swim: set 'left' status in self on swim_quit()

swim_quit() notifies all the members that this instance has left
the cluster. Strangely, except self. It is not a real bug, but
showing 'left' status in self struct swim_member would be more
correct than 'alive', obviously.

It is possible, that self struct swim_member was referenced by a
user - this is how 'self' can be available after SWIM instance
deletion.

Part of #3234

src/lib/swim/swim.c

@@ -2002,6 +2002,7 @@ swim_quit(struct swim *swim)
 	assert(rc == 2);
 	mp_encode_map(header, rc);
 	swim_quit_step_complete(task, &swim->scheduler, 0);
+	swim->self->status = MEMBER_LEFT;
 }
 
 struct swim_member *

test/unit/swim.c

@@ -502,14 +502,20 @@ swim_test_undead(void)
 static void
 swim_test_quit(void)
 {
-	swim_start_test(9);
+	swim_start_test(10);
 	int size = 3;
 	struct swim_cluster *cluster = swim_cluster_new(size);
 	for (int i = 0; i < size; ++i) {
 		for (int j = 0; j < size; ++j)
 			swim_cluster_add_link(cluster, i, j);
 	}
+	struct swim *s0 = swim_cluster_member(cluster, 0);
+	struct swim_member *s0_self = swim_self(s0);
+	swim_member_ref(s0_self);
 	swim_cluster_quit_node(cluster, 0);
+	is(swim_member_status(s0_self), MEMBER_LEFT,
+	   "'self' is 'left' immediately after quit");
+	swim_member_unref(s0_self);
 	is(swim_cluster_wait_status_everywhere(cluster, 0, MEMBER_LEFT, 0),
 	   0, "'quit' is sent to all the members without delays between "\
 	   "dispatches")
@@ -528,7 +534,7 @@ swim_test_quit(void)
 	 * received the 'quit' message with the same UUID. Of
 	 * course, it should be refuted.
 	 */
-	struct swim *s0 = swim_cluster_member(cluster, 0);
+	s0 = swim_cluster_member(cluster, 0);
 	struct tt_uuid s0_uuid = *swim_member_uuid(swim_self(s0));
 	struct swim *s1 = swim_cluster_member(cluster, 1);
 	swim_remove_member(s1, &s0_uuid);

test/unit/swim.result

@@ -122,16 +122,17 @@ ok 11 - subtests
 ok 12 - subtests
 	*** swim_test_packet_loss: done ***
 	*** swim_test_quit ***
-    1..9
-    ok 1 - 'quit' is sent to all the members without delays between dispatches
-    ok 2 - quited member S1 has returned and refuted the old status
-    ok 3 - another member S2 has taken the quited UUID
-    ok 4 - S3 did not add S1 back when received its 'quit'
-    ok 5 - S2 finally got 'quit' message from S1, but with its 'own' UUID - refute it
-    ok 6 - S3 sees S1 as left
-    ok 7 - S2 does not see S1 at all
-    ok 8 - after more time S1 is dropped from S3
-    ok 9 - and still is not added to S2 - left members can not be added
+    1..10
+    ok 1 - 'self' is 'left' immediately after quit
+    ok 2 - 'quit' is sent to all the members without delays between dispatches
+    ok 3 - quited member S1 has returned and refuted the old status
+    ok 4 - another member S2 has taken the quited UUID
+    ok 5 - S3 did not add S1 back when received its 'quit'
+    ok 6 - S2 finally got 'quit' message from S1, but with its 'own' UUID - refute it
+    ok 7 - S3 sees S1 as left
+    ok 8 - S2 does not see S1 at all
+    ok 9 - after more time S1 is dropped from S3
+    ok 10 - and still is not added to S2 - left members can not be added
 ok 13 - subtests
 	*** swim_test_quit: done ***
 	*** swim_test_uri_update ***