Git

Latest git on CentOS

rpm -U http://pkgs.repoforge.org/rpmforge-release/rpmforge-release-0.5.3-1.el6.rf.x86_64.rpm
perl -pi.bak -e '!$first && s/(?<=enabled = )0/1/ && $first++' /etc/yum.repos.d/rpmforge.repo
yum install -y git

Merging a branch into master

Branch xyz needs to be merged into the master, and there are no conflicts, that is, xyz is ahead of master and not "behind":

$ git checkout xyz
$ git checkout master
$ git merge xyz master
$ git push
$ git branch -d xyz
$ git push origin --delete fix

If there are conflicts, you'll need to do more work:

$ git checkout xyz
$ git checkout master
$ git merge xyz master
Automated merge did not work.
$ git checkout xyz
# fix the conflicts so a merge will succeed
$ git commit -am 'fix merge conflicts from xyz to master'
$ git push
$ git merge xyz master
Trying simple merge with fix
Already up-to-date with master
Merge made by octopus.
$ git push
$ git branch -d fix
$ git push origin --delete fix

When you’ve prepared the index you want, use git commit to store it as a new commit. Use git status first to check the files involved, and git diff --cached to check the actual changes you’re applying. git diff alone shows any remaining unstaged changes (the difference between your working tree and the index); adding --cached (or the synonym --staged) shows the difference between the index and the last commit instead (i.e., the changes you’re about to make with this commit).

git reset --patch

With git reset --patch you can be even more specific, interactively selecting portions of your staged changes to unstage; it is the reverse of git add -p. See “Discarding Any Number of Commits” for other options.

1. Use git add (with various options) to stage a subset of your changes.
2. Run git stash --keep-index. This saves and undoes your outstanding, unstaged changes while leaving your staged changes in the index alone, resetting your working tree to match the index.
3. Examine this working tree state to make sure your selection of changes makes sense; build and test your software, for example.
4. Run git commit.
5. Now, use git stash pop to restore your remaining unstaged changes, and go back to step 1. Continue this process until you’ve committed all your changes, as confirmed by git status reporting “nothing to commit, working directory clean.”

git log --graph --oneline

*   f4dcb5b Merge remote branch 'origin/xyz' into xyz
|\
| *   2bc662f Merge remote branch 'origin/xyz' into xyz
| |\
| | * dfdac18 a new file
* | | f9d4689 a new file
|/ /
* | 7d482cf remove
* | 158f30e merge conflict
* | 3ddd434 cause conflict with xyz
|/
* 30f4b62 cleanup
* de74c31 fixed merge xyz to master
* 8224c26 fixed merge xyz to master

git config --global branch.autosetuprebase always

http://documentup.com/skwp/git-workflows-book http://chimera.labs.oreilly.com/books/1230000000561/index.html http://scottchacon.com/2011/08/31/github-flow.html http://git-scm.com/book/en/v2

git undo a commit

There doesn't seem to be an undo in git, but you can do this:

git reset --soft HEAD~1
git stash
git stash drop

Vagrant, Windows, and Git

If you are running Vagrant with Linux (guest) on Windows (host) and you want to share your git folder, you will need to turn off filemode checking. If you don't, Git will see all files as modified, because shared files get permissions 777, always.

To fix this, you'll need to:

git config --global core.filemode false

You'll need to run this on each of the shared repos:

cd <some-repo>
git config --local --unset core.filemode

You could potentially just set filemode to false on each of the repos, but it's easier to set it globally in Vagrant.

Git only tracks the execute bit so if you need to set that, you can do so explicitly:

git update-index --chmod=+x <some-file>