1 files changed, 67 insertions, 0 deletions
diff --git a/lib/stdlib/src/erl_internal.erl b/lib/stdlib/src/erl_internal.erl
index 46059f42a5..5d6aa0ebe8 100644
--- a/lib/stdlib/src/erl_internal.erl
+++ b/lib/stdlib/src/erl_internal.erl
@@ -54,6 +54,8 @@
 
 -export([is_type/2]).
 
+-export([add_predefined_functions/1]).
+
 %%---------------------------------------------------------------------------
 
 %%  Erlang builtin functions allowed in guards.
@@ -569,3 +571,68 @@ is_type(term, 0) -> true;
 is_type(timeout, 0) -> true;
 is_type(tuple, 0) -> true;
 is_type(_, _) -> false.
+
+%%%
+%%% Add and export the pre-defined functions:
+%%%
+%%%   module_info/0
+%%%   module_info/1
+%%%   behaviour_info/1 (optional)
+%%%
+
+-spec add_predefined_functions(Forms) -> UpdatedForms when
+      Forms :: [erl_parse:abstract_form() | erl_parse:form_info()],
+      UpdatedForms :: [erl_parse:abstract_form() | erl_parse:form_info()].
+
+add_predefined_functions(Forms) ->
+    Forms ++ predefined_functions(Forms).
+
+predefined_functions(Forms) ->
+    Attrs = [{Name,Val} || {attribute,_,Name,Val} <- Forms],
+    {module,Mod} = lists:keyfind(module, 1, Attrs),
+    Callbacks = [Callback || {callback,Callback} <- Attrs],
+    OptionalCallbacks = get_optional_callbacks(Attrs),
+    Mpf1 = module_predef_func_beh_info(Callbacks, OptionalCallbacks),
+    Mpf2 = module_predef_funcs_mod_info(Mod),
+    Mpf = [erl_parse:new_anno(F) || F <- Mpf1++Mpf2],
+    Exp = [{F,A} || {function,_,F,A,_} <- Mpf],
+    [{attribute,0,export,Exp}|Mpf].
+
+get_optional_callbacks(Attrs) ->
+    L = [O || {optional_callbacks,O} <- Attrs, is_fa_list(O)],
+    lists:append(L).
+
+is_fa_list([{FuncName, Arity}|L])
+  when is_atom(FuncName), is_integer(Arity), Arity >= 0 ->
+    is_fa_list(L);
+is_fa_list([]) -> true;
+is_fa_list(_) -> false.
+
+module_predef_func_beh_info([], _) ->
+    [];
+module_predef_func_beh_info(Callbacks0, OptionalCallbacks) ->
+    Callbacks = [FA || {{_,_}=FA,_} <- Callbacks0],
+    List = make_list(Callbacks),
+    OptionalList = make_list(OptionalCallbacks),
+    [{function,0,behaviour_info,1,
+      [{clause,0,[{atom,0,callbacks}],[],[List]},
+       {clause,0,[{atom,0,optional_callbacks}],[],[OptionalList]}]}].
+
+make_list([]) -> {nil,0};
+make_list([{Name,Arity}|Rest]) ->
+    {cons,0,
+     {tuple,0,
+      [{atom,0,Name},
+       {integer,0,Arity}]},
+     make_list(Rest)}.
+
+module_predef_funcs_mod_info(Mod) ->
+    ModAtom = {atom,0,Mod},
+    [{function,0,module_info,0,
+      [{clause,0,[],[],
+        [{call,0,{remote,0,{atom,0,erlang},{atom,0,get_module_info}},
+          [ModAtom]}]}]},
+     {function,0,module_info,1,
+      [{clause,0,[{var,0,'X'}],[],
+        [{call,0,{remote,0,{atom,0,erlang},{atom,0,get_module_info}},
+          [ModAtom,{var,0,'X'}]}]}]}].