DIY Git in Python

[macintux]

I really love the idea, but it's sent me down the Python packaging rabbit hole because the very first page's recommendation to use `python3 setup.py develop --user` doesn't work without some customization that I have yet to figure out.

First, it seems to (maybe?) work better with a venv running, which I didn't have. Ok, I can create one.

Next, `SetuptoolsDeprecationWarning: setup.py install is deprecated`, although I can live with that for now.

Next, I'm provided with a long list of ideas for how to enable `.pth` files, but https://setuptools.pypa.io/en/latest/deprecated/easy_install... strongly implies that `export PYTHONUSERBASE=`pwd`` prior to running setup should work. It doesn't.

Python, why does your ecosystem have to be so broken?

[PufPufPuf]

Python packaging is dead simple. You just define your package in requirements.txt, setup.py, setup.cfg, MANIFEST.in, pyproject.toml (although this one has two different ways to declare dependencies), and/or Pipfile. You then use pip, pipenv, virtualenv, venv, virtualenvwrapper, pyenv, pyenv-virtualenv, pyenv-virtualenvwrapper, poetry, and/or conda to install and manage the package.

[xcdzvyn]

It's almost surprising how far Python has come with the state pip is in; it's so rare to have any remotely sizeable software's dependencies install properly without some hacking.

[alex_lav]

Python packaging sucks. It's a big part of my job right now. To get various things to work, I've had to downgrade setuptools and manually install Cython.

[Too]

That instruction is not the recommended way.

To make it work, use a virtualenv, seriously always use a virtualenv. Then inside: pip install --editable ./

This has been the standard way to install packages since forever. Don’t know why author complicates it with lower level setuptools. This is the same message that deprecationwarning is giving btw.

[ibitto]

Two more Python implementations are mentioned in build-your-own-x [0].

- https://wyag.thb.lt

- https://benhoyt.com/writings/pygit/

[0]: https://github.com/codecrafters-io/build-your-own-x#build-yo...

[forgotpwd16]

Also codecrafters itself has build your own git course.

[jamesdutc]

Similar (but a far more limited implementation):

“Write a Git Client from Scratch in 25 Minutes”

https://youtu.be/xvzo_nV9PjU

[TuringNYC]

Putting aside git, i love the format and step-by-step teaching! You've done a better job at this than 99% of CS professors i've ever had. Thank you for doing this!

[evgpbfhnr]

This interface is downright awesome; I'd love something that takes a git repository and displays the commit message along with the diffs like this (might be how this works under the hood) If there's something usable like this I didn't know about, please say!

EDIT: from comment in the first page the author said it's custom typescript which isn't open-source yet, there's still hope :)

[microtherion]

This seems to be a similar idea to James Coglan's excellent book _Building Git_, which reimplemented Git in Ruby: https://shop.jcoglan.com/building-git/

[teleforce]

Nice tutorial on building Git with Python from scratch.

This book teach building Git from scratch with Ruby:

https://shop.jcoglan.com/building-git/

[tech234a]

Loosely related: Dulwich, a pure-Python Git implementation

https://github.com/jelmer/dulwich

[okasaki]

Probably fun to read and educational, but why in the world does the page use grey text on a grey background?

[anamexis]

It passes WCAG contrast guidelines just fine. It has a contrast ratio of 7.84, and the WCAG AAA standard requires 7.0.

I find it very readable.

[fiddlerwoaroof]

I implemented a read-only implementation of git here: https://github.com/fiddlerwoaroof/cl-git

It’s nearly complete, I just have to finish a couple annoying edge cases around delta compression.

[zserge]

A similar toy git in Go (but probably smaller and more limited): https://zserge.com/posts/git/

[aardvarkr]

This has been posted before but it’s incredibly well written and easy to follow. I had a blast with it last time it made the front page. Great post to reshare!

[asicsp]

Links:

https://news.ycombinator.com/item?id=28735425 (194 points | Oct 3, 2021 | 23 comments)

https://news.ycombinator.com/item?id=24517925 (309 points | Sept 18, 2020 | 30 comments)

[wild_pointer]

I took this tutorial and it vastly improved my git understanding, nicely done in both content and the way it's presented!