Push an open a GitLab MR with a custom title and description (install in $PATH as git-pmr)

git-pmr.sh

#!/bin/sh
# A crapp tool to push and open a gitlab MR
# with just one command!

# --force-with-lease ensures that we don't override any commits which only exist
# on the remote. But it will let you overwrite commits you've ammended.
cmd="git push --force-with-lease -o merge_request.create -o merge_request.description="

case $# in
	1)
		# Only set description
		cmd="${cmd}\"$1\""
	;;
	2)
		cmd="${cmd}\"$2\" -o merge_request.title=\"$1\""
	;;
	*)
		echo "Usage: $0 [title] <description>"
		exit 1
	;;
esac

# Check if the remote is up to date (if git push would actually do anything)
# if it isn't (because you forgot about git-pmr when pushing) then we can prompt
# to push anyway
# https://unix.stackexchange.com/questions/678795/is-there-a-better-way-than-string-output-hacks-to-check-git-checkout-needs-a-pul
same_commit(){
    set -- $(git rev-parse "$@")
    [ "$1" = "$2" ]
}

local_branch="$(git rev-parse --abbrev-ref HEAD 2>/dev/null)"
remote_ref="$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2>/dev/null)"
upstream="$(echo $remote_ref | cut -d"/" -f1)"
remote_branch="${remote_ref#$upstream/}"
if [ -n "$remote_branch" ]; then
	# FIXME: this is gonna suck when you have a lot of remotes...
	git remote update
	# If the remote branch is identical to this one then git push won't
	# do anything and GitLab's special options handling won't trigger...
	# work around this by deleting the remote branch iff it's identical
	# to our local one.
	if same_commit HEAD "$remote_ref"; then
		read -r -p "Remote branch '$remote_ref' is up to date. Delete it? [y/N] " response
		if [[ "$response" =~ ^([yY][eE][sS]|[yY])$ ]]; then
			git push -d "$upstream" "$remote_branch"
		else
			exit 0
		fi
	fi
fi

eval "$cmd"