hphp/hack/src/typing/tast_check/abstract_class_check.ml

   1 (**
   2  * Copyright (c) 2018, Facebook, Inc.
   3  * All rights reserved.
   4  *
   5  * This source code is licensed under the MIT license found in the
   6  * LICENSE file in the "hack" directory of this source tree.
   7  *
   8  *)
   9
  10 open Tast
  11 open Core_kernel
  12
  13 module Env = Tast_env
  14 module Cls = Typing_classes_heap
  15 module SN = Naming_special_names
  16
  17 let check_expr env (pos, e) =
  18   match e with
  19   | Class_const ((_, CIparent), ((_, construct)))
  20     when construct = SN.Members.__construct ->
  21     let tenv = Env.tast_env_as_typing_env env in
  22     begin match Env.get_class env (Typing_env.get_parent_id tenv) with
  23     | Some parent_class when Cls.kind parent_class = Ast.Cabstract ->
  24       if fst (Cls.construct parent_class) = None then
  25         Errors.parent_abstract_call construct (fst pos) (Cls.pos parent_class);
  26     | _ -> ()
  27     end
  28   | _ -> ()
  29
  30 let check_method_body env m =
  31   let named_body = m.m_body in
  32   if m.m_abstract && named_body.fb_ast <> []
  33   then Errors.abstract_with_body m.m_name;
  34   let tenv = Env.tast_env_as_typing_env env in
  35   if not (Typing_env.is_decl tenv) && not m.m_abstract && named_body.fb_ast = []
  36   then Errors.not_abstract_without_body m.m_name
  37
  38 let check_class _ c =
  39   if c.c_kind = Ast.Cabstract && c.c_final then begin
  40     let err m =
  41       Errors.nonstatic_method_in_abstract_final_class (fst m.m_name) in
  42     List.iter c.c_methods err;
  43     Option.iter c.c_constructor err
  44   end
  45
  46 let handler = object
  47   inherit Tast_visitor.handler_base
  48
  49   method! at_expr env e = check_expr env e
  50
  51   method! at_method_ env m = check_method_body env m
  52
  53   method! at_class_ env c = check_class env c
  54 end