fish-shell/share/functions/__fish_complete_cd.fish

function __fish_complete_cd -d "Completions for the cd command"
	#
	# We can't simply use __fish_complete_directories because of the CDPATH
	#
	set -l wd $PWD

	# Check if CDPATH is set

	set -l mycdpath

	if test -z $CDPATH[1]
		set mycdpath .
	else
		set mycdpath $CDPATH
	end

    set -l ctoken (commandline -ct)
	if echo $ctoken | sgrep '^/\|^\./\|^\.\./\|^~/' >/dev/null
		# This is an absolute search path
		eval printf '\%s\\tDirectory\\n' $ctoken\*/
	else
		# This is a relative search path
		# Iterate over every directory in CDPATH
		# and check for possible completions

		for i in $mycdpath
			# Move to the initial directory first,
			# in case the CDPATH directory is relative

			builtin cd $wd
			eval builtin cd $i

			eval printf '"%s\tDirectory in "'$i'"\n"' $ctoken\*/
		end
	end

	builtin cd $wd
end