BUG: sendemail-validate hook is run too early

I'm trying to use the sendemail-validate hook to validate the recipients of the patch email, among other things. Turns out the hook gets run immediately on the input patches, *not* on the "e-mail to be sent" as claimed by githooks(5).

This means the recipients added by git send-email automatically or on the git send-email command-line, or any changes done by the user with --annotate will not be validated.

This is easy to demonstrate in a git repo with e.g.

$ ln -s /bin/cat .git/hooks/sendemail-validate $ git send-email --dry-run -1 --to bypass-validation@example.com

The file passed to the validate hook does not have the address.

If changing the location of the current validation hook seems too risky, as apparently it's been like this for more than a decade, I suggest adding another hook on the actual email to be sent.

BR, Jani.