Bug in DictSet.kpoints due to operator precedence

[janosh]

@shyuep I think there's a subtle operator precedence bug here:

pymatgen/pymatgen/io/vasp/sets.py

Lines 633 to 638 in ed66c97

	if (
	self.user_incar_settings.get("KSPACING")
	or self._config_dict["INCAR"].get("KSPACING")
	and self.user_kpoints_settings == {}
	):
	return None

and has higher precedence than or but unless I'm mistaken we actually want to evaluate the or first. The thing that throws me off is why this wasn't caught before.

if (
    self.user_incar_settings.get("KSPACING") or self._config_dict["INCAR"].get("KSPACING")
) and self.user_kpoints_settings == {}:

[shyuep]

I agree. I did not write this though. I think the switch to KSPACING is relatively recent.