[linters] Take into account the respondsToSelector block in the unavailable api check

Reviewed By: martinoluca

Differential Revision: D4455886

fbshipit-source-id: 58d4d96

infer/lib/linter_rules/linters.al

@@ -208,7 +208,8 @@ DEFINE-CHECKER CXX_REFERENCE_CAPTURED_IN_OBJC_BLOCK = {
 //	DEFINE-CHECKER ctl_unavailable_api_in_supported_ios_sdk_error = {
 //		  SET report_when =
 //			     WHEN
-//					    WITH-TRANSITION PointerToDecl decl_unavailable_in_supported_ios_sdk
+//					    WITH-TRANSITION PointerToDecl
+//                (decl_unavailable_in_supported_ios_sdk AND NOT within_responds_to_selector_block)
 //	         HOLDS-IN-NODE DeclRefExpr, ObjCMessageExpr;
 //
 //		  SET message =

infer/src/clang/CLintersContext.ml

@@ -10,7 +10,7 @@
 open! IStd
 
 type if_context = {
-  in_responds_to_selector_block : string list;
+  within_responds_to_selector_block : string list;
 }
 
 type context = {

infer/src/clang/cFrontend_checkers.ml

@@ -104,7 +104,10 @@ let ctl_unavailable_api_in_supported_ios_sdk_error lctx an =
   let open CTL in
   let condition =
     InNode(["DeclRefExpr"; "ObjCMessageExpr"],
-           EX (Some PointerToDecl, (Atomic ("decl_unavailable_in_supported_ios_sdk", [])))) in
+           EX (Some PointerToDecl, (
+               And
+                 (Atomic ("decl_unavailable_in_supported_ios_sdk", []),
+                  Not (Atomic ("within_responds_to_selector_block", [])))))) in
   let issue_desc =
     { CIssue.name = "UNAVAILABLE_API_IN_SUPPORTED_IOS_SDK";
       severity = Exceptions.Kerror;

infer/src/clang/cFrontend_checkers_main.ml

@@ -41,8 +41,28 @@ let parse_ctl_file linters_files =
        | None -> Logging.out "No linters found.\n");
       In_channel.close inx) linters_files
 
-let compute_if_context _ _ =
-  None (* to be extended *)
+
+let rec get_responds_to_selector stmt =
+  let open Clang_ast_t in
+  match stmt with
+  | ObjCMessageExpr (_, [_; ObjCSelectorExpr (_, _, _, method_name)], _, mdi)
+    when  String.equal mdi.Clang_ast_t.omei_selector "respondsToSelector:" ->
+      [method_name]
+  | BinaryOperator (_, [stmt1;stmt2], _, bo_info)
+    when PVariant.(=) bo_info.Clang_ast_t.boi_kind `LAnd ->
+      List.append (get_responds_to_selector stmt1) (get_responds_to_selector stmt2)
+  | ImplicitCastExpr (_, [stmt], _, _) ->
+      get_responds_to_selector stmt
+  | _ -> []
+
+let compute_if_context (context:CLintersContext.context) stmt =
+  let prev_responds_to_selector =
+    match context.if_context with
+    | Some if_context -> if_context.within_responds_to_selector_block
+    | None -> [] in
+  let within_responds_to_selector_block =
+    List.append (get_responds_to_selector stmt) (prev_responds_to_selector) in
+  Some ({within_responds_to_selector_block} : CLintersContext.if_context)
 
 let is_factory_method (context: CLintersContext.context) decl =
   let interface_decl_opt =

infer/src/clang/cPredicates.ml

@@ -222,3 +222,14 @@ let decl_unavailable_in_supported_ios_sdk decl =
   | Some available_attr_ios_sdk, Some iphoneos_target_sdk_version ->
       Int.equal (Utils.compare_versions available_attr_ios_sdk iphoneos_target_sdk_version) 1
   | _ -> false
+
+let within_responds_to_selector_block (cxt:CLintersContext.context) decl =
+  let open Clang_ast_t in
+  match decl with
+  | ObjCMethodDecl (_, named_decl_info, _) ->
+      (match cxt.if_context with
+       | Some if_context ->
+           let in_selector_block = if_context.within_responds_to_selector_block in
+           List.mem ~equal:String.equal in_selector_block named_decl_info.Clang_ast_t.ni_name
+       | None -> false)
+  | _ -> false

