On Tue, Jul 9, 2019 at 4:13 PM Elijah Newren <[email protected]> wrote:
>
> Hi John,
>
> On Tue, Jul 9, 2019 at 3:57 PM McRoberts, John <[email protected]> wrote:
> >
> > I am responsible for generating a list of all files changed between two
> > successive releases of software. I was using 'git diff' but have run into a
> > problem.
> >
> > Consider the following situation: A development branch comes off of commit A
> > and files are changed three times. A tag (REL1) is placed on the third
> > commit. Then the branch is merged back to master. At this point, master's
> > HEAD is at C (and it remains there). Two development branches are created
> > off of master, the first of which is not important here. In the second one,
> > there are files changed and a tag (REL2) applied.
> >
> >
> > ---------------------[I]
> >
> > / {dev branch}
> >
> > /
> >
> > /
> > {master branch}
> > /
> > [A] ---------------------------------[B]------------------------------->[C]
> > master <HEAD>
> > \ filelist 6 / \
> > \ /
> > \
> > \ /
> > \
> > \ /
> > \
> > \ {development branch} /
> > \
> > \------->[D]----------------------->[E]-------------------[F]
> > \------[G]--------[H]
> > REL1
> > REL2
> > fileset 1 fileset 2 fileset 3
> > fileset 4 fileset 5
> >
> > At this point, I run
> > 'git diff -m --first-parent --pretty=fuller --decorate=short
> > --name-only REL2..REL2'
>
> Wow, we really, really need to throw errors and warnings when people
> use crazy range operators with diff.[1][2] What version of git are
> you using that accepts --decorate=short as an argument to `git diff`?
> And why in the world does git diff accept --first-parent or
> --pretty=fuller?!? That's insane for git-diff to swallow that.
> (#leftoverbits?) Also, I think you meant `REL1` one of the two times
> you wrote `REL2`, which makes me suspect you may have done some
> copy-edit-paste and didn't try this actual command.
>
> > I expect to see only filesets 4 and 5 listed. I also see filesets 1, 2 and
> > 3 showing up. This means that the git diff command is showing files that,in
> > fact, did not change between the two tags. By the way, I verified with a
> > file by file comparison that under REL2 and REL1, the files represented by
> > filesets 1, 2 and 3 had identical contents.
>
> From your description, I assume you actually ran something like
> git diff --name-only REL1..REL2
Did you mean REL1...REL2 (3 dots)? 2 dots (REL1..REL2) is identical to
no dots (REL1 REL2), per the documentation for "git diff":
git diff [<options>] <commit> <commit> [--] [<path>...]
This is to view the changes between two arbitrary <commit>.
git diff [<options>] <commit>..<commit> [--] [<path>...]
This is synonymous to the previous form. If <commit> on one
side is omitted, it will have the same effect
as using HEAD instead.
(Forgive me if I'm mistaken here!)
>
> which compares REL2 to the merge base of REL1 and REL2 (yes, this is
> totally counter-intuitive to a large percentage of the git userbase,
> but it is well documented and hard to change). Also from your
> description, what you seem to want is
> git diff --name-only REL1 REL2
>
> since you want to compare the two endpoints. Does that help get what you
> want?
>
> Hope that helps,
> Elijah
>
> [1]
> https://public-inbox.org/git/CABPp-BECj___HneAYviE3SB=wU6OTcBi3S=+un1sp6l4wj7...@mail.gmail.com/
> [2]
> https://public-inbox.org/git/cabpp-bgg_isx3qmc-j4fov97v9nnatfxzgmrm3wfrgugoth...@mail.gmail.com/
