add test for M3GNetSite and M3GNetStructrue describers

tests/describers/test_m3gnet.py

@@ -0,0 +1,36 @@
+from __future__ import annotations
+
+import numpy as np
+import unittest
+
+from pymatgen.core import Lattice, Structure
+
+try:
+    from m3gnet.models import M3GNet
+except ImportError:
+    M3GNet = None
+
+from maml.describers import M3GNetStructure, M3GNetSite
+
+
+@unittest.skipIf(M3GNet is None, "M3GNet package is required")
+class M3GNetTest(unittest.TestCase):
+    @classmethod
+    def setUpClass(cls):
+        cls.s = Structure.from_spacegroup(
+            "Fm-3m", Lattice.cubic(5.69169), ["Na", "Cl"], [[0, 0, 0], [0, 0, 0.5]]
+        )
+        cls.m3gnet_struct = M3GNetStructure()
+        cls.m3gnet_site = M3GNetSite(feature_batch="pandas_concat")
+
+    def test_m3gnet_site_transform(self):
+        atom_features2 = self.m3gnet_site.transform([self.s] * 2)
+        self.assertListEqual(list(np.array(atom_features2).shape), [16, 64])
+
+    def test_m3gnet_structure_transform(self):
+        struct_feature2 = self.m3gnet_struct.transform([self.s] * 2)
+        self.assertListEqual(list(np.array(struct_feature2).shape), [2, 128])
+
+
+if __name__ == "__main__":
+    unittest.main()