Hi,
On 2020-09-23 16:44, Johannes Schindelin wrote:
> Hi Junio,
>
> On Wed, 23 Sep 2020, Junio C Hamano wrote:
>
>> Johannes Schindelin <Johannes.Schindelin@xxxxxx> writes:
>>
>>> I believe that that is exactly the reason why we want this:
>>>
>>> - same_contents = oideq(&one->oid, &two->oid);
>>> + same_contents = one->oid_valid && two->oid_valid ?
>>> oideq(&one->oid, &two->oid) : !strcmp(one->data, two->data);
>>
>> Not quite. The other side should either be
>>
>> one->size == two->size && !memcmp(...)
Thanks for all the feedback, that was enlightening. Although I have been
silent the past few days I watched this thread with interest.
So as Junio pointed out this is merely an optimization - the range-diff
test that I corrected also showed two 0-line diffs and I realized
there's a block further down that should explicitly removes them, under
else if (!same_contents) {
We can even remove same_contents entirely and everything work just fine
after adjusting the range-diff test - the logic is correct and
underlying functions already DTRT.
My next patch simplifies the test down to:
same_contents = one->oid_valid && two->oid_valid &&
oideq(&one->oid, &two->oid);
My understanding is that oid_valid will never be true for a modified
(even mode change) or out of tree file so it's a valid assumption.
I'll also rename that variable to "same_oid" - the current name is
misleading both ways (true doesn't means there will be diffs, false
doesn't mean contents differs).
Regards,
Thomas
