epdg: Introduce test TC_authinfo_twice

Related: OS#6391
Change-Id: I86ef2bf9a0676735343d5a5c0f4ff12f552216d2
diff --git a/epdg/EPDG_Tests.ttcn b/epdg/EPDG_Tests.ttcn
index 45d7a1d..164f14b 100644
--- a/epdg/EPDG_Tests.ttcn
+++ b/epdg/EPDG_Tests.ttcn
@@ -928,6 +928,20 @@
 	setverdict(pass);
 }
 
+/* Emulate UE doing MAR+MAA, then repeating and continuing. */
+private function f_TC_authinfo_twice(charstring id) runs on EPDG_ConnHdlr {
+	f_GSUP_AI_success();
+	f_initial_attach();
+}
+testcase TC_authinfo_twice() runs on MTC_CT {
+	var EPDG_ConnHdlrPars pars := f_init_pars();
+	var EPDG_ConnHdlr vc_conn;
+	f_init();
+	vc_conn := f_start_handler(refers(f_TC_authinfo_twice), pars);
+	vc_conn.done;
+	setverdict(pass);
+}
+
 private function f_TC_ho_lte_to_wifi(charstring id) runs on EPDG_ConnHdlr {
 	f_initial_attach();
 	/* Whenever UE comes from 3GPP, PGW may activate a dedicated S2b bearer
@@ -1064,6 +1078,7 @@
 control {
 	execute ( TC_authinfo_normal() );
 	execute ( TC_authinfo_MAA_unknown_user() );
+	execute ( TC_authinfo_twice() );
 	execute ( TC_ho_lte_to_wifi() );
 	execute ( TC_ho_wifi_to_lte() );
 	execute ( TC_s2b_CreateSession_rejected() );