xdg-wrappers: add mbsync, make wrappers use next-in-path

The new next-in-path utility function finds the next entry for the
wrapped name in PATH after the called script, instead of hardcoding the
usual location for a system install.

lib/next-in-path.zsh

@@ -0,0 +1,12 @@
+# find next entry in PATH for wrapper scripts
+# Usage: next-in-path <program name> <current $0>
+next-in-path() {
+	entries=( $(which -a $1) )
+	index=${entries[(ie)$2]} 
+	if [[ $index -le ${#entries} ]]; then
+		# found $0, use next entry
+		echo $entries[$((index + 1))]
+	else
+		echo $entries[1]
+	fi
+}

xdg-wrappers/mbsync

@@ -0,0 +1,3 @@
+#!/bin/zsh
+source ${$(realpath "$0"):h:h}/lib/next-in-path.zsh
+$(next-in-path mbsync $0) -c ${XDG_CONFIG_HOME:-$HOME/.config}/mbsyncrc $@

xdg-wrappers/rg

@@ -0,0 +1,4 @@
+#!/bin/zsh
+source ${$(realpath "$0"):h:h}/lib/next-in-path.zsh
+export RIPGREP_CONFIG_PATH=${XDG_CONFIG_HOME:-$HOME/.config}/ripgreprc
+$(next-in-path rg $0) $@