Merge pull request #949 from basho/mra/repl-util-read-fix

Return 0 instead of doing another rt:sysread in repl_util:wait_for_reads/5

Author: Brett Hazen

src/rt.erl

@@ -664,7 +664,7 @@ wait_until(Fun) when is_function(Fun) ->
 
 %% @doc Convenience wrapper for wait_until for the myriad functions that
 %% take a node as single argument.
--spec wait_until([node()], fun((node()) -> boolean())) -> ok.
+-spec wait_until(node(), fun(() -> boolean())) -> ok | {fail, Result :: term()}.
 wait_until(Node, Fun) when is_atom(Node), is_function(Fun) ->
     wait_until(fun() -> Fun(Node) end);
 

tests/repl_util.erl

@@ -195,14 +195,17 @@ wait_until_fullsync_stopped(SourceLeader) ->
                   end).
 
 wait_for_reads(Node, Start, End, Bucket, R) ->
-    rt:wait_until(Node,
+    ok = rt:wait_until(Node,
         fun(_) ->
                 Reads = rt:systest_read(Node, Start, End, Bucket, R, <<>>, true),
                 Reads == []
         end),
-    Reads = rt:systest_read(Node, Start, End, Bucket, R, <<>>, true),
-    lager:info("Reads: ~p", [Reads]),
-    length(Reads).
+    %% rt:systest_read/6 returns a list of errors encountered while performing
+    %% the requested reads. Since we are asserting this list is empty above,
+    %% we already know that if we reached here, that the list of reads has
+    %% no errors. Therefore, we simply return 0 and do not execute another
+    %% systest_read call.
+    0.
 
 get_fs_coord_status_item(Node, SinkName, ItemName) ->
     Status = rpc:call(Node, riak_repl_console, status, [quiet]),