Re: Understanding a recent commit in emacs-25 branch [ed19f2]

[Alan Mackenzie <acm@muc.de>]

Hello, Kaushal.

That massive commit happened because of git.  I attempted a 'git pull'
prior to making a (moderately small) commit.  There was a one-letter
typo in one of my existing files (which I think had been committed).
Because of that, git failed to merge in all the stuff which it had just
fetched from savannah, instead prompting me to do a manual merge, which
I then did.

This is a problem with SCM systems.  There is no "undo" for a lot of
operations.  If I had been aware of what was happening, I might have
been able to adjust my copy of the repository somehow so as to avoid
that large merge.

It would also be nice if such "pseudo merges" could be handled locally,
rather than being pushed back to the remote repository, causing
confusion.

On Fri, Apr 01, 2016 at 01:43:16AM -0400, Kaushal Modi wrote:
> OK, I think I need some git education.

Me, too!

> There was one section in your commit (
> http://git.savannah.gnu.org/cgit/emacs.git/diff/lisp/isearch.el?h=emacs-25&id=ed19f207449c43f7f08285ada87ae7a46c61c8d1
> ) which was already committed earlier (
> http://git.savannah.gnu.org/cgit/emacs.git/commit/lisp/isearch.el?h=emacs-25&id=91e667692ba1362ca1334b8d58fd16c305ad5e2a
> ). As I am familiar with that single commit, I know that they are identical.

> Also I noted that your commit has a repeat of all the backquote/straight
> quote changes in NEWS that happened recently.

> But without this prior knowledge, how can one separate these duplicate
> commits from the commits that actually are new?
> Also, what is the reason for such duplicate commits happening?

See above.

> Apologies for this git 101 question here. Please forward me to a resource,
> if available, where I can understand such mega commits.

No apologies needed.  git is a complicated, difficult to learn system.

> Thanks.

-- 
Alan Mackenzie (Nuremberg, Germany).