Hi Junio,
On Wed, 24 Aug 2016, Junio C Hamano wrote:
> Junio C Hamano <gits...@pobox.com> writes:
>
> > Mentioned elsewhere, but I think the above should be
> >
> > if (!path)
> > path = obj_context.path;
> >
> > if (obj_context.mode == S_IFINVALID)
> > obj_context.mode = 0100644;
> >
> > IOW, even when there is an explicit path supplied, we should fall
> > back to assumed "regular blob" mode, so that
> >
> > git cat-file --filters --path=README $(git rev-parse :README)
> >
> > would work as expected.
>
> Actually, I am reading the conditional the other way, but the
> conclusion "defaulting from unknown mode to regular blob is
> necessary whether the user gave us a path or not" is the same.
>
> The current code may fail if --path is not available and 40-hex that
> does not give us any context of look up is given because it won't be
> able to decide how to filter, so using "else if" would not have
> practical difference there, but conceptually it still is wrong.
Let's translate the logic
if (!path)
path = obj_context.path;
else if (obj_context.mode == S_IFINVALID)
obj_context.mode = 0100644;
into plain English.
Basically, we have two cases:
1) the user provided us with a --path option, in which case we only
override the mode if get_sha1_with_context() could not determine the
mode.
2) the user did *not* provide us with a --path, in which case we keep the
mode exactly as determined by get_sha1_with_context().
Now, the change you propose would change 2) such that we would *still*
override an undecided mode with 100644, even if the user did not bother to
specify a --path option.
It is true that it is currently impossible to infer a path from a blob ID
without being able to infer also a mode. So the question is whether it
makes sense to allow cat-file to proceed on the assumption that it is a
regular file if it does not know?
I would say: no, it does not make sense.
However, I do not want to hold this patch series up just by being
stubborn.
Will change it,
Dscho
