Fix detection of return type for instancetype when using NS_ASSUME_NONNUL

Reviewed By: jvillard

Differential Revision: D15317686

fbshipit-source-id: a13520499

infer/src/clang/cType_to_sil_type.ml

@@ -100,10 +100,11 @@ let rec build_array_type translate_decl tenv (qual_type : Clang_ast_t.qual_type)
 
 
 and type_desc_of_attr_type translate_decl tenv type_info attr_info =
-  match type_info.Clang_ast_t.ti_desugared_type with
+  let open Clang_ast_t in
+  match type_info.ti_desugared_type with
   | Some type_ptr -> (
     match CAst_utils.get_type type_ptr with
-    | Some (Clang_ast_t.ObjCObjectPointerType (_, qual_type)) ->
+    | Some (ObjCObjectPointerType (_, qual_type)) ->
         let typ = qual_type_to_sil_type translate_decl tenv qual_type in
         Typ.Tptr (typ, pointer_attribute_of_objc_attribute attr_info)
     | _ ->

infer/src/clang/ctl_parser_types.ml

@@ -511,6 +511,12 @@ and c_type_equal c_type abs_ctype =
   match (c_type, abs_ctype) with
   | BuiltinType (_, bi), BuiltIn abi ->
       builtin_equal bi abi
+  | BuiltinType (_, `ObjCId), TypeName ae when ALVar.compare_str_with_alexp "instancetype" ae ->
+      (* This is a special case where coming from an  AttributedType with {ati_attr_kind=`Nonnull} where the 
+  compiler change 'instancetype' to ObjCId *)
+      L.(debug Linters Medium)
+        "@\n Special Case when comaping BuiltInType(ObjcId) and TypeName(instancetype)\n" ;
+      true
   | TypedefType (_, tdi), BuiltIn _ ->
       check_type_ptr tdi.tti_child_type.qt_type_ptr abs_ctype
   | PointerType _, BuiltIn _ | PointerType _, Pointer _ | ObjCObjectPointerType _, Pointer _ ->
@@ -522,6 +528,8 @@ and c_type_equal c_type abs_ctype =
   | FunctionProtoType (_, {fti_return_type= qt}, _), TypeName _
   | ObjCObjectPointerType (_, qt), _ ->
       check_type_ptr qt.qt_type_ptr abs_ctype
+  | ObjCObjectType (_, ooti), TypeName _ ->
+      check_type_ptr ooti.ooti_base_type abs_ctype
   | ObjCObjectType _, ObjCGenProt _ ->
       objc_object_type_equal c_type abs_ctype
   | ObjCInterfaceType (_, pointer), TypeName ae ->
@@ -554,6 +562,8 @@ and c_type_equal c_type abs_ctype =
   | TypedefType (ti, _), ObjCGenProt _
   | AttributedType (ti, _), Pointer _ -> (
     match ti.ti_desugared_type with Some dt -> check_type_ptr dt abs_ctype | None -> false )
+  | AttributedType (ti, _), TypeName _ -> (
+    match ti.ti_desugared_type with Some dt -> check_type_ptr dt abs_ctype | None -> false )
   | _, _ ->
       display_equality_warning () ; false
 

infer/tests/codetoanalyze/objc/linters-for-test-only/issues.exp

@@ -241,6 +241,9 @@ codetoanalyze/objc/linters-for-test-only/implicit_cast.c, main, 9, TEST_IMPLICIT
 codetoanalyze/objc/linters-for-test-only/implicit_cast.c, main, 9, TEST_VAR_TYPE_CHECK, no_bucket, WARNING, []
 codetoanalyze/objc/linters-for-test-only/namespace.mm, Linters_dummy_method, 7, TEST_DEFINE_NAMESPACE, no_bucket, WARNING, []
 codetoanalyze/objc/linters-for-test-only/namespace.mm, Linters_dummy_method, 15, TEST_USING_NAMESPACE, no_bucket, WARNING, []
+codetoanalyze/objc/linters-for-test-only/ns_assume_nonnull.m, Blah::someMethod, 14, TEST_INSTANCE_TYPE, no_bucket, WARNING, []
+codetoanalyze/objc/linters-for-test-only/ns_assume_nonnull.m, Blah::someMethod, 20, TEST_INSTANCE_TYPE, no_bucket, WARNING, []
+codetoanalyze/objc/linters-for-test-only/ns_assume_nonnull.m, Blah::someMethod, 20, TEST_IS_METHOD_EXPOSED, no_bucket, WARNING, []
 codetoanalyze/objc/linters-for-test-only/protocols.m, Foo::newWithA, 22, TEST_INSTANCE_TYPE, no_bucket, WARNING, []
 codetoanalyze/objc/linters-for-test-only/protocols.m, Foo::newWithA, 22, TEST_PROTOCOL_TYPE_INHERITANCE, no_bucket, WARNING, []
 codetoanalyze/objc/linters-for-test-only/protocols.m, Foo::newWithB, 23, TEST_INSTANCE_TYPE, no_bucket, WARNING, []

infer/tests/codetoanalyze/objc/linters-for-test-only/ns_assume_nonnull.m

@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2019-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#import <Foundation/NSObject.h>
+
+NS_ASSUME_NONNULL_BEGIN
+
+@interface Blah : NSObject
+
++ (instancetype)someMethod;
+
+@end
+
+@implementation Blah
+
++ (instancetype)someMethod {
+  return nil;
+}
+
+@end
+
+NS_ASSUME_NONNULL_END