Re: Undo last commit?

Mike [off-list ref] writes:

Hi fellow gitters,

I have performed a 'git commit' on all 'added' files by mistake and
now I want to undo this commit to return to the original state. Here's
a more detailed description:


1. I did a 'git status' and there were files which I had 'added' ready
for a commit. There were also some changes that had not been 'added'
yet. See below:

% git status
# On branch master
# Your branch is ahead of 'origin/master' by 7 commits.
#
# Changes to be committed:
#   (use "git reset HEAD <file>..." to unstage)
#
#	modified:   cgi-bin/example1.php
#	modified:   cgi-bin/example2.php
#	modified:   example3.php
#
# Changed but not updated:
#   (use "git add <file>..." to update what will be committed)
#   (use "git checkout -- <file>..." to discard changes in working directory)
#
#	modified:   cgi-bin/example4.php
#	modified:   example5.php
#


2. I accidentally did a commit for ALL files because I forgot to
specify the filename at the end of the commit.
e.g. instead of 'commit -m "commit message" example3.php' I did
'commit -m "commit message"'.

You committed all staged changes (i.e. only those on "Changes to be
committed" list), not all changes; for that you would need to use '-a'
option to git commit.

BTW. why are you using '-m' option?
 

3. I googled the problem and it seems everyone has a different way of
doing this. (Maybe git is too confusing if everyone has different
methods that all work slightly differently!?). Anyway I executed this
command:

% git commit --amend

You could simply use

  % git commit --amend -m "commit message" example3.php

The `--amend` just means to fix (redo) last commit.

But I aborted this by exiting my text editor.

O.K.

4. I then tried:

% git reset --hard HEAD~1

Errr... here you screwed up.  This reset state of you working area to
the state at last commit, removing all your changes to tracked files.

5. However now when I do a 'git status' none of the files that were
original listed are there. A git status now gives this:

# On branch master
# Your branch is ahead of 'origin/master' by 7 commits.
#
nothing to commit (working directory clean)


Any ideas how to rectify this issue? I presume the 'git commit
--amend' just changes the commit message? I daren't try anything else
myself in case I make matters worse.

You lost your changes to files on "Changed but not updated" list,
i.e. cgi-bin/example4.php and example5.php.

What you can do is go back to your last commit (the errorneous one) by
using

  $ git reset --keep HEAD@{1}

Which means reset to last state (before 'git reset --hard HEAD~1'; you
can check it with "git reflog" or "git log -g"), keeping your local
changes (if you used '--keep' not '--hard' then you wouldn't loose
your changes).

Then redo this commit like you wanted to

  $ git commit --amend -m "commit message" example3.php

Or better

  $ git commit --amend -v example3.php

To check if you are committing correct changes.

...................

Alternatively check out state of example3.php from last made commit:

  $ git checkout HEAD@{1} -- example3.php

Do your commit

  $ git commit -m "commit message" example3.php

Get state of other files that you accidentally comitted from next to
last state of HEAD:

  $ git checkout HEAD@{2} -- cgi-bin/example1.php cgi-bin/example2.php

Unfortunately changes to cgi-bin/example4.php and example5.php are
lost.

-- 
Jakub Narebski
Poland
ShadeHawk on #git