Update ALIGNN testing (stfc#282)

* Reduce downloads of ALIGNN

* Add pytest skip if BadZipFile

tests/test_mlip_calculators.py

@@ -1,6 +1,7 @@
 """Test configuration of MLIP calculators."""
 
 from pathlib import Path
+from zipfile import BadZipFile
 
 from chgnet.model.model import CHGNet
 from matgl import load_model
@@ -119,12 +120,15 @@ def test_invalid_device(arch):
 )
 def test_extra_mlips(arch, device, kwargs):
     """Test extra MLIPs (alignn) can be configured."""
-    calculator = choose_calculator(
-        arch=arch,
-        device=device,
-        **kwargs,
-    )
-    assert calculator.parameters["version"] is not None
+    try:
+        calculator = choose_calculator(
+            arch=arch,
+            device=device,
+            **kwargs,
+        )
+        assert calculator.parameters["version"] is not None
+    except BadZipFile:
+        pytest.skip()
 
 
 @pytest.mark.extra_mlips

tests/test_single_point.py

@@ -14,6 +14,7 @@
 
 MACE_PATH = MODEL_PATH / "mace_mp_small.model"
 SEVENNET_PATH = MODEL_PATH / "sevennet_0.pth"
+ALIGNN_PATH = MODEL_PATH / "v5.27.2024"
 
 test_data = [
     (DATA_PATH / "benzene.xyz", -76.0605725422795, "energy", "energy", {}, None),
@@ -270,7 +271,12 @@ def test_mlips(arch, device, expected_energy):
 
 
 test_extra_mlips_data = [
-    ("alignn", "cpu", -11.148092269897461, {}),
+    (
+        "alignn",
+        "cpu",
+        -11.148092269897461,
+        {"model_path": ALIGNN_PATH / "best_model.pt"},
+    ),
     ("sevennet", "cpu", -27.061979293823242, {"model_path": SEVENNET_PATH}),
     ("sevennet", "cpu", -27.061979293823242, {}),
     ("sevennet", "cpu", -27.061979293823242, {"model_path": "SevenNet-0_11July2024"}),