Check if current directory is a Git repository

问题

I am writing a series of scripts for Git management in zsh.

How do I check if the current directory is a Git repository? (When I'm not in a Git repo, I don't want to execute a bunch of commands and get a bunch of fatal: Not a git repository responses).

回答1:

Copied from the bash completion file the following is a naive way to do it

# Copyright (C) 2006,2007 Shawn O. Pearce <spearce@spearce.org>
# Conceptually based on gitcompletion (http://gitweb.hawaga.org.uk/).
# Distributed under the GNU General Public License, version 2.0.

if [ -d .git ]; then
  echo .git;
else
  git rev-parse --git-dir 2> /dev/null;
fi;

You could either wrap that in a function or use it in a script.

Condensed into a one line condition suitable for bash or zsh

[ -d .git ] || git rev-parse --git-dir > /dev/null 2>&1

回答2:

You can use:

git rev-parse --is-inside-work-tree

Which will print 'true' if you are in a git repos working tree.

Note that it still returns output to STDERR if you are outside of a git repo (and does not print 'false').

Taken from this answer: https://stackoverflow.com/a/2044714/12983

回答3:

Use git rev-parse --git-dir

if git rev-parse --git-dir > /dev/null 2>&1; then
  : # This is a valid git repository (but the current working
    # directory may not be the top level.
    # Check the output of the git rev-parse command if you care)
else
  : # this is not a git repository
fi

回答4:

Or you could do this:

inside_git_repo="$(git rev-parse --is-inside-work-tree 2>/dev/null)"

if [ "$inside_git_repo" ]; then
  echo "inside git repo"
else
  echo "not in git repo"
fi

回答5:

Not sure if there is a publicly accessible/documented way to do this (there are some internal git functions which you can use/abuse in the git source itself)

You could do something like;

if ! git ls-files >& /dev/null; then
  echo "not in git"
fi

回答6:

Another solution is to check for the command's exit code.

git rev-parse 2> /dev/null; [ $? == 0 ] && echo 1

This will print 1 if you're in a git repository folder.

回答7:

Based on @Alex Cory's answer:

[ "$(git rev-parse --is-inside-work-tree 2>/dev/null)" == "true" ]

doesn't contain any redundant operations and works in -e mode.

As @go2null noted, this will not work in a bare repo. If you want to work with a bare repo for whatever reason, you can just check for git rev-parse succeeding, ignoring its output.
- I don't consider this a drawback because the above line is indended for scripting, and virtually all git commands are only valid inside a worktree. So for scripting purposes, you're most likely interested in being not just inside a "git repo" but inside a worktree.

回答8:

this works for me. You still get the errors but they're easy enough to suppress. it also works from within subfolders!

git status >/dev/null 2>&1 && echo Hello World!

You can put this in an if then statement if you need to conditionally do more.

回答9:

You can add to or replace your $PS1 in your zshrc with one or another git-prompt tools. This way you can be conveniently apprised of whether you're in a git repo and the state of the repo is in.

回答10:

This answer provides a sample POSIX shell function and a usage example to complement @jabbie's answer.

is_inside_git_repo() {
    git rev-parse --is-inside-work-tree >/dev/null 2>&1
}

git returns errorlevel 0 if it is inside a git repository, else it returns errorlevel 128. (It also returns true or false if it is inside a git repository.)

Usage example

for repo in *; do
    # skip files
    [ -d "$repo" ] || continue
    # run commands in subshell so each loop starts in the current dir
    (
        cd "$repo"
        # skip plain directories
        is_inside_git_repo || continue
        printf '== %s ==\n' "$repo"
        git remote update --prune 'origin' # example command
        # other commands here
    )
done

回答11:

# check if git repo

if [ $(git rev-parse --is-inside-work-tree) = true ]; then
    echo "yes, is a git repo"
    git pull
else
    echo "no, is not a git repo"
    git clone url --depth 1
fi

回答12:

Why not using exit codes? If a git repository exists in the current directory, then git branch and git tag commands return exit code of 0; otherwise, a non-zero exit code will be returned. This way, you can determine if a git repository exist or not. Simply, you can run:

git tag > /dev/null 2>&1 && [ $? -eq 0 ]

Advantage: Flexibe. It works for both bare and non-bare repositories, and in sh, zsh and bash.

Explanation

git tag: Getting tags of the repository to determine if exists or not.
> /dev/null 2>&1: Preventing from printing anything, including normal and error outputs.
[ $? -eq 0 ]: Check if the previous command returned with exit code 0 or not. As you may know, every non-zero exit means something bad happened. $? gets the exit code of the previous command, and [, -eq and ] perform the comparison.

As an example, you can create a file named check-git-repo with the following contents, make it executable and run it:

#!/bin/sh

if git tag > /dev/null 2>&1 && [ $? -eq 0 ]; then
    echo "Repository exists!";
else
    echo "No repository here.";
fi

回答13:

! git rev-parse --is-inside-work-tree >/dev/null 2>&1 || { 
  printf '%s\n\n' "GIT repository detected." && git status
}

The ! negates so even if you run this in a directory that is not a git repo it will not give you some fatal errors

The >/dev/null 2>&1 sends the messages to /dev/null since you're just after the exit status. The {} are for command groupings so all commands after the || will run if the git rev-parse succeeded since we use a ! which negated the exit status of git rev-parse. The printf is just to print some message and git status to print the status of the repo.

Wrap it in a function or put it in a script. Hope this helps

来源：https://stackoverflow.com/questions/2180270/check-if-current-directory-is-a-git-repository

标签

git

zsh