git - how to get default branch?

Question

My team alternates between usage of dev and master as default branch for several repos and I would like to write a script that checks for the default branch when entering a

Answer 1

There doesn't seem to be an answer that doesn't require cloning so far

This requires git 2.8.0 or newer

$ git ls-remote --symref git@github.com:pre-commit/pre-commit.github.io HEAD
ref: refs/heads/real_master HEAD
e100a6a3c72b4e54f0d176f791dfd2dbd7eb5fa7    HEAD