fix: generate MEAM and EAM-alloy commands

Fixes #1896

Coding-Agent: Codex

Codex-Version: codex-cli 0.149.0

Model: gpt-5.6-sol

Reasoning-Effort: xhigh

Author: njzjz-bot

dpgen/auto_test/Lammps.py

@@ -54,7 +54,7 @@ def set_model_param(self):
             }
         elif self.inter_type == "meam":
             model_name = list(map(os.path.basename, self.model))
-            self.model_param = {"model_name": [model_name], "param_type": self.type_map}
+            self.model_param = {"model_name": model_name, "param_type": self.type_map}
         else:
             model_name = os.path.basename(self.model)
             self.model_param = {"model_name": [model_name], "param_type": self.type_map}

dpgen/auto_test/lib/lammps.py

@@ -148,7 +148,7 @@ def inter_eam_fs(param):  # 06/08 eam.fs interaction
 def inter_eam_alloy(param):  # 06/08 eam.alloy interaction
     ret = ""
     line = "pair_style      eam/alloy \n"
-    line += "pair_coeff      * * {} ".format(param["model_name"])
+    line += "pair_coeff      * * {} ".format(param["model_name"][0])
     for ii in param["param_type"]:
         line += ii + " "
     line += "\n"

tests/auto_test/test_lammps.py

@@ -11,7 +11,7 @@
 
 from dpgen.auto_test.common_equi import make_equi, run_equi
 from dpgen.auto_test.Lammps import Lammps
-from dpgen.auto_test.lib.lammps import inter_deepmd
+from dpgen.auto_test.lib.lammps import inter_deepmd, inter_eam_alloy, inter_meam
 
 from .context import setUpModule  # noqa: F401
 
@@ -72,6 +72,32 @@ def test_set_model_param(self):
         }
         self.assertEqual(model_param, self.Lammps.model_param)
 
+    def test_meam_model_parameters_generate_two_file_command(self):
+        interaction = {
+            "type": "meam",
+            "model": ["lammps_input/meam.lib", "lammps_input/Al.meam"],
+            "type_map": {"Al": 0},
+        }
+        calculator = Lammps(interaction, self.source_path + "/Al-fcc.vasp")
+        calculator.set_model_param()
+
+        self.assertEqual(calculator.model_param["model_name"], ["meam.lib", "Al.meam"])
+        command = inter_meam(calculator.model_param)
+        self.assertIn("pair_coeff      * * meam.lib Al Al.meam Al", command)
+
+    def test_eam_alloy_command_uses_plain_filename(self):
+        interaction = {
+            "type": "eam_alloy",
+            "model": "lammps_input/Al.eam.alloy",
+            "type_map": {"Al": 0},
+        }
+        calculator = Lammps(interaction, self.source_path + "/Al-fcc.vasp")
+        calculator.set_model_param()
+
+        command = inter_eam_alloy(calculator.model_param)
+        self.assertIn("pair_coeff      * * Al.eam.alloy Al", command)
+        self.assertNotIn("['Al.eam.alloy']", command)
+
     def test_make_potential_files(self):
         cwd = os.getcwd()
         abs_equi_path = os.path.abspath(self.equi_path)