First approximation of stateless

Reviewed By: jvillard

Differential Revision: D10141376

fbshipit-source-id: a1dbb4c21

infer/src/clang/cPredicates.ml

@@ -499,6 +499,14 @@ let call_instance_method an mname =
       false
 
 
+let adhere_to_protocol an =
+  match an with
+  | Ctl_parser_types.Decl (Clang_ast_t.ObjCInterfaceDecl (_, _, _, _, idi)) ->
+      not (List.is_empty idi.otdi_protocols)
+  | _ ->
+      false
+
+
 let is_objc_extension lcxt =
   CGeneral_utils.is_objc_extension lcxt.CLintersContext.translation_unit_context
 
@@ -527,6 +535,26 @@ let is_qual_type_const an =
       false
 
 
+let objc_class_has_only_one_constructor_method_named an re =
+  let open Clang_ast_t in
+  let is_class_method d =
+    match d with
+    | Clang_ast_t.ObjCMethodDecl (_, _, omdi) ->
+        not omdi.omdi_is_instance_method
+    | _ ->
+        false
+  in
+  match an with
+  | Ctl_parser_types.Decl (ObjCImplementationDecl (_, _, decls, _, _)) -> (
+    match List.filter decls ~f:(fun d -> is_class_method d) with
+    | [n] ->
+        is_objc_class_method_named (Ctl_parser_types.Decl n) re
+    | _ ->
+        false )
+  | _ ->
+      false
+
+
 let has_init_list_const_expr an =
   let rec fold lexp = List.fold ~f:(fun acc e -> is_const_expr' e && acc) ~init:true lexp
   and is_const_expr' exp =
@@ -789,6 +817,26 @@ let is_in_cxx_destructor context name =
       false
 
 
+let cxx_construct_expr_has_no_parameters an =
+  match an with
+  | Ctl_parser_types.Stmt (Clang_ast_t.CXXConstructExpr (_, [], _, _)) ->
+      true
+  | _ ->
+      false
+
+
+let cxx_construct_expr_has_name an name =
+  match an with
+  | Ctl_parser_types.Stmt (Clang_ast_t.CXXConstructExpr (_, _, _, xcei)) -> (
+    match xcei.xcei_decl_ref.dr_name with
+    | Some ni ->
+        ALVar.compare_str_with_alexp ni.ni_name name
+    | _ ->
+        false )
+  | _ ->
+      false
+
+
 let is_in_block context =
   match context.CLintersContext.current_method with Some (BlockDecl _) -> true | _ -> false
 
@@ -930,6 +978,16 @@ let is_receiver_super an =
       false
 
 
+let is_receiver_self an =
+  match an with
+  | Ctl_parser_types.Stmt (Clang_ast_t.ObjCMessageExpr (_, fst_param :: _, _, _)) ->
+      CAst_utils.exists_eventually_st
+        (decl_ref_name ~kind:`ImplicitParam)
+        (ALVar.Const "self") fst_param
+  | _ ->
+      false
+
+
 let captures_cxx_references an = List.length (captured_variables_cxx_ref an) > 0
 
 let is_binop_with_kind an alexp_kind =

infer/src/clang/cPredicates.mli

@@ -196,6 +196,9 @@ val is_objc_category_implementation_on_subclass_of :
  *    inherits from a class whose name matches the provided REGEXP
  *)
 
+val adhere_to_protocol : Ctl_parser_types.ast_node -> bool
+(** true if an objC  class adhere to a protocol *)
+
 val is_objc_protocol_named : Ctl_parser_types.ast_node -> ALVar.alexp -> bool
 (**
  *  Checks if the current node is an ObjCProtocolDecl node
@@ -223,6 +226,11 @@ val is_objc_method_named : Ctl_parser_types.ast_node -> ALVar.alexp -> bool
 val is_objc_constructor : CLintersContext.context -> bool
 (** 'is_in_objc_constructor context' is true if the curent node is within an ObjC constructor *)
 
+val objc_class_has_only_one_constructor_method_named :
+  Ctl_parser_types.ast_node -> ALVar.alexp -> bool
+(** true if an ObjC class has only one class method and is a constructor 
+whose name matches the provided REGEXP *)
+
 val is_objc_dealloc : CLintersContext.context -> bool
 (** 'is_in_objc_dealloc context' is true if the curent node is within an ObjC dealloc method *)
 
@@ -445,11 +453,20 @@ val is_receiver_super : Ctl_parser_types.ast_node -> bool
  *  Matches on [super myMethod];
  *)
 
+val is_receiver_self : Ctl_parser_types.ast_node -> bool
+(**
+ *  Checks if the current node is an ObjCMessageExpr node and has a
+ *    receiver which is equal to 'self'.
+ *)
+
 val is_at_selector_with_name : Ctl_parser_types.ast_node -> ALVar.alexp -> bool
 (** an is an expression @selector with whose name in the language of re *)
 
 val has_visibility_attribute : Ctl_parser_types.ast_node -> ALVar.alexp -> bool
 
+val cxx_construct_expr_has_name : Ctl_parser_types.ast_node -> ALVar.alexp -> bool
+(** true if the node is a CXXConstruct with name matching the provided REGEXP *)
+
 val has_used_attribute : Ctl_parser_types.ast_node -> bool
 
 val iphoneos_target_sdk_version_by_path : CLintersContext.context -> string option
@@ -472,3 +489,6 @@ val is_cxx_copy_constructor : Ctl_parser_types.ast_node -> bool
 
 val is_init_expr_cxx11_constant : Ctl_parser_types.ast_node -> bool
 (** true if the current node is classified as C++11 constant expression by the AST. It works only for VarDecl init expr *)
+
+val cxx_construct_expr_has_no_parameters : Ctl_parser_types.ast_node -> bool
+(** true if a construct expr has no subexpressions *)