infer/src/clang/cPredicates.mli

@@ -58,3 +58,5 @@ val pp_predicate : Format.formatter -> t -> unit
 val decl_unavailable_in_supported_ios_sdk : Clang_ast_t.decl -> bool
 
 val get_available_attr_ios_sdk : Clang_ast_t.decl -> string option
+
+val within_responds_to_selector_block : CLintersContext.context -> Clang_ast_t.decl -> bool

infer/src/clang/cTL.ml

@@ -417,6 +417,8 @@ let rec eval_Atomic pred_name args an lcxt =
   | "isa", _, Decl _ -> false
   | "decl_unavailable_in_supported_ios_sdk", [], Decl decl ->
       CPredicates.decl_unavailable_in_supported_ios_sdk decl
+  | "within_responds_to_selector_block", [], Decl decl ->
+      CPredicates.within_responds_to_selector_block lcxt decl
   | "decl_unavailable_in_supported_ios_sdk", _, Stmt _ -> false
   | _ -> failwith ("ERROR: Undefined Predicate or wrong set of arguments: " ^ pred_name)
 

infer/tests/codetoanalyze/objc/iosLinters/unavailable_api_allowed_cases.m

@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2017 - 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 <UIKit/UIKit.h>
+
+@interface Unavailable_api_allowed_cases : NSObject
+
+- (void)m NS_AVAILABLE(10_12, 10_0);
+
+- (void)n NS_AVAILABLE(10_12, 10_0);
+
+@end
+
+@implementation Unavailable_api_allowed_cases
+
+- (void)m {
+}
+
+- (void)n {
+}
+
+// no bug
+- (void)with_responds_to_selector:(Unavailable_api_allowed_cases*)a {
+  if ([a respondsToSelector:@selector(m)]) {
+    int x = 1;
+    [a m];
+    x = 3;
+  }
+}
+// no bug
+- (void)with_responds_to_selector:(Unavailable_api_allowed_cases*)a
+                              and:(BOOL)ok {
+  if ([a respondsToSelector:@selector(m)] && ok) {
+    [a m];
+  }
+}
+
+// bug
+- (void)without_responds_to_selector:(Unavailable_api_allowed_cases*)a {
+  [a m];
+}
+
+// bug
+- (void)with_responds_to_selector_in_else:(Unavailable_api_allowed_cases*)a {
+  if ([a respondsToSelector:@selector(m)]) {
+  } else {
+    [a m];
+  }
+}
+
+// no bug
+- (void)with_responds_to_selector_nested_if:(Unavailable_api_allowed_cases*)a {
+  if ([a respondsToSelector:@selector(m)]) {
+    if ([a respondsToSelector:@selector(n)]) {
+      [a m];
+      [a n];
+    }
+  }
+}
+
+// no bug
+- (void)with_responds_to_selector_two_selectors:
+    (Unavailable_api_allowed_cases*)a {
+  if ([a respondsToSelector:@selector(m)] &&
+      [a respondsToSelector:@selector(n)]) {
+    [a m];
+    [a n];
+  }
+}
+
+@end

infer/tests/codetoanalyze/objc/ioslinters/issues.exp

@@ -1,2 +1,4 @@
+codetoanalyze/objc/ioslinters/unavailable_api_allowed_cases.m, Unavailable_api_allowed_cases_with_responds_to_selector_in_else:, 52, UNAVAILABLE_API_IN_SUPPORTED_IOS_SDK, []
+codetoanalyze/objc/ioslinters/unavailable_api_allowed_cases.m, Unavailable_api_allowed_cases_without_responds_to_selector:, 45, UNAVAILABLE_API_IN_SUPPORTED_IOS_SDK, []
 codetoanalyze/objc/ioslinters/unavailable_api_in_supported_ios_sdk.m, OpenURLOptionsFromSourceApplication, 18, UNAVAILABLE_API_IN_SUPPORTED_IOS_SDK, []
 codetoanalyze/objc/ioslinters/unavailable_api_in_supported_ios_sdk.m, Unavailable_api_in_supported_ios_sdk_test:and:, 11, UNAVAILABLE_API_IN_SUPPORTED_IOS_SDK, []