Re: [PATCH] tests: test applying criss-cross rename patch

[Alex Riesen <raa.lkml@gmail.com>]

2009/4/21 Junio C Hamano <gitster@pobox.com>:
> Alex Riesen <raa.lkml@gmail.com> writes:
>
>> 2009/4/11 Michał Kiedrowicz <michal.kiedrowicz@gmail.com>:
>>> +test_expect_success 'criss-cross rename' '
>>> +       mv file1 tmp &&
>>> +       mv file2 file1 &&
>>> +       mv tmp file2
>>> +'
>>> +
>>> +test_expect_success 'diff -M -B' '
>>> +       git diff -M -B > diff &&
>>> +       git reset --hard
>>> +
>>> +'
>>
>> This cannot work on systems where ctime is not trusted:
>> git diff will produce no data, as there are no changes in
>> metadata (the files are of the same size). Either make
>> the file sizes different or add a "touch file1 file2".
>
> You seem to be saying that we still have a racy-git bug somewhere.  Is
> your statement from an actual experience or a speculation?

The test reproducibly fails for me.

> If the former we have a bug to kill, not a workaround to avoid the
> issue in this test.

Maybe. As I see it, there is just not _enough_ metadata in this
particular case to notice the change without doing complete
content comparison: the size is the same, mtime is the same,
dev/ino aren't available, and ctime is marked untrusted and thus
is not used. What's left to notice the change?