Over the years I've tried and used many different git clients. SourceTree, GitUp, Gitk, Magit, to name a few. Magit (a Git client build into Emacs) is the one I still use the most, but over the years I've more and more moved towards plain git on the terminal for most of my daily activities. However, one thing always bugged me: If I have an output from git status (say the following one):

On branch master
Your branch is up to date with 'origin/master'.

Changes to be committed:
  (use "git reset HEAD <file>..." to unstage)

        modified:   Readme.md

Changes not staged for commit:
  (use "git add <file>..." to update what will be committed)
  (use "git checkout -- <file>..." to discard changes in working directory)

        modified:   component_stats.db
        modified:   q.sql

Untracked files:
  (use "git add <file>..." to include in what will be committed)

        documentation/README.md
        api_design/design_draft.md

Then if I want to add the two untracked files and the q.sql to the index (in order to commit them) I'd have to write:

git add documentation/README.md
git add pi_design/design_draft.md
git add q.sql

That's a lot of typing. Usually I go about copy pasting with the mouse. That also takes forever. Surely using a git GUI tool (like SourceTree) is much faster but as I don't need it for any of the other tasks I usually do, I'd need to start it first, which also takes forever. What I envisioned was an easy way to add, stage, unstage files in the git index, workspace and untracked files. Bonus points for also allowing git checkout -- to remove changes to a specific file.

I know there're tools for that (such as tig) but I wanted something that only did one thing, status management. No logging, no pushing or pulling, etc. This felt to me like a great opportunity to write a small scale C project, something I hadn't done for at least more than 10 years.

This is how gitsi was born. Have a look at the project if you're interested, it offers a nice handful of features such as all of the above plus: VIM Keybindings, filtering, diffing, interactive git add and more.

Here's a short video that shows it in action

As a iOS developer I've had my fair share of Objective-C, however all the nice abstractions that Apple put in place actually mean that usually I don't really touch C code. So, writing something bigger in C was really interesting when comparing it to developing something in Swift (doh, obviously).

It relies on two libraries:

• libgit2: The interface to git. Interestingly git (the commandline tool) and libgit2 are separate entities. Meaning git does not use libgit. This means that for some things that git does, there is no easy equivalent in libgit. This makes some things very hard.
• ncurses: This is the library to use when developing TUI (terminal UI) applications. It allows you to move the cursor around in the terminal, color it, draw windows, etc.

Working on a project like this from Xcode works surprisingly well. I set up an Xcode project, added the required libraries (ncurses and libgit) imported the main.c file and I could compile it. Debugging was a wee bit more work. Since Xcode can't run ncurses executables (i.e. it can't run them in a terminal) we have to tell Xcode to compile the app and then wait for the process to start and then to attach to it. After that, I can head to a terminal and run the just-compiled app and then Xcode will attach to it and all the breakpoints etc work. It is a wee bit more cumbersome but works fine. I had to introduce a particular command line flag though that makes sure that attaching via Xcode doesn't break things.

There're no tests. Yet. I've started on the necessary prerequisites to run integration tests but I wanted to release it first. The idea is to start the binary in a special mode and give it a string of tasks (i.e. go down 2 lines, do a git add, go up one line, etc) and then make sure that the end result is what's expected.

This was a fun project, but now I'm also done with C for the rest of this year (except for small additions to gitsi, of course). I'm already longing to do something in Swift or Rust again.