Add asynchronous test for pubsub using RESP3 (#1012)

* Include `unsubscribe` as a subscribe reply in RESP3

By providing the (p)unsubscribe message via the subscribe callback,
instead of via the push callback, we get the same behavior in RESP3
as in RESP2.

* Add asynchronous test for pubsub using RESP3

The testcase will subscribe to a channel, and via a second client
a message is published to the channel. After receiving the message
the testcase will unsubscribe and disconnect.

This RESP3 testcase reuses the subscribe callback from the RESP2
testcase to make sure we have a common behavior.

1 files changed, 2 insertions, 2 deletions

diff --git a/async.c b/async.c
index e37afbd..4459c19 100644
--- a/async.c
+++ b/async.c
@@ -496,8 +496,8 @@ static int redisIsSubscribeReply(redisReply *reply) {
     len = reply->element[0]->len - off;
 
     return !strncasecmp(str, "subscribe", len) ||
-           !strncasecmp(str, "message", len);
-
+           !strncasecmp(str, "message", len) ||
+           !strncasecmp(str, "unsubscribe", len);
 }
 
 void redisProcessCallbacks(redisAsyncContext *ac) {