Subject: Re: [PATCH v2 1/2] t1092: add tests for `git diff-files`

From: Junio C Hamano <[email-masked]>
Date: Wed, 08 Mar 2023 14:40:07 -0800

Shuqi Liang <[email-masked]> writes:

>> We create a new directory that is outside the cone, with or without
>> using the sparse-index feature.  We know we are violating the cone,
>> and have to override the safety with the "--sparse" option.  OK.
>>
>> What output do we expect out of "git add" to match in the two cases?
>>
>> > +     #file present on-disk without modifications
>> > +     test_sparse_match git diff-files &&
>> > +     test_sparse_match git diff-files newdirectory/testfile &&
>>
>> As "diff-files" is about comparing between the index and the working
>> tree, the new path should not appear in the output when the sparse
>> checkout feature with or without the sparse-index feature is NOT in
>> use.  Does the picture get different when we are sparse?  IOW, would
>> we notice that we now have newdirectory/testfile that is supposed to
>> be missing in the index and show that in the output?
>
> I'm a bit caught up here.
> Do you mean I need to add a test for "git add" also?

Not really.  The above two tests are happy with _any_ output coming
out of "git diff-files" (and "git diff-files nd/tf") as long as they
match between sparse checkouts, one of which uses and the other does
not use the sparse index feature.  I was wondering if we want to be
a bit stricter than that.  Thinks like "not only the two output must
match, they both must be empty".