[cleanup] generalize PatternMatch.iter_overrides to override_exists

Summary:
The thread-safety and annotation reachibility analyses were defining ugly custom versions of override_exists with refs.
Let's give them a canonical, ref-free version instead.

Reviewed By: jberdine

Differential Revision: D4475777

fbshipit-source-id: 0bb45fc

infer/src/checkers/ThreadSafety.ml

@@ -596,18 +596,13 @@ let process_results_table file_env tab =
   (* TODO (t15588153): clean this up *)
   let is_thread_safe_method pdesc tenv =
     let overrides_thread_safe_method pname tenv =
-      let found = ref false in
-      PatternMatch.proc_iter_overridden_methods
+      PatternMatch.override_exists
         (fun pn ->
-           found :=
-             !found ||
-             Annotations.pname_has_return_annot
-               pn
-               ~attrs_of_pname:Specs.proc_resolve_attributes
-               Annotations.ia_is_thread_safe_method)
-        tenv
-        pname;
-      !found in
+           Annotations.pname_has_return_annot
+             pn
+             ~attrs_of_pname:Specs.proc_resolve_attributes
+             Annotations.ia_is_thread_safe_method)
+        tenv pname in
     Annotations.pdesc_return_annot_ends_with pdesc Annotations.thread_safe_method ||
     overrides_thread_safe_method (Procdesc.get_proc_name pdesc) tenv in
   let should_report ((_, tenv, _, pdesc) as proc_env) =

infer/src/checkers/annotationReachability.ml

@@ -131,14 +131,8 @@ let check_attributes check tenv pname =
   Annotations.pname_has_return_annot pname ~attrs_of_pname:Specs.proc_resolve_attributes check
 
 let method_overrides is_annotated tenv pname =
-  let overrides () =
-    let found = ref false in
-    PatternMatch.proc_iter_overridden_methods
-      (fun pn -> found := is_annotated tenv pn)
-      tenv pname;
-    !found in
   is_annotated tenv pname ||
-  overrides ()
+  PatternMatch.override_exists (fun pn -> is_annotated tenv pn) tenv pname
 
 let method_has_annot annot tenv pname =
   let has_annot ia = Annotations.ia_ends_with ia annot.Annot.class_name in
@@ -366,8 +360,7 @@ module Interprocedural = struct
         Reporting.log_error proc_name ~loc exn in
 
     if expensive then
-      PatternMatch.proc_iter_overridden_methods
-        check_expensive_subtyping_rules tenv proc_name;
+      PatternMatch.override_iter check_expensive_subtyping_rules tenv proc_name;
 
     let report_src_snk_paths call_map (src_annot_list, (snk_annot: Annot.t)) =
       let extract_calls_with_annot annot call_map =

infer/src/checkers/patternMatch.ml

@@ -327,33 +327,28 @@ let proc_calls resolve_attributes pdesc filter : (Procname.t * ProcAttributes.t)
   IList.iter do_node nodes;
   IList.rev !res
 
-
-(** Iterate over all the methods overridden by the procedure.
-    Only Java supported at the moment. *)
-let proc_iter_overridden_methods f tenv proc_name =
-  let do_super_type tenv super_class_name =
+let override_exists f tenv proc_name =
+  let super_type_exists tenv super_class_name =
     let super_proc_name =
       Procname.replace_class proc_name (Typename.name super_class_name) in
     match Tenv.lookup tenv super_class_name with
     | Some ({ methods }) ->
         let is_override pname =
-          Procname.equal pname super_proc_name &&
-          not (Procname.is_constructor pname) in
-        IList.iter
-          (fun pname ->
-             if is_override pname
-             then f pname)
-          methods
-    | _ -> () in
-
+          Procname.equal pname super_proc_name && not (Procname.is_constructor pname) in
+        IList.exists (fun pname -> is_override pname && f pname) methods
+    | _ ->
+        false in
   match proc_name with
   | Procname.Java proc_name_java ->
       let type_name = Typename.Java.from_string (Procname.java_get_class_name proc_name_java) in
-      IList.iter
-        (do_super_type tenv)
+      IList.exists
+        (super_type_exists tenv)
         (type_get_direct_supertypes tenv (Typ.Tstruct type_name))
   | _ ->
-      () (* Only java supported at the moment *)
+      false (* Only java supported at the moment *)
+
+let override_iter f tenv proc_name =
+  ignore(override_exists (fun pname -> f pname; false) tenv proc_name)
 
 (** return the set of instance fields that are assigned to a null literal in [procdesc] *)
 let get_fields_nullified procdesc =

infer/src/checkers/patternMatch.mli

@@ -82,9 +82,14 @@ val proc_calls :
   (Procname.t -> ProcAttributes.t -> bool) ->
   (Procname.t * ProcAttributes.t) list
 
-(** Iterate over all the methods overridden by the procedure.
-    Only Java supported at the moment. *)
-val proc_iter_overridden_methods : (Procname.t -> unit) -> Tenv.t -> Procname.t -> unit
+(** Return true if applying the given predicate to an override of [procname] returns [true]. Note
+    that this does apply the predicate to [procname] itself. For the moment, this only works for
+    Java *)
+val override_exists : (Procname.t -> bool) -> Tenv.t -> Procname.t -> bool
+
+(** Apply the given predicate to each override of [procname]. Notet hat this does apply the
+    predicate to [procname] itself. For the moment, this only works for Java *)
+val override_iter : (Procname.t -> unit) -> Tenv.t -> Procname.t -> unit
 
 val type_get_annotation : Tenv.t -> Typ.t -> Annot.Item.t option
 

infer/src/eradicate/eradicateChecks.ml

@@ -554,4 +554,4 @@ let check_overridden_annotations
     | None ->
         () in
 
-  PatternMatch.proc_iter_overridden_methods check tenv proc_name
+  PatternMatch.override_iter check tenv proc_name