Subject: Re: What's cooking in git.git (Jan 2018, #04; Wed, 31)

From: Ævar Arnfjörð Bjarmason <[email-masked]>
Date: Fri, 02 Feb 2018 20:29:32 +0100

On Fri, Feb 02 2018, Junio C. Hamano jotted:

> Ævar Arnfjörð Bjarmason <[email-masked]> writes:
>
>> On Thu, Feb 01 2018, Junio C. Hamano jotted:
>>
>>> * nd/fix-untracked-cache-invalidation (2018-01-24) 5 commits
>>>  - dir.c: stop ignoring opendir() error in open_cached_dir()
>>>  - update-index doc: note a fixed bug in the untracked cache
>>>  - dir.c: fix missing dir invalidation in untracked code
>>>  - dir.c: avoid stat() in valid_cached_dir()
>>>  - status: add a failing test showing a core.untrackedCache bug
>>>
>>>  Some bugs around "untracked cache" feature have been fixed.
>>>
>>>  Will merge to 'next'.
>>
>> The "update-index doc: note a fixed bug in the untracked cache" needs to
>> be amended so it doesn't say "Before 2.16, ":
>
> True; we could just say "earlier", but I am inclined to suggest that
> we get drop it altogether.  Description of historical bugs is of no
> interest with the version that already fixes them, so the _only_
> value the doc update adds is to tell readers that the untracked
> cache feature is still not well proven, and core.untrackedCache may
> serve as an escape hatch from its bugs by disabling the mechanism
> added for the feature.  I am *not* opposed to a replacement of the
> patch that just says something like "This feature has been cause of
> bugs even in recent versions of Git, and you may want to disable it
> as a workaround when you are hit by an otherwise undiscovered bug in
> this area", though.

 - It's my experience that most users today who aren't *nix graybeards
   don't use the documentation shipped on their system as their primary
   source for docs.

   They go to Google and might find the manpage there. Thus this
   documentation will be read by users on pre-2.17 (or whenever this bug
   fix gets included).

 - This is very useful information if you're deploying
   core.untrackedCache across a site with differing git versions. Just
   because you have 2.17 doesn't mean everywhere you're about to deploy
   core.untrackedCache does.

 - In general I agree that we shouldn't be documenting old bugs, but I
   think in this case it makes sense since the bug's really bad. Without
   thinking to disable core.untrackedCache there's seemingly no way to
   fix it without wiping away the index, which might lose you work.