I configured git so that it uses emacsclient when editing commit messages. The only problem is that these messages are edited in
fundamental-mode. Which hook should I use to have these commit messages buffer in
I believe this will do what your after, but i have not tested personally
(setq git-commit-major-mode 'markdown-mode)
Looking at the code in the link below its set with
defcustom to allow you to override to any mode you like.
Not an answer to the question (@DoMiNeLa10♦ already answered it perfectly), but I thought that it might be useful to point out that markdown is not the best highlighting mode for git commit messages.
There is a perfect mode for this and it is called
git-commit, available on Melpa.
(setq global-git-commit-mode t) to your init file will automatically open
COMMIT_EDITMSG buffers in git-commit-mode.
There are other highlighting packages for other types of git files (.gitignore, etc.) also on Melpa.
None of these packages require
git-commit-mode is actually a minor mode from which the magit
git-commit-major-mode is built).