Re: [PATCH v13 2/9] refs: standardize output of refs_read_symbolic_ref

> On Tue, Nov 19, 2024 at 03:54:05PM +0900, Junio C Hamano wrote:
>> Patrick Steinhardt <ps@pks.im> writes:
>> > The reason why I've been proposing to return negative is because we have
>> > the idiom of checking `err < 0` in many places, so a function that
>> > returns a positive value in the case where it didn't return the expected
>> > result can easily lead to bugs.
>> 
>> I agree with the general reasoning.  I am saying this may or may not
>> be an error, and if it turns out that it is not an error but is just
>> one of the generally expected outcome, treating it as an error and
>> having "if (status < 0)" to lump the case together with other error
>> cases may not be nice to the callers.
>
> The question to me is whether the function returns something sensible in
> all non-error cases that a caller can use properly without having to
> explicitly check for the value. And I'd say that this is not the case
> with `refs_read_symbolic_ref()`, which wouldn't end up setting the value
> of `referent`.
>
> So regardless of whether we define this as error or non-error, the
> caller would have to exlicitly handle the case where it's not a symref
> in order to make sense of it because the result is not well-defined.