GIT
Git is a powerful source-control system that lets you manage your projects, have a backup and history on hand at all times, and share and collaborate with others. Git is not just about Github, you can use it locally or privately to track your own code, documents, or anything really.
Essentials
Working with an existing repo:
git clone git://url # checkout a copy
git branch -a # lists branches
git checkout origin/branch_name # checkout specific branch
git diff # show local changes
git status # show current situation
git log # list recent changes
Add changes/new file(s), commit, then push:
git add .
git commit -am 'my log message'
git push
after you add a files, you can do a diff of staging area vs HEAD, before you commit:
$ git diff --cached
to delete a branch
$ git branch -d branch-name # local branch
$ git push origin --delete <branchName> # @ github!
Dealing with problems
to fix the previous log message (any you didnt push yet)
$ git commit --amend
To remove a file that is staged (ready for commit), use –cached. Note this does not remove the actual file on disk, it just removes it from the staging area.
$ git rm --cached file
Note that although git add is recursive, git rm is not, so to remove a whole directory:
$ git rm -r --cached some/directory/here
to undo a git add that was not yet committed:
$ git reset .
or just reset everything back to the last commit:
$ git reset --hard
or in a really messed up situation, with lots of untracked files or changes, you may need to:
$ git clean -f -d
to get rid of a bunch of changes
$ git stash
$ git stash drop
after a rejected push, do:
$ git remote update && git rebase origin/master
to revert a merge or large commit that was NOT yet pushed:
$ git co master
Switched to branch 'master'
Your branch is ahead of 'origin/master' by 396 commits.
$ git reset --soft HEAD~396
$ git st
# On branch master
# Your branch is behind 'origin/master' by 648 commits, and can be fast-forwarded.
#
# Changes to be committed:
# ... (lots of stuff)...
$ git reset --hard
HEAD is now at xxxx etc
$ git st
# On branch master
# Your branch is behind 'origin/master' by 648 commits, and can be fast-forwarded.
# ...
$ git pull
# ... (lots of stuff)...
$ git st
# ... (clean!)...
To totally revert a branch
$ git branch -D master
$ git checkout master
Tips
To automatically choose a remote branch for git push and git pull, edit .git/config:
[branch "master"]
remote = origin
merge = refs/heads/master
When you first push a branch, enable tracking with:
$ git push -u origin master
To do a rebase by default with git pull, add this to the branch in .git/config:
[branch "master"]
rebase = true
do garbage collection, save disk space (for when you’ve been tracking big files):
$ git gc
list remotes
$ git remote -v
to see the diff of previous commits vs working copy:
$ git diff @{1} # <-- last commit
$ git diff @{2} # <-- last 2 commits
$ git diff @{10} # <-- last 10 commits
$ git diff eb54dc40 # <-- part of the commit SHA
Perhaps the easiest way to catch up with what changed is to have git show you the diffs, commit-by-commit:
$ git log -p
When committing a large change, you may want to separate the commits. By doing a patch commit, where git will ask you about each change and you can choose to add, skip or delete them one-by-one:
$ git commit -p
By default, when you do a git push, it pushes all branches. You can disable this with:
$ git config --global push.default tracking