Merge branch 'jdb-fix-mixed-cluster'

As part of merge, modified verify_basic_upgrade test to use new
deploy_nodes API

tests/verify_basic_upgrade.erl

@@ -0,0 +1,36 @@
+-module(verify_basic_upgrade).
+-export([verify_basic_upgrade/0]).
+-include_lib("eunit/include/eunit.hrl").
+
+verify_basic_upgrade() ->
+    OldVsns = ["1.0.3", "1.1.2"],
+    [build_cluster(OldVsn, current) || OldVsn <- OldVsns],
+    [build_cluster(current, OldVsn) || OldVsn <- OldVsns],
+    lager:info("Test ~p passed", [?MODULE]),
+    ok.
+
+build_cluster(Vsn1, Vsn2) ->
+    lager:info("Testing versions: ~p <- ~p", [Vsn1, Vsn2]),
+    Nodes = rt:deploy_nodes([Vsn1, Vsn2]),
+    [Node1, Node2] = Nodes,
+    lager:info("Writing 100 keys to ~p", [Node1]),
+    timer:sleep(1000),
+    rt:systest_write(Node1, 100, 3),
+    ?assertEqual([], rt:systest_read(Node1, 100, 1)),
+
+    lager:info("Join ~p to ~p", [Node2, Node1]),
+    rt:join(Node2, Node1),
+
+    ?assertEqual(ok, rt:wait_until_nodes_ready(Nodes)),
+    ?assertEqual(ok, rt:wait_until_ring_converged(Nodes)),
+    ?assertEqual(ok, rt:wait_until_no_pending_changes(Nodes)),
+    ?assertEqual([], rt:systest_read(Node1, 100, 1)),
+
+    (Vsn1 /= current) andalso rtdev:upgrade(Node1, current),
+    (Vsn2 /= current) andalso rtdev:upgrade(Node2, current),
+
+    timer:sleep(1000),
+    lager:info("Ensuring keys still exist"),
+    rt:systest_read(Node1, 100, 1),
+    ?assertEqual([], rt:systest_read(Node1, 100, 1)),
+    ok.