Detect git Directory with Bash

By  on  

One interesting aspect of working at Mozilla is that Firefox lives in a mercurial repository while several other projects live on GitHub in a git repository. While most focus on either Firefox or another project, I switch between both, leaving me running git commands inside the mercurial repository and hg commands inside git repos. It's a frustration that I've lived with for a while so I sought to find a unified way of completing common tasks.

The first step was learning to detect git from command line:

if git rev-parse --git-dir > /dev/null 2>&1; then
  # git repo!
else
  # NOT a git repo!
fi

The if statement above detects a git repository, the else means the current directory is not inside a git repo.

One frequent task is checking out master and pulling the latest code from upstream, so I create an alias to do just that:

master() {
  if git rev-parse --git-dir > /dev/null 2>&1; then
    git checkout master && git pull upstream master
  else
    hg pull && hg checkout "last(public())"
  fi
}

This alias will save me time and frustration moving forward, and I'm sure I'll find other aliases to create based on git detection!

Recent Features

  • By
    Regular Expressions for the Rest of Us

    Sooner or later you'll run across a regular expression. With their cryptic syntax, confusing documentation and massive learning curve, most developers settle for copying and pasting them from StackOverflow and hoping they work. But what if you could decode regular expressions and harness their power? In...

  • By
    5 More HTML5 APIs You Didn’t Know Existed

    The HTML5 revolution has provided us some awesome JavaScript and HTML APIs.  Some are APIs we knew we've needed for years, others are cutting edge mobile and desktop helpers.  Regardless of API strength or purpose, anything to help us better do our job is a...

Incredible Demos

Discussion

  1. bryanYangGaoFei

    shell is powerful tool !

  2. Very true! Multiple projects on different repositories can be frustrating, especially if you keep messing up on the commands. Can you tell in more detail how to create an alias in Git bash? I haven’t used it a lot so I am not very familiar with it.

  3. Thanks a lot, I test this to fool it by creating empty folder/.git/config file and it complaint that not a git repository.

    I usually use

    -f .git/config

    .

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!