make pybtex optional

Author: DanielYang59

pyproject.toml

@@ -62,7 +62,6 @@ dependencies = [
     "palettable>=3.3.3",
     "pandas>=2",
     "plotly>=4.5.0,<6.0.0",
-    "pybtex>=0.24.0",
     "requests>=2.32",
     "ruamel.yaml>=0.17.0",
     # scipy<1.14.1 is incompatible with NumPy 2.0 on Windows
@@ -110,6 +109,7 @@ optional = [
     "matplotlib>=3.8",
     "openbabel-wheel>=3.1.1.20",
     "phonopy>=2.33.3",
+    "pybtex>=0.24.0",  # TODO: don't work on MacOS Python 3.13
     "seekpath>=2.0.1",
 ]
 # moyopy[interface] includes ase

src/pymatgen/io/cif.py

@@ -1357,8 +1357,8 @@ def get_bibtex_string(self) -> str:
         """
         try:
             from pybtex.database import BibliographyData, Entry
-        except ImportError:
-            raise RuntimeError("Bibliographic data extraction requires pybtex.")
+        except ImportError as exc:
+            raise RuntimeError("Bibliographic data extraction requires pybtex.") from exc
 
         bibtex_keys: dict[str, tuple[str, ...]] = {
             "author": ("_publ_author_name", "_citation_author_name"),

src/pymatgen/util/provenance.py

@@ -9,17 +9,10 @@
 from io import StringIO
 from typing import TYPE_CHECKING, NamedTuple
 
-from monty.dev import requires
 from monty.json import MontyDecoder, MontyEncoder
 
 from pymatgen.core.structure import Molecule, Structure
 
-try:
-    from pybtex import errors
-    from pybtex.database.input import bibtex
-except ImportError:
-    pybtex = bibtex = errors = None
-
 if TYPE_CHECKING:
     from collections.abc import Sequence
     from typing import Any
@@ -37,7 +30,6 @@
 MAX_BIBTEX_CHARS: int = 20_000  # maximum number of characters for BibTeX reference
 
 
-@requires(bibtex is not None, "pybtex is not available")
 def is_valid_bibtex(reference: str) -> bool:
     """Use pybtex to validate that a reference is in proper BibTeX format.
 
@@ -47,6 +39,12 @@ def is_valid_bibtex(reference: str) -> bool:
     Returns:
         bool: True if reference is valid BibTeX.
     """
+    try:
+        from pybtex import errors
+        from pybtex.database.input import bibtex
+    except ImportError as exc:
+        raise ImportError("pybtex is not available") from exc
+
     # str is necessary since pybtex seems to have an issue with unicode.
     # The filter expression removes all non-ASCII characters.
     str_io = StringIO(reference.encode("ascii", "ignore").decode("ascii"))

tests/analysis/test_cost.py

@@ -2,11 +2,19 @@
 
 from unittest import TestCase
 
+import pytest
 from pytest import approx
 
 from pymatgen.analysis.cost import CostAnalyzer, CostDBCSV, CostDBElements
 from pymatgen.util.testing import TEST_FILES_DIR
 
+try:
+    # Not using find_spec because it would error out during import
+    import pybtex.database  # noqa: F401
+
+except ImportError:
+    pytest.skip("pybtex is not available", allow_module_level=True)
+
 TEST_DIR = f"{TEST_FILES_DIR}/analysis/cost"
 
 

tests/io/test_cif.py

@@ -13,6 +13,7 @@
 
 try:
     import pybtex
+    import pybtex.database
 except ImportError:
     pybtex = None
 
@@ -165,6 +166,7 @@ def test_long_loop(self):
 
 
 class TestCifIO(PymatgenTest):
+    @pytest.mark.skipif(pybtex is None, reason="pybtex not present")
     def test_cif_parser(self):
         parser = CifParser(f"{TEST_FILES_DIR}/cif/LiFePO4.cif")
         for struct in parser.parse_structures():

tests/util/test_provenance.py

@@ -11,6 +11,13 @@
 from pymatgen.core.structure import Molecule, Structure
 from pymatgen.util.provenance import Author, HistoryNode, StructureNL
 
+try:
+    # Not using find_spec because it would error out during import
+    import pybtex.database  # noqa: F401
+
+except ImportError:
+    pytest.skip("pybtex is not available", allow_module_level=True)
+
 __author__ = "Anubhav Jain"
 __credits__ = "Shyue Ping Ong"
 __copyright__ = "Copyright 2012, The Materials Project"