fix: parse Gromacs frames for bad-box checks

Fixes #1905

Coding-Agent: Codex

Codex-Version: codex-cli 0.149.0

Model: gpt-5.6-sol

Reasoning-Effort: xhigh

Author: njzjz-bot

dpgen/generator/run.py

@@ -2973,7 +2973,7 @@ def _trust_limitation_check(sys_idx, lim):
                 ffmt = "lammps/dump"
             elif model_devi_engine == "gromacs":
                 conf_name = os.path.join(conf_name, str(ii) + ".gromacstrj")
-                ffmt = "lammps/dump"
+                ffmt = "gromacs/gro"
             elif model_devi_engine == "amber":
                 conf_name = os.path.join(tt, "rc.nc")
                 rst_name = os.path.abspath(os.path.join(tt, "init.rst7"))

tests/generator/test_check_bad_box.py

@@ -23,3 +23,8 @@ def test_height_ratio(self):
         conf_bad = os.path.join(dirname, "check_bad_box", "bad.height.POSCAR")
         self.assertTrue(check_bad_box(conf_bad, "height_ratio:5", fmt="vasp/POSCAR"))
         self.assertFalse(check_bad_box(conf_bad, "length_ratio:5", fmt="vasp/POSCAR"))
+
+    def test_gromacs_frame_format(self):
+        dirname = os.path.dirname(__file__)
+        conf = os.path.join(dirname, "gromacs", "outputs", "traj", "0.gromacstrj")
+        self.assertFalse(check_bad_box(conf, "length_ratio:5", fmt="gromacs/gro"))