git crash course

A really short introduction to git for my PhD fellas.

First, TryGit

Clone something

There are two ways to start to work in a git repository.

  • git clone https://github.com/some_user/some_repo.git to download a project into a new directory some_repo.
  • git init to make the corrent directory a git repository.

Go ahead and clone a project of interest.

Working locally

git local workflow

Remember! you can always see the current state and the staging / unstaging commands with git status, so don't try to memorize them.

When you are satisfied with the changes commit them:

git commit -m "an informatice message describing your change"

Explore

git log  # see the history
git diff  # see the unstaged changes
git diff --staged  # see the staged changes
git show <COMMIT_HASH>  # see the changes in a commit

Collaborating through GitHub

GitHub is a place to share and collaborate on git repositories.

Your local git repository can be "linked" to remote repositories. To see them run git remote. If you cloned an existing repository you should see one remote, called origin, in the list. Otherwise, create a new GitHub repository and add it as a remote with:

git remote add origin https://github.com/you/your_repo.git

pull

To get the latest changes (commits) from your remote run:

git pull origin master

push

To update the remote with your changes (commits) run:

git push origin master

Remember! Always pull before you push to avoid unnecessary conflicts.

git Austin Powers meme

A simple but complete workflow

Assuming that you already have a local repository with a remote (called origin) that you can push code to:

git pull origin master         # to get the latest changes
# work work work...
git status                     # to see all of the changes you did
git diff                       # optional but handy
git add FILE_WITH_CHANGES      # repeat as necessary
git commit -m "your message"   # commit the changes to the repository
git push origin master         # to upload your changes

More info and resources

  • Branches are an important concept in git. Learn it!
  • Pro Git book: lots of info, sometime too verbose.