gitHUD: An HTML repository from pkernevez

As you might have guessed from its name, gitHUD is a heads up display for the command line that will show git information

Note: this example is taken from the iTerm2 OSX terminal, with custom colors from the Solarized Dark theme

Why gitHUD?
Install
Setup
ZSH
Configuration
Benefits
Benchmarks
Thanks

Why gitHUD?

I was really psyched a few months ago by git-radar. Git-radar does the exact same thing as gitHUD, but is implemented in shell. While I had a great time using it for a while, I realized that on my particular setup, git-radar was introducing a visible delay (200ms, too long for me) in the displaying of my prompt.

At that time, I was looking for an exercise to implement in Haskell, so that's how I created gitHUD

Install

Whatever the way you install gitHUD, don't forget to complete the Setup

Mac OSX with brew

link my tap

brew tap gbataille/homebrew-gba

install githud

brew install githud

With Cabal

gitHUD is available on hackage. Therefore just get it as usual

cabal install gitHUD

With stack

gitHUD is available on hackage, but not in the stack list of curated packages. to install it with stack, you need to add it to the extra-deps in your stack.yml file

extra-deps:
- gitHUD-1.0.0.0

then you can run

stack install gitHUD

From sources

Get the source
Compile them (haskell)

Setup

If you simply call the githud executable, you'll get a short status of your repository. It's meant to be called each time you display your prompt. Therefore you want to put it in your PS1 env variable.

For example, in my .bashrc file, with the executable at /usr/local/bin/gitHUD

export PS1="\[\033[0;37m\][\A]\[\033[0m\] \[\033[0;36m\]\u\[\033[0m\]
\W\[\033[0;32m\]\$(/usr/local/bin/gitHUD)\[\033[0m\]\$ "

ZSH

ZSH has some fancy way of managing prompt when you do things like autocompletion and the like. For that it needs to know the size of the prompt. Special characters used to express the color of the prompt need to be surrounded by special markup for them not to be counted.

To make it work with ZSH, add a "zsh" parameter:

gitHUD zsh

Invoking it from the command line will show you those %{ character.

Putting it together in my .zshrc, I have the following PROMPT variable with the executable at /usr/local/bin/gitHUD

export PROMPT=%{$fg_bold[white]%}%T%{$reset_color%}%{$fg[cyan]%} %n%{$reset_color%}
%{$fg_bold[green]%}$(shorter_path)%{$reset_color%} $(/usr/local/bin/gitHUD zsh)%{$(virtualenv_info)%}%(?,,%{${fg_bold[blue]}%}[%?]%{$reset_color%} )$ '

Fish

Add this code to your config.fish file.

function fish_prompt
  set_color white
  echo -n [(date "+%H:%M")]
  set_color cyan
  echo -n (whoami):
  set_color yellow
  echo -n (prompt_pwd)
  set_color $fish_color_cwd
  echo -n (/usr/local/bin/gitHUD)
  set_color normal
  echo -n "> "
end

Configuration

The prompt format is nicely configurable. The defaults give you the look and feel from the screenshot above, with a terminal configured with the Solarized Dark theme colors.

To change those colors, or the markers used in the prompt:

Copy the .githudrc file from this repository into your home directory
Edit the file by uncommenting some fields and changing their values (instructions are enclosed in the file)

Benefits

gitHUD is fast (on my system, about twice as fast as git-radar, with exec times below 100ms)
gitHUD is easily maintainable through proper test coverage

The only downside compared to git-radar is that you need to compile it on your platform, as opposed to being just shell.

On Mac, it's now easy since I packaged it as a brew bottle. For Linux, I'm waiting for contributions to put it in RPM or DEB packages :)

Benchmarks

So of course, I wanted to check that whatever I was doing was useful. So I did a couple of benchmark with the Haskell criterion library. It's based on my system and does not guarantee any performances but it gives you an idea of the improvements. Here goes:

git-radar - full shell implementation
gitHUD-syncIO - with normal IOs done one at a time
gitHUD-asyncIO - with IOs programmed asynchronously for better performance.

Here you can find the details

For information: I ran that on a Macbook Pro 13", 2014, fully boosted, running with iTerm 2, tmux, oh-my-zsh, inside a git repo with quite some information to parse

Thanks

Well, my thanks to git-radar for the great idea, and to guibou for the code reviews

pkernevez/gitHUD