Git

Git is a free and open source distributed version control system designed to handle everything from small to very large projects with speed and efficiency.

I’m mostly sure that most engineers and developers are using git right now, but how well? Eh. Git is a massive and complex program that you don’t get good at overnight. And even if you git good, you might forget stuff. I forget stuff all the time, so I have a doc here to help me remember all the little things.

precommit hooks with `pre-commit`

I recently learned about pre-commit.

I found it when looking at ruff to see if it made sense for pre-commit hooks.

repos:
  - repo: https://github.com/charliermarsh/ruff-pre-commit
    rev: v0.0.107
    hooks:
      - id: ruff

I also found that Poetry had a page on pre-commit as well. Example:

hooks:
  - id: poetry-export
    args: ["-f", "requirements.txt"]
    verbose: true

nbdev also has pre commit hooks:

repos:
- repo: https://github.com/fastai/nbdev
  rev: 2.2.10
  hooks:
  - id: nbdev_clean
  - id: nbdev_export

creating git aliases

Thank you, person on stackoverflow

# shows the top level directory for the repo
git rev-parse --show-toplevel

# If you want to replicate the Mercurial command more directly, you can create an alias:
git config --global alias.root 'rev-parse --show-toplevel'

Ignore everything except a few files

Thanks to this stackoverflow thread.

You can use an optional prefix of !, which negates the pattern; any matching file excluded by a previous pattern will become included again. If a negated pattern matches, this will override lower precedence patterns sources.

# Ignore everything
*

# But not these files...
!.gitignore
!script.pl
!template.latex
# etc...

# ...even if they are in subdirectories
!*/

# if the files to be tracked are in subdirectories
!*/a/b/file1.txt
!*/a/b/c/*

Keeping all your dot files in a git repo

Thank you to probable robot for this.

Deletion

Deleting all commits before a certain date

Here’s a couple of stackoverflow answers that were pretty helpful:

Remove file from git

How Remove Files completely from git repository history

Ignore future revisions to a file

Per StackOverFlow:

# This will ignore changes to that file, both local and upstream
git update-index --skip-worktree fileyouwanttoignorefuturerevisionson

# when you decide to allow them again, use:
git update-index --no-skip-worktree fileyouwanttoignorefuturerevisionson

# You can get a list of files that are marked skipped with:
git ls-files -v . | grep ^S

Clean up old remote origin branches

git fetch --prune origin

Clean up local tags no longer present in remote repo

# list all local tags and delete them locally
git tag -l | xargs git tag -d

# fetch all the remote tags
git fetch --tags

Edit previous commits

Sign off on a previous commit (or range of previous commits)

# sign off on the past three commits
git rebase --signoff HEAD~3

Modify/Add/Remove file from previous commit

Here’s an example for adding a changed or new file to your previous commit

# add the file you forgot
git add testfile

# this amends the previous commit and does not edit the commit message
git commit --amend --no-edit

If this isn’t working, please ensure you spelled amend correctly. It only has one m. (I do this all the time)

Git

precommit hooks with pre-commit