mnesia: Do not unconditionally delete index keys

delete_object(NonExistingRecord) deleted index keys even if the record
didn't exist, in set tables, and nothing was deleted from the real table.

Solve this by doing the same checks as was done for bag tables.

Fixes GH-5040

2 files changed, 40 insertions, 17 deletions

diff --git a/lib/mnesia/src/mnesia_index.erl b/lib/mnesia/src/mnesia_index.erl
index 2ca6c55870..964c50aa52 100644
--- a/lib/mnesia/src/mnesia_index.erl
+++ b/lib/mnesia/src/mnesia_index.erl
@@ -139,22 +139,15 @@ del_object_index(#index{pos_list = PosL, setorbag = SorB}, Storage, Tab, K, Obj)
     del_object_index2(PosL, SorB, Storage, Tab, K, Obj).
 
 del_object_index2([], _, _Storage, _Tab, _K, _Obj) -> ok;
-del_object_index2([{{Pos, Type}, Ixt} | Tail], SoB, Storage, Tab, K, Obj) ->
+del_object_index2([{{Pos, Type}, Ixt} | Tail], SoB, Storage, Tab, Key, Obj) ->
     ValsF = index_vals_f(Storage, Tab, Pos),
-    case SoB of
-	bag ->
-	    del_object_bag(Type, ValsF, Tab, K, Obj, Ixt);
-	_ -> %% If set remove the tuple in index table
-	    del_ixes(Type, Ixt, ValsF, Obj, K)
-    end,
-    del_object_index2(Tail, SoB, Storage, Tab, K, Obj).
-
-del_object_bag(Type, ValsF, Tab, Key, Obj, Ixt) ->
-    IxKeys = ValsF(Obj),
     Found = [{X, ValsF(X)} || X <- mnesia_lib:db_get(Tab, Key)],
-    del_object_bag_(IxKeys, Found, Type, Tab, Key, Obj, Ixt).
+    IxKeys = ValsF(Obj),
+    del_object_index3(IxKeys, Found, Type, Tab, Key, Obj, Ixt),
+    del_object_index2(Tail, SoB, Storage, Tab, Key, Obj).
+
 
-del_object_bag_([IxK|IxKs], Found, Type, Tab, Key, Obj, Ixt) ->
+del_object_index3([IxK|IxKs], Found, Type, Tab, Key, Obj, Ixt) ->
     case [X || {X, Ixes} <- Found, lists:member(IxK, Ixes)] of
         [Old] when Old =:= Obj ->
 	    case Type of
@@ -166,8 +159,8 @@ del_object_bag_([IxK|IxKs], Found, Type, Tab, Key, Obj, Ixt) ->
         _ ->
 	    ok
     end,
-    del_object_bag_(IxKs, Found, Type, Tab, Key, Obj, Ixt);
-del_object_bag_([], _, _, _, _, _, _) ->
+    del_object_index3(IxKs, Found, Type, Tab, Key, Obj, Ixt);
+del_object_index3([], _, _, _, _, _, _) ->
     ok.
 
 clear_index(Index, Tab, K, Obj) ->
diff --git a/lib/mnesia/test/mnesia_trans_access_test.erl b/lib/mnesia/test/mnesia_trans_access_test.erl
index 723a85fd2c..dec396252b 100644
--- a/lib/mnesia/test/mnesia_trans_access_test.erl
+++ b/lib/mnesia/test/mnesia_trans_access_test.erl
@@ -31,7 +31,7 @@
          basic_nested/1, mix_of_nested_activities/1,
          nested_trans_both_ok/1, nested_trans_child_dies/1,
          nested_trans_parent_dies/1, nested_trans_both_dies/1,
-         index_match_object/1, index_read/1,index_write/1,
+         index_match_object/1, index_read/1,index_write/1, index_delete_object/1,
          index_update_set/1, index_update_bag/1,
          add_table_index_ram/1, add_table_index_disc/1,
          add_table_index_disc_only/1, create_live_table_index_ram/1,
@@ -77,7 +77,7 @@ groups() ->
        nested_trans_parent_dies, nested_trans_both_dies]},
      {index_tabs, [],
       [index_match_object, index_read, {group, index_update},
-       index_write]},
+       index_write, index_delete_object]},
      {index_update, [],
       [index_update_set, index_update_bag]},
      {index_lifecycle, [],
@@ -1078,6 +1078,36 @@ index_write(Config)when is_list(Config) ->
     ?verify_mnesia(Nodes, []).
 
 
+index_delete_object(suite) -> [];
+index_delete_object(doc) -> ["See issue: GH-5040"];
+index_delete_object(Config) when is_list(Config) ->
+    Nodes = ?acquire_nodes(1, Config),
+    {atomic, ok} = mnesia:create_table(ram_set,[{index, [ix]}, {attributes, [key, ix, val]},
+                                                {ram_copies, Nodes}]),
+    {atomic, ok} = mnesia:create_table(do_set, [{index, [ix]}, {attributes, [key, ix, val]},
+                                                {disc_only_copies, Nodes}]),
+    {atomic, ok} = mnesia:create_table(ram_bag,[{index, [ix]}, {attributes, [key, ix, val]},
+                                                {ram_copies, Nodes}]),
+    {atomic, ok} = mnesia:create_table(do_bag, [{index, [ix]}, {attributes, [key, ix, val]},
+                                                {disc_only_copies, Nodes}]),
+    Test = fun(Tab) ->
+                   io:format("Testing: ~p~n",[Tab]),
+                   Rec = {Tab, 2, 4, data},
+                   Rec2 = {Tab, 3, 5, data},
+                   ok = mnesia:dirty_write(Rec),
+                   ok = mnesia:dirty_write(Rec2),
+                   [Rec] = mnesia:dirty_index_read(Tab, 4, ix),
+                   ?match(ok, mnesia:dirty_delete_object({Tab, 2, 4, does_not_exist})),
+                   [Rec] = mnesia:dirty_read(Tab, 2),
+                   [Rec] = mnesia:dirty_index_read(Tab, 4, ix),
+                   ?match(ok, mnesia:dirty_delete_object(Rec)),
+                   [] = mnesia:dirty_read(Tab, 2),
+                   [] = mnesia:dirty_index_read(Tab, 4, ix),
+                   [Rec2] = mnesia:dirty_read(Tab, 3),
+                   [Rec2] = mnesia:dirty_index_read(Tab, 5, ix)
+           end,
+    [Test(Tab) || Tab <- [ram_set,do_set,ram_bag,do_bag]],
+    ?verify_mnesia(Nodes, []).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% Add and drop indecies