* Re: Find commit that referenced a blob first
2018-07-19 21:19 ` Stefan Beller
@ 2018-07-19 21:45 ` Lars Schneider
2018-07-19 21:47 ` Jeff King
2018-07-19 22:38 ` Junio C Hamano
2 siblings, 0 replies; 6+ messages in thread
From: Lars Schneider @ 2018-07-19 21:45 UTC (permalink / raw)
To: Stefan Beller; +Cc: git, Jeff King, primetheus
> On Jul 19, 2018, at 11:19 PM, Stefan Beller <sbeller@google.com> wrote:
>
> On Thu, Jul 19, 2018 at 2:02 PM Lars Schneider <larsxschneider@gmail.com> wrote:
>>
>> Hi,
>>
>> I have a blob hash and I would like to know what commit referenced
>> this blob first in a given Git repo.
>
> git describe <blob>
>
> If the given object refers to a blob, it will be described as
> <commit-ish>:<path>,
> such that the blob can be found at <path> in the <commit-ish>, which itself
> describes the first commit in which this blob occurs in a reverse
> revision walk from HEAD.
>
> Since
> 644eb60bd01 (builtin/describe.c: describe a blob, 2017-11-15)
> (included first in 2.16.0
>
> You're welcome,
> Stefan
Awesome! Thank you very much :-)
- Lars
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Find commit that referenced a blob first
2018-07-19 21:19 ` Stefan Beller
2018-07-19 21:45 ` Lars Schneider
@ 2018-07-19 21:47 ` Jeff King
2018-07-19 22:38 ` Junio C Hamano
2 siblings, 0 replies; 6+ messages in thread
From: Jeff King @ 2018-07-19 21:47 UTC (permalink / raw)
To: Stefan Beller; +Cc: Lars Schneider, git, primetheus
On Thu, Jul 19, 2018 at 02:19:34PM -0700, Stefan Beller wrote:
> > I have a blob hash and I would like to know what commit referenced
> > this blob first in a given Git repo.
>
> git describe <blob>
>
> If the given object refers to a blob, it will be described as
> <commit-ish>:<path>,
> such that the blob can be found at <path> in the <commit-ish>, which itself
> describes the first commit in which this blob occurs in a reverse
> revision walk from HEAD.
>
> Since
> 644eb60bd01 (builtin/describe.c: describe a blob, 2017-11-15)
> (included first in 2.16.0
Hmm.
$ git describe cfbc47ee2d
fatal: No tags can describe '83adac3c57ad8cd2c8d44b525414b949950e316d'.
Try --always, or create some tags.
$ git describe --always cfbc47ee2d
83adac3c57:checkout-cache.c
That first output confused me for a moment. We can't produce a nice
descriptive name for the commit in question, so we punt on the whole
thing.
Anyway. I have found your diff --find-object to be more useful in
practice. I.e.:
git log --find-object=cfbc47ee2d
because I usually care less about a succinct name, and more about
digging into the history (so adding "-p", etc).
-Peff
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Find commit that referenced a blob first
2018-07-19 21:19 ` Stefan Beller
2018-07-19 21:45 ` Lars Schneider
2018-07-19 21:47 ` Jeff King
@ 2018-07-19 22:38 ` Junio C Hamano
2018-07-19 22:45 ` Stefan Beller
2 siblings, 1 reply; 6+ messages in thread
From: Junio C Hamano @ 2018-07-19 22:38 UTC (permalink / raw)
To: Stefan Beller; +Cc: Lars Schneider, git, Jeff King, primetheus
Stefan Beller <sbeller@google.com> writes:
> On Thu, Jul 19, 2018 at 2:02 PM Lars Schneider <larsxschneider@gmail.com> wrote:
>>
>> Hi,
>>
>> I have a blob hash and I would like to know what commit referenced
>> this blob first in a given Git repo.
>
> git describe <blob>
>
> If the given object refers to a blob, it will be described as
> <commit-ish>:<path>,
> such that the blob can be found at <path> in the <commit-ish>, which itself
> describes the first commit in which this blob occurs in a reverse
> revision walk from HEAD.
You walk from the latest to earlier commit (because there by
definition can be is no reverse pointer from older to newer commit),
and see if it has the blob, and stop when you find one. Wouldn't it
generally find the most recent use, not the earliest use as Lars
seems to want?
>
> Since
> 644eb60bd01 (builtin/describe.c: describe a blob, 2017-11-15)
> (included first in 2.16.0
>
> You're welcome,
> Stefan
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Find commit that referenced a blob first
2018-07-19 22:38 ` Junio C Hamano
@ 2018-07-19 22:45 ` Stefan Beller
0 siblings, 0 replies; 6+ messages in thread
From: Stefan Beller @ 2018-07-19 22:45 UTC (permalink / raw)
To: Junio C Hamano; +Cc: Lars Schneider, git, Jeff King, primetheus
On Thu, Jul 19, 2018 at 3:38 PM Junio C Hamano <gitster@pobox.com> wrote:
> > If the given object refers to a blob, it will be described as
> > <commit-ish>:<path>,
> > such that the blob can be found at <path> in the <commit-ish>, which itself
> > describes the first commit in which this blob occurs in a reverse
> > revision walk from HEAD.
>
> You walk from the latest to earlier commit (because there by
> definition can be is no reverse pointer from older to newer commit),
but a "reverse walk from HEAD" produces the commits to us in an order
as if we were walking from earlier to latest?
^ permalink raw reply [flat|nested] 6+ messages in thread