New client info field added to CLIENT LIST output: multi, containing the...

New client info field added to CLIENT LIST output: multi, containing the length of the current pipeline. Test modified accordingly.

src/networking.c

@@ -1085,7 +1085,7 @@ sds getClientInfoString(redisClient *client) {
     if (emask & AE_WRITABLE) *p++ = 'w';
     *p = '\0';
     return sdscatprintf(sdsempty(),
-        "addr=%s:%d fd=%d age=%ld idle=%ld flags=%s db=%d sub=%d psub=%d qbuf=%lu qbuf-free=%lu obl=%lu oll=%lu omem=%lu events=%s cmd=%s",
+        "addr=%s:%d fd=%d age=%ld idle=%ld flags=%s db=%d sub=%d psub=%d multi=%d qbuf=%lu qbuf-free=%lu obl=%lu oll=%lu omem=%lu events=%s cmd=%s",
         ip,port,client->fd,
         (long)(server.unixtime - client->ctime),
         (long)(server.unixtime - client->lastinteraction),
@@ -1093,6 +1093,7 @@ sds getClientInfoString(redisClient *client) {
         client->db->id,
         (int) dictSize(client->pubsub_channels),
         (int) listLength(client->pubsub_patterns),
+        (client->flags & REDIS_MULTI) ? client->mstate.count : -1,
         (unsigned long) sdslen(client->querybuf),
         (unsigned long) sdsavail(client->querybuf),
         (unsigned long) client->bufpos,

tests/unit/introspection.tcl

 start_server {tags {"introspection"}} {
     test {CLIENT LIST} {
         r client list
-    } {*addr=*:* fd=* age=* idle=* flags=N db=9 sub=0 psub=0 qbuf=0 qbuf-free=* obl=0 oll=0 omem=0 events=r cmd=client*}
+    } {*addr=*:* fd=* age=* idle=* flags=N db=9 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=* obl=0 oll=0 omem=0 events=r cmd=client*}
 }