instead of failing, files woith no parser are now returned as strings in

VaspDir.

Author: shyuep

src/pymatgen/io/vasp/outputs.py

@@ -5672,15 +5672,20 @@ def __iter__(self):
     def __getitem__(self, item):
         if item in self._parsed_files:
             return self._parsed_files[item]
+        fpath = self.path / item
+
+        if not (self.path / item).exists():
+            raise ValueError(f"{item} not found in {self.path}. List of files are {self.files}.")
+
         for k, cls_ in VaspDir.FILE_MAPPINGS.items():
             if k in item:
                 try:
-                    self._parsed_files[item] = cls_.from_file(self.path / item)
+                    self._parsed_files[item] = cls_.from_file(fpath)
                 except AttributeError:
-                    self._parsed_files[item] = cls_(self.path / item)
+                    self._parsed_files[item] = cls_(fpath)
 
                 return self._parsed_files[item]
-        if (self.path / item).exists():
-            raise RuntimeError(f"Unable to parse {item}. Supported files are {list(VaspDir.FILE_MAPPINGS.keys())}.")
 
-        raise ValueError(f"{item} not found in {self.path}. List of files are {self.files}.")
+        warnings.warn(f"No parser defined for {item}. Full text of file is returned as a string.", UserWarning)
+        with zopen(fpath, "rt") as f:
+            return f.read()

tests/io/vasp/test_outputs.py

@@ -2110,12 +2110,14 @@ def test_getitem(self):
         d = VaspDir(f"{TEST_FILES_DIR}/io/vasp/fixtures/relaxation")
         assert len(d) == 5
         assert d["OUTCAR"].run_stats["cores"] == 8
-        d = VaspDir(f"{TEST_FILES_DIR}/io/vasp/outputs")
-        with pytest.raises(RuntimeError, match=r"Unable to parse IBZKPT.*"):
-            d["IBZKPT.lobster"]
+
         d = VaspDir(f"{TEST_FILES_DIR}/io/vasp/fixtures/scan_relaxation")
         assert len(d) == 2
         assert d["vasprun.xml.gz"].incar["METAGGA"] == "R2scan"
 
         with pytest.raises(ValueError, match="hello not found"):
             d["hello"]
+
+        d = VaspDir(f"{TEST_FILES_DIR}/io/vasp/outputs")
+        with pytest.warns(UserWarning, match=r"No parser defined for IBZKPT.*"):
+            assert isinstance(d["IBZKPT.lobster"], str)