[clang] Find fields from the properties corresponding to the property implementations.

Summary: When a property was defined in a protocol, we were not translating its attributes which leads to retain cycles false positives. This diff fixes it. It also refactors the code for translating fields a bit.

Reviewed By: mbouaziz

Differential Revision: D7136355

fbshipit-source-id: b5e7445

infer/src/clang/cField_decl.ml

@@ -66,31 +66,38 @@ let build_sil_field qual_type_to_sil_type tenv class_tname field_name qual_type
 
 
 (* Given a list of declarations in an interface returns a list of fields  *)
-let rec get_fields qual_type_to_sil_type tenv class_tname decl_list =
+let get_fields qual_type_to_sil_type tenv class_tname decl_list =
   let open Clang_ast_t in
-  let add_field name_info (qt: qual_type) attributes decl_list' =
-    let fields = get_fields qual_type_to_sil_type tenv class_tname decl_list' in
-    let field_tuple =
-      build_sil_field qual_type_to_sil_type tenv class_tname name_info qt attributes
-    in
-    CGeneral_utils.append_no_duplicates_fields [field_tuple] fields
+  let get_sil_field name_info (qt: qual_type) property_attributes =
+    build_sil_field qual_type_to_sil_type tenv class_tname name_info qt property_attributes
   in
-  match decl_list with
-  | [] ->
-      []
-  | (ObjCPropertyDecl (_, _, obj_c_property_decl_info)) :: decl_list'
-    -> (
-      let ivar_decl_ref = obj_c_property_decl_info.Clang_ast_t.opdi_ivar_decl in
-      match CAst_utils.get_decl_opt_with_decl_ref ivar_decl_ref with
-      | Some ObjCIvarDecl (_, name_info, qual_type, _, _) ->
-          let attributes = obj_c_property_decl_info.Clang_ast_t.opdi_property_attributes in
-          add_field name_info qual_type attributes decl_list'
-      | _ ->
-          get_fields qual_type_to_sil_type tenv class_tname decl_list' )
-  | (ObjCIvarDecl (_, name_info, qual_type, _, _)) :: decl_list' ->
-      add_field name_info qual_type [] decl_list'
-  | _ :: decl_list' ->
-      get_fields qual_type_to_sil_type tenv class_tname decl_list'
+  let rec get_field fields decl =
+    match decl with
+    | ObjCPropertyDecl (_, _, obj_c_property_decl_info)
+      -> (
+        let ivar_decl_ref = obj_c_property_decl_info.Clang_ast_t.opdi_ivar_decl in
+        let property_attributes = obj_c_property_decl_info.Clang_ast_t.opdi_property_attributes in
+        match CAst_utils.get_decl_opt_with_decl_ref ivar_decl_ref with
+        | Some ObjCIvarDecl (_, name_info, qual_type, _, _) ->
+            let field = get_sil_field name_info qual_type property_attributes in
+            CGeneral_utils.add_no_duplicates_fields field fields
+        | _ ->
+            fields )
+    | ObjCPropertyImplDecl (_, obj_c_property_impl_decl_info)
+      -> (
+        let property_decl_opt = obj_c_property_impl_decl_info.Clang_ast_t.opidi_property_decl in
+        match CAst_utils.get_decl_opt_with_decl_ref property_decl_opt with
+        | Some decl ->
+            get_field fields decl
+        | None ->
+            fields )
+    | ObjCIvarDecl (_, name_info, qual_type, _, _) ->
+        let field = get_sil_field name_info qual_type [] in
+        CGeneral_utils.add_no_duplicates_fields field fields
+    | _ ->
+        fields
+  in
+  List.fold ~f:get_field ~init:[] decl_list
 
 
 (* Add potential extra fields defined only in the implementation of the class *)

infer/src/clang/cGeneral_utils.mli

@@ -13,9 +13,10 @@ open! IStd
 
 type var_info = Clang_ast_t.decl_info * Clang_ast_t.qual_type * Clang_ast_t.var_decl_info * bool
 
+val add_no_duplicates_fields : Typ.Struct.field -> Typ.Struct.field list -> Typ.Struct.field list
+
 val append_no_duplicates_fields :
-  (Typ.Fieldname.t * Typ.t * Annot.Item.t) list -> (Typ.Fieldname.t * Typ.t * Annot.Item.t) list
-  -> (Typ.Fieldname.t * Typ.t * Annot.Item.t) list
+  Typ.Struct.field list -> Typ.Struct.field list -> Typ.Struct.field list
 
 val swap_elements_list : 'a list -> 'a list
 

infer/tests/codetoanalyze/objc/errors/Makefile

@@ -94,6 +94,7 @@ SOURCES_ARC = \
   memory_leaks_benchmark/retain_cycle.m \
   memory_leaks_benchmark/retain_cycle2.m \
 	memory_leaks_benchmark/RetainCycleBlocks.m \
+	memory_leaks_benchmark/RetainCyclePropertyInProtocol.m \
   npe/BoxedNumberExample.m \
   npe/ObjCMethodCallInCondition.m \
   npe/UpdateDict.m \

infer/tests/codetoanalyze/objc/errors/memory_leaks_benchmark/RetainCyclePropertyInProtocol.m

@@ -0,0 +1,46 @@
+/*
+ * Copyright (c) 2018 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+#import <Foundation/NSObject.h>
+
+@protocol Delegate
+@property(nonatomic, weak, readwrite) id delegate;
+@end
+
+@interface MyCustomView : NSObject<Delegate>
+- (instancetype)initWithDelegate:(id)delegate;
+@end
+
+@implementation MyCustomView
+@synthesize delegate = _delegate;
+
+- (instancetype)initWithDelegate:(id)delegate {
+  _delegate = delegate;
+  return self;
+}
+
+@end
+
+@interface MyCustomViewController : NSObject
+@property(nonatomic, strong, readwrite) id view;
+@end
+
+@implementation MyCustomViewController
+
+- (void)loadView {
+  MyCustomView* _myView = [[MyCustomView alloc] initWithDelegate:self];
+  self.view = _myView;
+}
+
+@end
+
+int main_good() {
+  MyCustomViewController* controller = [MyCustomViewController new];
+  [controller loadView];
+  return 0;
+}