Which shell used for git '!' aliases?

Question

What default shell is used by git when executing an alias starting with !?

I\'m suspecting it\'s /bin/sh, because I\'m getting different be

Answer 1

As described here, you can see more with:

GIT_TRACE=1 git test

The workaround is to create a shell script (whose first line can be a shebang #!/bin/bash) named git-xxx. Then any git xxx call would invoke that script (provided it is in the $PATH).

As the OP Tom Hale adds in the comments, /bin/sh is used:

trace: exec: '/bin/sh' '-c' 'echo Which shell?' 
'echo Which shell?'