Invalid map format handling

tests/test_invalid_format.py

@@ -0,0 +1,13 @@
+import os
+from pathlib import Path
+
+import pytest
+
+from pytiled_parser import UnknownFormat, parse_map
+
+TESTS_DIR = Path(os.path.dirname(os.path.abspath(__file__)))
+MAP_FILE = TESTS_DIR / "test_data/invalid_format.garbage"
+
+def test_map_invalid_format():
+    with pytest.raises(UnknownFormat) as e:
+        parse_map(MAP_FILE)