From 07797410cc506733c1abc0178795205d3dc894a5 Mon Sep 17 00:00:00 2001
From: Ryan Rhee <ryanrhee@fb.com>
Date: Fri, 30 Sep 2016 12:17:57 -0700
Subject: [PATCH] [clang][frontend] Break out objc class inheritance check
 function

Reviewed By: dulmarod

Differential Revision: D3934187

fbshipit-source-id: e23cbcf
---
 infer/src/clang/ComponentKit.ml     | 46 ++++-------------------------
 infer/src/clang/cFrontend_utils.ml  | 17 +++++++++++
 infer/src/clang/cFrontend_utils.mli |  8 +++++
 3 files changed, 31 insertions(+), 40 deletions(-)

diff --git a/infer/src/clang/ComponentKit.ml b/infer/src/clang/ComponentKit.ml
index 95f8fc473..5030f6e2c 100644
--- a/infer/src/clang/ComponentKit.ml
+++ b/infer/src/clang/ComponentKit.ml
@@ -12,52 +12,16 @@ open !Utils
 
 (** Recursively go up the inheritance hierarchy of a given ObjCInterfaceDecl.
     (Returns false on decls other than that one.) *)
-let rec is_component_if decl =
-  match decl with
-  | Some Clang_ast_t.ObjCInterfaceDecl (_, ndi, _, _, _)->
-      let open CFrontend_config in
-      let whitelist = [ckcomponent_cl] in
-      let blacklist = [nsobject_cl; nsproxy_cl] in
-      let in_list some_list = IList.mem string_equal ndi.Clang_ast_t.ni_name some_list in
-      if in_list whitelist then
-        true
-      else if in_list blacklist then
-        false
-      else
-        (match Ast_utils.get_super_if decl with
-         | Some super_decl ->
-             is_component_if (Some super_decl)
-         | None -> false)
-  | _ -> false
-
-
-(** Recursively go up the inheritance hierarchy of a given ObjCInterfaceDecl.
-    (Returns false on decls other than that one.) *)
-let rec is_component_or_controller_if decl =
-  match decl with
-  | Clang_ast_t.ObjCInterfaceDecl (_, ndi, _, _, _)->
-      let open CFrontend_config in
-      let whitelist = [ckcomponent_cl; ckcomponentcontroller_cl] in
-      let blacklist = [nsobject_cl; nsproxy_cl] in
-      let in_list some_list = IList.mem string_equal ndi.Clang_ast_t.ni_name some_list in
-      if in_list whitelist then
-        true
-      else if in_list blacklist then
-        false
-      else
-        (match Ast_utils.get_super_if (Some decl) with
-         | Some super_decl ->
-             is_component_or_controller_if super_decl
-         | None -> false)
-  | _ -> false
+let is_component_or_controller_if decl =
+  let open CFrontend_config in
+  Ast_utils.is_objc_if_descendant decl [ckcomponent_cl; ckcomponentcontroller_cl]
 
 (** True if it's an objc class impl that extends from CKComponent or
     CKComponentController, false otherwise *)
 let rec is_component_or_controller_descendant_impl decl =
   match decl with
   | Clang_ast_t.ObjCImplementationDecl _ ->
-      let super_if = Ast_utils.get_super_if (Some decl) in
-      Option.map_default is_component_or_controller_if false super_if
+      is_component_or_controller_if (Ast_utils.get_super_if (Some decl))
   | Clang_ast_t.LinkageSpecDecl (_, decl_list, _) ->
       contains_ck_impl decl_list
   | _ -> false
@@ -145,6 +109,8 @@ let mutable_local_vars_advice context decl =
 
     Any static function that returns a subclass of CKComponent will be flagged. *)
 let component_factory_function_advice context decl =
+  let is_component_if decl =
+    Ast_utils.is_objc_if_descendant decl [CFrontend_config.ckcomponent_cl] in
 
   let rec type_ptr_to_objc_if type_ptr =
     let typ_opt = Ast_utils.get_desugared_type type_ptr in
diff --git a/infer/src/clang/cFrontend_utils.ml b/infer/src/clang/cFrontend_utils.ml
index 01950eff0..06616e287 100644
--- a/infer/src/clang/cFrontend_utils.ml
+++ b/infer/src/clang/cFrontend_utils.ml
@@ -442,6 +442,23 @@ struct
     let file_opt = (fst decl_info.Clang_ast_t.di_source_range).Clang_ast_t.sl_file in
     opt_equal string_equal file_opt Config.source_file && Option.is_some file_opt
 
+  let rec is_objc_if_descendant if_decl ancestors =
+    match if_decl with
+    | Some Clang_ast_t.ObjCInterfaceDecl (_, ndi, _, _, _)->
+        let open CFrontend_config in
+        let blacklist = [nsobject_cl; nsproxy_cl] in
+        let in_list some_list = IList.mem string_equal ndi.Clang_ast_t.ni_name some_list in
+        if in_list ancestors then
+          true
+        else if in_list blacklist then
+          false
+        else
+          (match get_super_if if_decl with
+           | Some super_decl ->
+               is_objc_if_descendant (Some super_decl) ancestors
+           | None -> false)
+    | _ -> false
+
 (*
   let rec getter_attribute_opt attributes =
     match attributes with
diff --git a/infer/src/clang/cFrontend_utils.mli b/infer/src/clang/cFrontend_utils.mli
index 47b9f4357..5bd63ad15 100644
--- a/infer/src/clang/cFrontend_utils.mli
+++ b/infer/src/clang/cFrontend_utils.mli
@@ -160,6 +160,14 @@ sig
       to the parent decl. *)
   val is_in_main_file : Clang_ast_t.decl -> bool
 
+  (** Recursively go up the inheritance hierarchy of a given ObjCInterfaceDecl.
+      Returns true if the passed in decl is an objc interface decl that's an
+      eventual descendant of one of the classes passed in.
+      Ancestors param is a list of strings that represent the class names.
+      Will short-circuit on NSObject and NSProxy since those are known to be
+      common base classes. *)
+  val is_objc_if_descendant : Clang_ast_t.decl option -> (string) list -> bool
+
 end
 
 module General_utils :