anchor.diff:  tree_fold_should_return_targets_limited_by_size(Config) ->
       [Worker | _] = ?config(cluster_worker_nodes, Config),
       LinksNum = 1000,
  -    AllLinks = add_links(Worker, ?CTX, ?KEY, ?LINK_TREE_ID, LinksNum),
  +    AllLinks = add_links(Worker, ?CTX(?KEY), ?KEY, ?LINK_TREE_ID, LinksNum),
       lists:foreach(fun(Size) ->
  -        Links = fold_links(Worker, ?CTX, ?KEY, #{size => Size}),
  +        Links = fold_links(Worker, ?CTX(?KEY), ?KEY, #{size => Size}),
           ?assertEqual(get_expected_links(AllLinks, 0, Size), Links)
       end, lists:seq(0, LinksNum)).
   
   tree_fold_should_return_targets_from_offset_and_limited_by_size(Config) ->
       [Worker | _] = ?config(cluster_worker_nodes, Config),
       LinksNum = 100,
  -    AllLinks = add_links(Worker, ?CTX, ?KEY, ?LINK_TREE_ID, LinksNum),
  +    AllLinks = add_links(Worker, ?CTX(?KEY), ?KEY, ?LINK_TREE_ID, LinksNum),
       lists:foreach(fun(Offset) ->
           lists:foreach(fun(Size) ->
  -            Links = fold_links(Worker, ?CTX, ?KEY, #{
  +            Links = fold_links(Worker, ?CTX(?KEY), ?KEY, #{
                   offset => Offset,
                   size => Size
               }),
  
positive.code:     ]).
  
  -define(MODEL, ets_cached_model).
  -define(MEM_CTX, ?MEM_CTX(?MODEL)).
  -define(CTX, #{
      model => ?MODEL,
      mutator_pid => self(),
  
negative.code: tree_fold_should_return_all_targets(Config) ->
      [Worker | _] = ?config(cluster_worker_nodes, Config),
      LinksNum = 1000,
      AllLinks = add_links(Worker, ?CTX(?KEY), ?KEY, ?LINK_TREE_ID, LinksNum),
      Links = fold_links(Worker, ?CTX(?KEY), ?KEY, #{}),
      ?assertEqual(get_expected_links(AllLinks), Links).
  
  tree_fold_should_return_targets_from_offset(Config) ->
      [Worker | _] = ?config(cluster_worker_nodes, Config),
      LinksNum = 1000,
      AllLinks = add_links(Worker, ?CTX(?KEY), ?KEY, ?LINK_TREE_ID, LinksNum),
      lists:foreach(fun(Offset) ->
          Links = fold_links(Worker, ?CTX(?KEY), ?KEY, #{offset => Offset}),
          ?assertEqual(get_expected_links(AllLinks, Offset), Links)
      end, lists:seq(0, LinksNum)).
  
  tree_fold_should_return_targets_from_link(Config) ->
      [Worker | _] = ?config(cluster_worker_nodes, Config),
      LinksNum = 1000,
      AllLinks = add_links(Worker, ?CTX(?KEY), ?KEY, ?LINK_TREE_ID, LinksNum),
      Names = lists:map(fun(#link{name = Name}) -> Name end, AllLinks),
      lists:foreach(fun({Offset, Name}) ->
          Links = fold_links(Worker, ?CTX(?KEY), ?KEY, #{
              prev_tree_id => ?LINK_TREE_ID,
              prev_link_name => Name
          }),
  