Merge pull request #147 from inaka/elbrujohalcon.147.error_using_sumo…

…_find_to_retri

Error using sumo:find to retrieve an inexistent element

src/sumo_store_mnesia.erl

@@ -143,16 +143,20 @@ find_by(DocName, Conditions, Limit, Offset, State) ->
   sumo_store:result([sumo_internal:doc()], state()).
 find_by(DocName, Conditions, [], Limit, Offset, State) ->
   MatchSpec = build_match_spec(DocName, Conditions),
+  Transaction0 = fun() -> mnesia:select(DocName, MatchSpec) end,
+  TransactionL =
+    fun() ->
+      case mnesia:select(DocName, MatchSpec, Offset + Limit, read) of
+        {ManyItems, _Cont} ->
+          lists:sublist(ManyItems, Offset + 1, Limit);
+        '$end_of_table' ->
+          []
+      end
+    end,
   Transaction =
     case Limit of
-      0 ->
-        fun() -> mnesia:select(DocName, MatchSpec) end;
-      Limit ->
-        fun() ->
-          {ManyItems, _Cont} =
-            mnesia:select(DocName, MatchSpec, Offset + Limit, read),
-          lists:sublist(ManyItems, Offset + 1, Limit)
-        end
+      0 -> Transaction0;
+      Limit -> TransactionL
     end,
   case mnesia:transaction(Transaction) of
     {aborted, Reason} ->

test/sumo_basic_SUITE.erl

@@ -8,6 +8,7 @@
         ]).
 
 -export([
+         find/1,
          find_all/1,
          find_by/1,
          delete_all/1,
@@ -54,6 +55,9 @@ end_per_suite(Config) ->
 %%% Exported Tests Functions
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+find(_Config) ->
+  run_all_stores(fun find_module/1).
+
 find_all(_Config) ->
   run_all_stores(fun find_all_module/1).
 
@@ -84,6 +88,12 @@ init_store(Module) ->
   %% Sync Timeout.
   sync_timeout(Module).
 
+find_module(Module) ->
+  [First, Second | _] = sumo:find_all(Module),
+  First = sumo:find(Module, Module:id(First)),
+  Second = sumo:find(Module, Module:id(Second)),
+  notfound = sumo:find(Module, 0).
+
 find_all_module(Module) ->
   6 = length(sumo:find_all(Module)).