How to tell git branch name from commit hash?

Question

I have a bash script which accepts a string of either a branch name (e.g., \"master\", or \"feature/foo\") or a commit hash (e.g. \"1234abcd\").

I have the repository c

Answer 1

As @VonC and @hek2mgl mentioned, this may not be a one or the other test. You could slightly modify your script to something like this (borrowed from this SO answer:

#!/bin/bash
commit_or_branch="$1"
cd /path/to/my_repo
git fetch
if git branch | grep $commit_or_branch 2> /dev/null
then
    echo "it's a branch"
fi

if git cat-file -e $commit_or_branch 2> /dev/null
then
  echo "it's a commit"
fi

Note that this only tests for local branches.. see this post if you're interested in remote branches.