tests: Add scansion test for #689 about keeping the full subscription request stanza

author: Kim Alvefur <zash@zash.se>
date: Fri, 30 Nov 2018 23:58:55 +0100
child: 9668:6fbf8fa7ab8e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spec/scansion/keep_full_sub_req.scs	Fri Nov 30 23:58:55 2018 +0100
@@ -0,0 +1,37 @@
+# server MUST keep a record of the complete presence stanza comprising the subscription request (#689)
+
+[Client] Alice
+	jid: pars-a@localhost
+	password: password
+
+[Client] Bob
+	jid: pars-b@localhost
+	password: password
+
+---------
+
+Alice connects
+
+Alice sends:
+	<presence to="${Bob's JID}" type="subscribe">
+		<preauth xmlns="urn:xmpp:pars:0" token="1tMFqYDdKhfe2pwp" />
+	</presence>
+
+Alice disconnects
+
+Bob connects
+
+Bob sends:
+	<presence/>
+
+Bob receives:
+	<presence from="${Bob's full JID}"/>
+	
+
+Bob receives:
+	<presence from="${Alice's JID}">
+		<preauth xmlns="urn:xmpp:pars:0" token="1tMFqYDdKhfe2pwp" />
+	</presence>
+
+Bob disconnects
+