Hacks for Pint compatibility

Author: mattwthompson

openff/toolkit/topology/molecule.py

@@ -268,7 +268,7 @@ def __init__(
 
         # Use the setter here, since it will handle either ints or Quantities
         # and it is designed to quickly process ints
-        self.formal_charge = formal_charge
+        self.formal_charge = formal_charge  # type: ignore[assignment]
         self._is_aromatic = is_aromatic
         self._stereochemistry = stereochemistry
         if name is None:
@@ -308,9 +308,13 @@ def to_dict(self) -> dict[str, Union[None, str, int, bool, dict[Any, Any]]]:
         """
         # TODO: Should this be implicit in the atom ordering when saved?
         # atom_dict['molecule_atom_index'] = self._molecule_atom_index
+
+        # trust that the unit is e
+        formal_charge: int = self._formal_charge.m  # type: ignore
+
         return {
             "atomic_number": self._atomic_number,
-            "formal_charge": self._formal_charge.m,  # Trust that the unit is e
+            "formal_charge": formal_charge,
             "is_aromatic": self._is_aromatic,
             "stereochemistry": self._stereochemistry,
             "name": self._name,

openff/toolkit/utils/builtin_wrapper.py

@@ -131,7 +131,7 @@ def assign_partial_charges(
             partial_charges = [0.0] * molecule.n_atoms
 
         elif partial_charge_method == "formal_charge":
-            partial_charges = [float(atom.formal_charge.m) for atom in molecule.atoms]
+            partial_charges = [float(atom.formal_charge.m) for atom in molecule.atoms]  # type: ignore
 
         molecule.partial_charges = Quantity(partial_charges, unit.elementary_charge)