do not add abstract fields without expressions to field list and error accordingly (closes #2344)

typeload.ml

@@ -1639,7 +1639,7 @@ let init_class ctx c p context_init herits fields =
 			} in
 			ctx.curfield <- cf;
 			bind_var ctx cf e stat inline;
-			f, false, cf
+			f, false, cf, true
 		| FFun fd ->
 			let params = type_function_params ctx fd f.cff_name p in
 			if inline && c.cl_interface then error "You can't declare inline methods in interfaces" p;
@@ -1726,6 +1726,7 @@ let init_class ctx c p context_init herits fields =
 				cf_overloads = [];
 			} in
 			let do_bind = ref (((not c.cl_extern || inline) && not c.cl_interface) || cf.cf_name = "__init__") in
+			let do_add = ref true in
 			(match c.cl_kind with
 				| KAbstractImpl a ->
 					let m = mk_mono() in
@@ -1738,7 +1739,8 @@ let init_class ctx c p context_init herits fields =
 								| None -> error ("Functions without expressions must have an explicit return type") f.cff_pos
 								| Some _ -> ()
 							end;
-							do_bind := false
+							do_add := false;
+							do_bind := false;
 						end
 					in
 					let rec loop ml = match ml with
@@ -1829,7 +1831,7 @@ let init_class ctx c p context_init herits fields =
 				t
 			) "type_fun" in
 			if !do_bind then bind_type ctx cf r (match fd.f_expr with Some e -> snd e | None -> f.cff_pos) is_macro;
-			f, constr, cf
+			f, constr, cf, !do_add
 		| FProp (get,set,t,eo) ->
 			(match c.cl_kind with
 			| KAbstractImpl a when Meta.has Meta.Impl f.cff_meta ->
@@ -1906,7 +1908,7 @@ let init_class ctx c p context_init herits fields =
 			} in
 			ctx.curfield <- cf;
 			bind_var ctx cf eo stat inline;
-			f, false, cf
+			f, false, cf, true
 	in
 	let rec check_require = function
 		| [] -> None
@@ -1931,7 +1933,7 @@ let init_class ctx c p context_init herits fields =
 	List.iter (fun f ->
 		let p = f.cff_pos in
 		try
-			let fd , constr, f = loop_cf f in
+			let fd , constr, f, do_add = loop_cf f in
 			let is_static = List.mem AStatic fd.cff_access in
 			if (is_static || constr) && c.cl_interface && f.cf_name <> "__init__" then error "You can't declare static fields in interfaces" p;
 			begin try
@@ -1973,7 +1975,9 @@ let init_class ctx c p context_init herits fields =
 					else
 						display_error ctx ("Duplicate class field declaration : " ^ f.cf_name) p
 				else
-				if is_static then begin
+				if not do_add then
+					()
+				else if is_static then begin
 					c.cl_statics <- PMap.add f.cf_name f c.cl_statics;
 					c.cl_ordered_statics <- f :: c.cl_ordered_statics;
 				end else begin

typer.ml

@@ -1140,7 +1140,19 @@ and type_field ctx e i p mode =
 			| TInst({cl_kind = KAbstractImpl a},_) -> TAbstract(a,[])
 			| _ -> e.etype
 		in
-		if not ctx.untyped then display_error ctx (string_error i (string_source t) (s_type (print_context()) t ^ " has no field " ^ i)) p;
+		let has_special_field a =
+			List.exists (fun (_,cf) -> cf.cf_name = i) a.a_ops
+			|| List.exists (fun (_,_,cf) -> cf.cf_name = i) a.a_unops
+			|| List.exists (fun cf -> cf.cf_name = i) a.a_array
+		in
+		if not ctx.untyped then begin
+			match t with
+			| TAbstract(a,_) when has_special_field a ->
+				(* the abstract field is not part of the field list, which is only true when it has no expression (issue #2344) *)
+				display_error ctx ("Field " ^ i ^ " cannot be called directly because it has no expression") p;
+			| _ ->
+				display_error ctx (string_error i (string_source t) (s_type (print_context()) t ^ " has no field " ^ i)) p;
+		end;
 		AKExpr (mk (TField (e,FDynamic i)) (mk_mono()) p)
 	in
 	match follow e.etype with