Re: [PATCHv2 6/7] builtin/describe.c: describe a blob

From: Stefan Beller <sbeller@google.com>
Date: Nov 1, 2017, 17:59 UTC
Message-ID: <CAGZ79kZPNiNnSJd6CNYb7XkTVsT2ONLQLhwAQxt6_SPFTSwMcw@mail.gmail.com>
In-Reply-To: <alpine.DEB.2.21.1.1711011329300.6482@virtualbox>

Show 19 quoted lines

>> Does the code describe a9dbc3f12c as v2.15.0:GIT-VERSION-GEN, or
>> would it always be <commit>:<path>?
>
> As the blob is described using this function:
>
> static void process_object(struct object *obj, const char *path, void *data)
> {
>        struct process_commit_data *pcd = data;
>
>        if (!oidcmp(&pcd->looking_for, &obj->oid) && !pcd->dst->len) {
>                reset_revision_walk();
>                describe_commit(&pcd->current_commit, pcd->dst);
>                strbuf_addf(pcd->dst, ":%s", path);
>        }
> }
>
> i.e. as `describe_commit()` is used on the commit part, the answer to your
> question is: the former. I guess that is why Stefan wrote `commit-ish`
> instead of `commit` ;-)

$ ./git describe a9dbc3f12c warning: reflog of 'HEAD' references pruned commits v2.15.0-7-g980e40477f:GIT-VERSION-GEN

So as noted below, this output is less than ideal, but technically correct as v2.15.0-7-g980e40477f contains that blob as well (you don't have these; it is this very series consisting of 7 patches on top of 2.15, none of them touching GIT-VERSION-GEN, hence that blob stays intact.)

The way Junio asked, we actually may prefer the commit-ish to give that commit that introduced the blob for the first time, i.e. add the --reverse to the graph walking.