("pathlib.Path.exists", return_value=True)
+    def test_already_exists_but_corrupted(
+        self, mock_exists, mock_md5, mock_remove, mock_recursive
+    ):
+        """Test download_assets when file exists but is corrupted (re-downloads)."""
+        filename = "vehicles.mp4"
+        result = download_assets(filename)
+        assert result == filename
+        mock_recursive.assert_called_with(filename)
+
+    @patch("builtins.print")
+    @patch("pathlib.Path.open", new_callable=mock_open)
+    @patch("pathlib.Path.mkdir")
+    @patch("pathlib.Path.exists", return_value=False)
+    @patch("supervision.assets.downloader.copyfileobj")
+    @patch("supervision.assets.downloader.tqdm")
+    @patch("supervision.assets.downloader.get")
+    def test_download_new_file(
+        self,
+        mock_get,
+        mock_tqdm,
+        mock_copyfileobj,
+        mock_exists,
+        mock_mkdir,
+        mock_open_file,
+        mock_print,
+    ):
+        """Test download_assets downloading a new file."""
+        filename = "vehicles.mp4"
+
+        mock_response = MagicMock()
+        mock_response.headers = {"Content-Length": "100"}
+        mock_response.raw = MagicMock()
+        mock_response.raise_for_status = MagicMock()
+        mock_get.return_value = mock_response
+
+        mock_tqdm.wrapattr.return_value.__enter__ = MagicMock(
+            return_value=mock_response.raw
+        )
+        mock_tqdm.wrapattr.return_value.__exit__ = MagicMock()
+
+        result = download_assets(filename)
+        assert result == filename
+        mock_print.assert_called_with(f"Downloading {filename} assets \n")
+        mock_get.assert_called_once()
+        mock_response.raise_for_status.assert_called_once_with()
+        mock_copyfileobj.assert_called_once()
+
+    @patch("pathlib.Path.exists", return_value=False)
+    def test_invalid_asset(self, mock_exists):
+        """Test download_assets with invalid asset name."""
+        invalid_filename = "invalid.mp4"
+
+        with pytest.raises(ValueError) as exc_info:
+            download_assets(invalid_filename)
+
+        assert "Invalid asset" in str(exc_info.value)
+        assert "vehicles.mp4" in str(exc_info.value)
+
+    @patch("builtins.print")
+    @patch("pathlib.Path.open", new_callable=mock_open)
+    @patch("pathlib.Path.mkdir")
+    @patch("supervision.assets.downloader.copyfileobj")
+    @patch("supervision.assets.downloader.tqdm")
+    @patch("supervision.assets.downloader.get")
+    @patch("pathlib.Path.exists", return_value=False)
+    def test_with_enum(
+        self,
+        mock_exists,
+        mock_get,
+        mock_tqdm,
+        mock_copyfileobj,
+        mock_mkdir,
+        mock_open_file,
+        mock_print,
+    ):
+        """Test download_assets with VideoAssets enum."""
+        asset = VideoAssets.VEHICLES
+
+        mock_response = MagicMock()
+        mock_response.headers = {"Content-Length": "100"}
+        mock_response.raw = MagicMock()
+        mock_response.raise_for_status = MagicMock()
+        mock_get.return_value = mock_response
+
+        mock_tqdm.wrapattr.return_value.__enter__ = MagicMock()
+        mock_tqdm.wrapattr.return_value.__exit__ = MagicMock()
+
+        result = download_assets(asset)
+        assert result == asset.value

test/assets/test_list.py

@@ -0,0 +1,48 @@
+from supervision.assets.list import BASE_VIDEO_URL, VIDEO_ASSETS, VideoAssets
+
+
+def test_video_assets_list():
+    """Test that VideoAssets.list() returns all video filenames."""
+    expected_filenames = [
+        "vehicles.mp4",
+        "milk-bottling-plant.mp4",
+        "vehicles-2.mp4",
+        "grocery-store.mp4",
+        "subway.mp4",
+        "market-square.mp4",
+        "people-walking.mp4",
+        "beach-1.mp4",
+        "basketball-1.mp4",
+        "skiing.mp4",
+    ]
+    assert VideoAssets.list() == expected_filenames
+
+
+def test_video_assets_enum_values():
+    """Test that VideoAssets enum members have correct values."""
+    assert VideoAssets.VEHICLES.value == "vehicles.mp4"
+    assert VideoAssets.MILK_BOTTLING_PLANT.value == "milk-bottling-plant.mp4"
+    assert VideoAssets.VEHICLES_2.value == "vehicles-2.mp4"
+    assert VideoAssets.GROCERY_STORE.value == "grocery-store.mp4"
+    assert VideoAssets.SUBWAY.value == "subway.mp4"
+    assert VideoAssets.MARKET_SQUARE.value == "market-square.mp4"
+    assert VideoAssets.PEOPLE_WALKING.value == "people-walking.mp4"
+    assert VideoAssets.BEACH.value == "beach-1.mp4"
+    assert VideoAssets.BASKETBALL.value == "basketball-1.mp4"
+    assert VideoAssets.SKIING.value == "skiing.mp4"
+
+
+def test_video_assets_dict_keys():
+    """Test that VIDEO_ASSETS has all VideoAssets as keys."""
+    expected_keys = {asset.value for asset in VideoAssets}
+    assert set(VIDEO_ASSETS.keys()) == expected_keys
+
+
+def test_video_assets_dict_values():
+    """Test that VIDEO_ASSETS values are tuples of (url, md5_hash)."""
+    for filename, (url, md5_hash) in VIDEO_ASSETS.items():
+        assert isinstance(url, str)
+        assert url.startswith(BASE_VIDEO_URL)
+        assert url.endswith(filename)
+        assert isinstance(md5_hash, str)
+        assert len(md5_hash) == 32  # MD5 hash length