infer/src/clang/cTL.ml

@@ -1014,6 +1014,8 @@ let rec eval_Atomic pred_name_ args an lcxt =
       CPredicates.is_global_var an
   | "is_static_local_var", [], an ->
       CPredicates.is_static_local_var an
+  | "adhere_to_protocol", [], an ->
+      CPredicates.adhere_to_protocol an
   | "is_in_block", [], _ ->
       CPredicates.is_in_block lcxt
   | "is_in_cxx_constructor", [name], _ ->
@@ -1066,6 +1068,8 @@ let rec eval_Atomic pred_name_ args an lcxt =
       CPredicates.is_node an nodename
   | "is_objc_constructor", [], _ ->
       CPredicates.is_objc_constructor lcxt
+  | "objc_class_has_only_one_constructor_method_named", [name], an ->
+      CPredicates.objc_class_has_only_one_constructor_method_named an name
   | "is_objc_dealloc", [], _ ->
       CPredicates.is_objc_dealloc lcxt
   | "is_objc_extension", [], _ ->
@@ -1126,6 +1130,8 @@ let rec eval_Atomic pred_name_ args an lcxt =
       CPredicates.is_receiver_class_named lcxt an name
   | "is_receiver_super", [], an ->
       CPredicates.is_receiver_super an
+  | "is_receiver_self", [], an ->
+      CPredicates.is_receiver_self an
   | "iphoneos_target_sdk_version_greater_or_equal", [version], _ ->
       CPredicates.iphoneos_target_sdk_version_greater_or_equal lcxt (ALVar.alexp_to_string version)
   | "method_return_type", [typ], an ->
@@ -1136,6 +1142,8 @@ let rec eval_Atomic pred_name_ args an lcxt =
       CPredicates.using_namespace an namespace
   | "is_at_selector_with_name", [name], an ->
       CPredicates.is_at_selector_with_name an name
+  | "cxx_construct_expr_has_name", [name], an ->
+      CPredicates.cxx_construct_expr_has_name an name
   | "has_type_const_ptr_to_objc_class", [], an ->
       CPredicates.has_type_const_ptr_to_objc_class an
   | "has_type_subprotocol_of", [protname], an ->
@@ -1152,6 +1160,8 @@ let rec eval_Atomic pred_name_ args an lcxt =
       CPredicates.is_cxx_copy_constructor an
   | "is_init_expr_cxx11_constant", [], an ->
       CPredicates.is_init_expr_cxx11_constant an
+  | "cxx_construct_expr_has_no_parameters", [], an ->
+      CPredicates.cxx_construct_expr_has_no_parameters an
   | _ ->
       L.(die ExternalError) "Undefined Predicate or wrong set of arguments: '%s'" pred_name
 

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

@@ -27,4 +27,6 @@ codetoanalyze/objcpp/linters-for-test-only/TestStructFieldChecks.mm, buttonCompo
 codetoanalyze/objcpp/linters-for-test-only/TestStructFieldChecks.mm, buttonComponent, 33, TITLE_NOT_INITIALIZED, no_bucket, WARNING, []
 codetoanalyze/objcpp/linters-for-test-only/TestStructFieldChecks.mm, buttonComponent, 37, TITLE_NOT_INITIALIZED, no_bucket, WARNING, []
 codetoanalyze/objcpp/linters-for-test-only/hash_test.mm, std::hash_NSObject_*__operator(), 12, DISCOURAGED_HASH_METHOD_INVOCATION, no_bucket, WARNING, []
+codetoanalyze/objcpp/linters-for-test-only/stateless.m, Linters_dummy_method, 21, ADHERE_TO_PROTOCOL, no_bucket, WARNING, []
+codetoanalyze/objcpp/linters-for-test-only/stateless.m, Linters_dummy_method, 24, ONLY_ONE_CLASS_METHOD, no_bucket, WARNING, []
 codetoanalyze/objcpp/linters-for-test-only/static.m, objc_block_1, 18, OBJC_BLOCK_CAPTURING_VALUES, no_bucket, WARNING, []

infer/tests/codetoanalyze/objcpp/linters-for-test-only/linters_example.al

@@ -209,3 +209,27 @@ DEFINE-CHECKER OBJC_BLOCK_CAPTURING_VALUES = {
       SET message = "ObjC Block capturing values";
       SET mode = "ON";
 };
+
+DEFINE-CHECKER ADHERE_TO_PROTOCOL = {
+
+  SET report_when =
+  WHEN
+    adhere_to_protocol()
+  HOLDS-IN-NODE ObjCInterfaceDecl;
+
+  SET message = "Found class adhering to protocol";
+  SET mode = "ON";
+
+};
+
+DEFINE-CHECKER ONLY_ONE_CLASS_METHOD = {
+
+  SET report_when =
+       WHEN
+          objc_class_has_only_one_constructor_method_named(REGEXP("newWith.+"))
+       HOLDS-IN-NODE ObjCImplementationDecl;
+
+  SET message = "Found class with only one class method";
+  SET mode = "ON";
+
+};

infer/tests/codetoanalyze/objcpp/linters-for-test-only/stateless.m

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2018-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/Foundation.h>
+
+@interface B : NSObject
+@end
+
+@implementation B
++ (void)newWithB {
+}
+
++ (void)foo {
+}
+
+@end
+
+@interface A<NSObject>
+@end
+
+@implementation A
+
+- (int)foo {
+  return 0;
+}
+
++ (int)newWithBA {
+  return 0;
+}
+
+@end