kb / Git

Delete the last n commits

git reset --hard HEAD~n

Move commits to another branch

First, actually make the branch you were supposed to use (but don’t switch to it).

git branch chores/fix-my-sins

Now the new branch points to the former HEAD of master (or whatever the wrong branch was). You’ll want to move the HEAD of the current branch back however many commits (let’s say 4).

Of course, if you do that you might lose uncommitted changes you’ve made, so that’s why --keep is a thing.

# Change 4 to however many mistakes/commits you managed to make
git reset --keep HEAD~4

Now go back to writing your crappy code, but in the right branch this time.

git checkout chores/fix-my-sins

Reset to remote HEAD

Alright so you gone and messed everything up and want to just go back to the way things were on your remote? Sure you could delete your local repository and re-clone like a chump or instead you could do this pro gamer move:

# Make sure you have an updated copy of whatever remote branch you want to reset to
git fetch origin master
# Reset
git reset --hard origin/master

Nuke a file

oopsie woopsie you just commited a fiwle with API keys or something
awh!! can’t just dewete the fwile in a commit because git has a histowy unu

This processes the history of every branch and tag, removing the file:

git filter-branch --force --index-filter \
  "git rm --cached --ignore-unmatch PATH-TO-FILE-TO-DELETE" \
  --prune-empty --tag-name-filter cat -- --all

--index-filter will rewrite the Git index without having to check out the entire tree, making it faster than --tree-filter
git rm tells Git to remove the file (plain rm works as well, but git rm lets you use --index-filter)
--cached tells git rm to only modify the Git index and to leave your working tree files untouched
--ignore-unmatch tells git rm not to complain if the file doesn’t exist in a commit
--prune-empty removes gross empty commits that can sometimes be generated
--tag-name-filter cat -- --all updates the tags you have

Force push your changes on all branches if everything looks right:

git push origin --force --tags

You’ll have to update tags separately:

git push origin --force --tags

Remember that your contributors will now have to rebase. Shame on you.

Find the .git folder

Useful for when your classmates aren’t paying attention in class, decide that they know git better than the professor teaching them git, and then they do an oopsie woopsie and make nested git repositories (that aren’t submodules). This usually ends up with them having an undesired repository active in their current working directory, and they want it to stop.

Find the .git directory for the undesired repository

git rev-parse --git-dir

Then delete it lol

rm -rf path/to/.git/

Or if you’re in a submodule but want its parent .git folder for some reason:

git rev-parse --show-superproject-working-tree

GitHub Atom feeds

GitHub allows you to watch repositories, which sends you notifications for new issues, pull requests, and releases. But what if you’d like notifications for each commit, or changes to just a directory or single file? GitHub publishes Atom feeds for several Git paths:

Commits to master: https://github.com/:owner/:repo/commits.atom
Commits to a branch: https://github.com/:owner/:repo/commits/:branch.atom
Commits to a file or folder: https://github.com/:owner/:repo/commits/path/to/file.atom

Private repositories only offer Atom feeds for commits to a branch, which you can find in the application/atom+xml link tag when viewing a branch in your browser.