Add test for parsing directory

test/unit/pybind/test_parser.py

@@ -0,0 +1,12 @@
+import nmodl
+from pathlib import Path
+import pytest
+
+
+def test_parse_directory():
+    """
+    Make sure we raise an error when parsing a directory instead of a file
+    """
+
+    with pytest.raises(RuntimeError):
+        nmodl.NmodlDriver().parse_file(str(Path(__file__).parent))