rouge8 / rug

A stripped-down version of Git, implemented in Rust

rug, a Git implementation in Rust

This is my implementation of Jit, from James Coglan's book Building Git.

Usage

Build the rug binary and add it to your PATH:

$ cargo build
$ export PATH=/path/to/rug/target/debug:$PATH

Switch to the directory you want to track using rug:

$ mkdir /tmp/rug-test && cd /tmp/rug-test
$ mkdir -p foo/bar

$ echo "hello" > hello.txt
$ echo "world" > foo/bar/world.txt

Finally, initialize a Git repo and create a commit:

$ rug init
$ rug add .

# Currently, this waits for your input. Type in your commit message
and hit Ctrl+D
$ rug commit

You should now be able to use Git to view the commit you just created:

git show

Other supported commands

rug status
rug status --porcelain

rug diff
rug diff --cached

rug branch foo HEAD~5

Gotchas with the rug repo

I use rug as the version-control system for the rug source-code. However, because all commands are not implemented yet, I've been using git for eg. pushing to Github.

This means sometimes you might have to hackily modify files in .git to bring it back into a state that rug finds acceptable. Here are some ways in which things can break:

1. Updating master after pulling from origin rug pull does not currently work.

   After running git fetch origin, copy the SHA from .git/refs/remotes/origin/master into .git/refs/heads/master:

   cp .git/refs/remotes/origin/master .git/refs/heads/master

2. rug doesn't understand packed objects

   Copy the packed object outside .git and unpack it:

   mkdir temp
   mv .git/objects/pack/pack-ab7ec7453bc7444032731b68f2c1fe06279bd017.pack temp/
   git unpack-objects < temp/pack-ab7ec7453bc7444032731b68f2c1fe06279bd017.pack