Notes about Git

Manuals

• Crash Course: http://git.or.cz/course/svn.html
• User Manual for Git: http://www.kernel.org/pub/software/scm/git/docs/user-manual.html
• Very good article about how to work with branches http://nvie.com/git-model

Issues

Branches for development of OpenPetra

• • in my own words: working with branches is central to git; some people make a branch for each feature they are working on; I think each developer should have his own branch (or even several if working on different OS or machines), and merge to master as often as possible; you can have local and remote branches; it would make sense to create a local branch, and then push it to the server creating a remote branch.
  • http://sites.google.com/a/insoshi.com/insoshi-guides/Git-Guides/working-on-a-local-development-branch
  • http://sites.google.com/a/insoshi.com/insoshi-guides/Git-Guides/pushing-up-your-changes
  • http://blog.hasmanythrough.com/2008/12/18/agile-git-and-the-story-branch-pattern
  • http://sites.google.com/a/insoshi.com/insoshi-guides/Git-Guides/merge-vs-rebase

# first make sure we are on the main branch
git checkout master
# create a local branch that is called mynewbranch
git branch mynewbranch
# switch to that branch
git checkout mynewbranch
# create the branch also on the remote repository
git push ssh://..../openpetraorg/openpetraorg/ mynewbranch:refs/heads/mynewbranch
# change config so that future git push will go into correct remote branch
git config branch.mynewbranch.remote ssh://..../openpetraorg/openpetraorg
git config branch.mynewbranch.merge refs/heads/mynewbranch
# push changes in local branch to remote branch
git push

# make your changes in the branch, commit to branch
git commit -a
# push branch to remote branch
git push
# switch to master
git checkout master
# get latest from master
git pull
# merge from branch
git merge mynewbranch
# push to master
git push
# switch to branch again
git checkout mynewbranch

todo: get the changes from HEAD into your local branch 

Branches for adjustments for other organisations

benefit: you can make modifications to the UINavigation and the base data structure etc. and even to the screen en.yml files

I have this setup for one organisation:

• created on my own server a git repository with an anonymous clone from the sourceforge openpetraorg git repository.
• cloned my own repository to my workstation
• on the workstation: create a branch on the repository, switch to the branch, modify a file, commit changes locally, push it not to master, but enter the name of your branch
  • dangerous: after you have created the branch on the server, NEVER switch to the remote branch: commits to that undefined branch will be eventually be lost at the next switch between branches, and you cannot push from that undefined branch. First create a local branch, and then pull from the remote branch into your local branch!
• on the workstation, on a fresh git pull: git checkout -b branchname origin/BRANCHNAME
• you can pull on your server from the sf repository, to follow the changes in the main repository, and merge from master into your branch
  • pull from server: do this on the command line on your server, current branch is master, git pull
  • merge from master: on my workstation, pull origin/master, which will automatically merge? otherwise merge from remotes/origin/master; then push to my branch on my server
• you should create patches of your own development and post them in the OpenPetra forum so that all other users can benefit from your improvements

line feed issues

• • see also http://stackoverflow.com/questions/861995/is-it-possible-for-git-merge-to-ignore-line-ending-differences
  • see also http://stackoverflow.com/questions/1011985/line-endings-messed-up-in-git-how-to-track-changes-from-another-branch-after-a
  • http://git.or.cz/gitwiki/GitSvnComparsion suggests that on Windows in the config file in .git, you should set "core.autocrlf = true so that text files are automatically checked out with CRLF and checked in as LF".
  • see also discussion at http://code.google.com/p/msysgit/issues/detail?id=21

delete a remote branch

• if a remote branch is not needed anymore, and everything has merged into master, we don't want to see the branch anymore

git push ssh://MYUSERNAME@openpetraorg.git.sourceforge.net/gitroot/openpetraorg/openpetraorg :refs/heads/MYBRANCHTODELETE

selective merge

• see also discussion here:
  • http://stackoverflow.com/questions/449541/how-do-you-merge-selective-files-with-git-merge

• http://jasonrudolph.com/blog/2009/02/25/git-tip-how-to-merge-specific-files-from-another-branch/
  • git checkout
• http://tech.efreedom.com/Question/1-449541/How-do-you-merge-selective-files-with-git-merge
  • git cherry pick http://www.kernel.org/pub/software/scm/git/docs/git-cherry-pick.html
  • or splitting one commit into several commits with rebase

• with tortoiseGit: show log, right click on commit, cherry pick
  • see also http://code.google.com/p/tortoisegit/issues/detail?id=285

TortoiseGit

For development on Windows, we recommend TortoiseGit

Git Bash

• You need to add each changed file before you commit. Otherwise that file will not be part of the next commit.
• If you added too many files by accident, and you want to lose them completely: (use this carefully with -f) git rm . -r
  • even better: to unstage: git reset HEAD <file>...
• undo all local changes: git checkout -f
• to revert a single file: use git checkout filename (see http://norbauer.com/notebooks/code/notes/git-revert-reset-a-single-file)
• to ignore eg. *.bak files, create a file .gitignore and add the files; eg see OpenPetra/csharp/.gitignore