Re: [PATCH v3 2/9] cache-tree: simplify verify_cache() prototype

[Derrick Stolee <stolee@gmail.com>]

On 1/23/2021 4:10 PM, Junio C Hamano wrote:
> Elijah Newren <newren@gmail.com> writes:
> 
>>> -       for (i = 0; i < entries - 1; i++) {
>>> +       for (i = 0; i + 1 < istate->cache_nr; i++) {
>>>                 /* path/file always comes after path because of the way
>>>                  * the cache is sorted.  Also path can appear only once,
>>>                  * which means conflicting one would immediately follow.
>>>                  */
>>> -               const struct cache_entry *this_ce = cache[i];
>>> -               const struct cache_entry *next_ce = cache[i + 1];
>>> +               const struct cache_entry *this_ce = istate->cache[i];
>>> +               const struct cache_entry *next_ce = istate->cache[i + 1];
>>
>> Makes sense.  Thanks for explaining the i + 1 < istate->cache_nr bit
>> in the commit message; made it easier to read through quickly.  I'm
>> curious if it deserves a comment in the code too, since it does feel
>> slightly unusual.
> 
> I think this is entirely my fault.
> 
> It probably reads more natural to start from 1 and interate through
> to the end of the array, comparing the current one with the previous
> entry, i.e.
> 
> 	for (i = 1; i < istate->cache_nr; i++) {
>         	prev = cache[i - 1];
> 		this = cache[i];
>                 compare(prev, this);

This would be another natural way to make the loop extremely clear.

It's a bigger diff, changing the names of 'this' and 'next', but
perhaps worthwhile.

Thanks,
-Stolee