Git.version_info type annotation is overly specific in length · Issue #1830 · gitpython-developers/GitPython (original) (raw)

The version_info property is declared to be a length-4 tuple:

@property
def version_info(self) -> Tuple[int, int, int, int]:
"""
:return: tuple(int, int, int, int) tuple with integers representing the major, minor
and additional version numbers as parsed from git version.
This value is generated on demand and is cached.
"""
return self._version_info

But it often has fewer values, which is intentional:

def _set_cache_(self, attr: str) -> None:
if attr == "_version_info":
# We only use the first 4 numbers, as everything else could be strings in fact (on Windows).
process_version = self._call_process("version") # Should be as default *args and **kwargs used.
version_numbers = process_version.split(" ")[2]
self._version_info = cast(
Tuple[int, int, int, int],
tuple(int(n) for n in version_numbers.split(".")[:4] if n.isdigit()),
)
else:
super()._set_cache_(attr)
# END handle version info

So the type annotation should be changed, but I am unsure what it should be changed to, whether any additional documentation should be added, and whether having fewer than some number of numeric fields should be treated as an error and cause an exception to be raised.

If the type annotation should reflect that only a few specific lengths are reasonable, then it could be expressed as a Union of specific-length Tuple types. Otherwise it could be expressed as a variable-length tuple by writing the type as Tuple[int, ...].

I recommend this be solved in such a way that the cast can be removed. Currently, the cast is working around ambiguity in how the return type is intended to be understood.

This is separate from #1829, though I noticed it while looking into that and they could possibly be fixed (or improved or otherwise closed) together.