From d2974cf48a1bc22c7adfedc91bafdd80c8494ee0 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Chmielowski?= <pchmielowski@process-one.net>
Date: Mon, 29 Jan 2018 17:25:31 +0100
Subject: [PATCH] Fix processing of ldap_memberattr_format_re option

This makes sure that "" value is handled as before options processing
overhaul.

This fixed ldap shared roster testcase
---
 src/mod_shared_roster_ldap.erl | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/mod_shared_roster_ldap.erl b/src/mod_shared_roster_ldap.erl
index 745430cad..04db34efe 100644
--- a/src/mod_shared_roster_ldap.erl
+++ b/src/mod_shared_roster_ldap.erl
@@ -575,7 +575,11 @@ mod_opt_type(ldap_memberattr_format) ->
     fun iolist_to_binary/1;
 mod_opt_type(ldap_memberattr_format_re) ->
     fun (S) ->
-	    Re = iolist_to_binary(S), {ok, MP} = re:compile(Re), MP
+	    Re = iolist_to_binary(S),
+	    case Re of
+		<<>> -> <<>>;
+		_ -> {ok, MP} = re:compile(Re), MP
+	    end
     end;
 mod_opt_type(ldap_rfilter) ->
     opt_type(ldap_rfilter);