Retrieving branch names from within a post-checkout hook

问题

When switching from one branch to another in Git, is there any way to retrieve the names of both branches from within the post-checkout hook?

So assuming I were to run the following two commands:

$ git branch
* branch_a
  branch_b
  master

$ git checkout branch_b
Switched to branch 'branch_b'

I'd be looking for the following two strings (in the post-checkout hook):

"branch_a"
"branch_b"

回答1:

You can use git reflog inside your hook to get the previous and next branch. Here a simple working example:

#!/bin/bash

# $6 = previous branch, $8 is next branch
git reflog | awk 'NR==1{ print $6 " -> " $8; exit }'

EDIT: updated answer. Here the previous:

This hook is given with three arguments:

• the ref of the previous HEAD
• the ref of the new HEAD
• 1 if it was a branch checkout, 0 for a file checkout.

With the two firsts you should have enough information for what you are trying to do.

来源：https://stackoverflow.com/questions/25590267/retrieving-branch-names-from-within-a-post-checkout-hook