Split all the e2e tests in their own files

Some duplication is avoided, but most importantly: it’s much much cleaner,
easier to find, functions have been cleaned up (functools.partial usages are
now hidden), etc.

tests/end_to_end/scenarios/channel_history.py

@@ -0,0 +1,18 @@
+from scenarios import *
+
+scenario = (
+    scenarios.simple_channel_join.scenario,
+
+    # Send one channel message
+    send_stanza("<message from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}' type='groupchat'><body>coucou</body></message>"),
+    expect_stanza("/message[@from='#foo%{irc_server_one}/{nick_one}'][@to='{jid_one}/{resource_one}'][@type='groupchat']/body[text()='coucou']"),
+
+    # Second user joins
+    send_stanza("<presence from='{jid_one}/{resource_two}' to='#foo%{irc_server_one}/{nick_one}' />"),
+    expect_stanza("/presence[@to='{jid_one}/{resource_two}'][@from='#foo%{irc_server_one}/{nick_one}']/muc_user:x/muc_user:item[@affiliation='admin'][@jid='{lower_nick_one}%{irc_server_one}/~{nick_one}@localhost'][@role='moderator']",
+                  "/presence/muc_user:x/muc_user:status[@code='110']"),
+    # Receive the history message
+    expect_stanza("/message[@from='#foo%{irc_server_one}/{nick_one}']/body[text()='coucou']",
+                  "/message/delay:delay[@from='#foo%{irc_server_one}']"),
+    expect_stanza("/message[@from='#foo%{irc_server_one}'][@type='groupchat']/subject[not(text())]"),
+)