[ConfigImpact] Add known cheap functions of System and Number

Reviewed By: ezgicicek

Differential Revision: D27394901

fbshipit-source-id: 3f4af1a24

infer/src/absint/PatternMatch.ml

@@ -109,9 +109,11 @@ module Java = struct
     supertype_exists tenv is_interface (Typ.Name.Java.from_string typename)
 
 
+  let implements_lang class_name = implements ("java.lang." ^ class_name)
+
   let implements_arrays = implements "java.util.Arrays"
 
-  let implements_iterable = implements "java.lang.Iterable"
+  let implements_iterable = implements_lang "Iterable"
 
   let implements_iterator = implements "java.util.Iterator"
 
@@ -121,7 +123,11 @@ module Java = struct
 
   let implements_list = implements "java.util.List"
 
-  let implements_math = implements "java.lang.Math"
+  let implements_math = implements_lang "Math"
+
+  let implements_number = implements_lang "Number"
+
+  let implements_system = implements_lang "System"
 
   let implements_xmob_utils class_name = implements ("com.moblica.common.xmob.utils." ^ class_name)
 
@@ -162,8 +168,6 @@ module Java = struct
 
   let implements_queue = implements "java.util.Queue"
 
-  let implements_lang class_name = implements ("java.lang." ^ class_name)
-
   let implements_google class_name = implements ("com.google." ^ class_name)
 
   let implements_android class_name = implements ("android." ^ class_name)

infer/src/absint/PatternMatch.mli

@@ -95,6 +95,9 @@ module Java : sig
   val implements_nio : string -> Tenv.t -> string -> bool
   (** Check whether class implements a Java nio *)
 
+  val implements_number : Tenv.t -> string -> bool
+  (** Check whether class implements a Java's Number *)
+
   val implements_org_json : string -> Tenv.t -> string -> bool
   (** Check whether class implements a class from Json *)
 
@@ -113,6 +116,9 @@ module Java : sig
   val implements_sparse_float_array : Tenv.t -> string -> bool
   (** Check whether class implements a class of [com.facebook.litho.internal.SparseFloatArray] *)
 
+  val implements_system : Tenv.t -> string -> bool
+  (** Check whether class implements a Java's System *)
+
   val implements_view_group : Tenv.t -> string -> bool
   (** Check whether class implements a class of [android.view.ViewGroup] *)
 

infer/src/checkers/ConfigImpactAnalysis.ml

@@ -375,10 +375,40 @@ module TransferFunctions = struct
     && Procname.get_method pname |> String.equal "booleanValue"
 
 
+  let is_cheap_system_method =
+    let cheap_system_methods =
+      String.Set.of_list
+        [ "clearProperty"
+        ; "console"
+        ; "currentTimeMillis"
+        ; "exit"
+        ; "getEnv"
+        ; "getLogger"
+        ; "getProperties"
+        ; "getProperty"
+        ; "getSecurityManager"
+        ; "identityHashCode​"
+        ; "inheritedChannel"
+        ; "lineSeparator"
+        ; "mapLibraryName​"
+        ; "nanoTime"
+        ; "setErr"
+        ; "setIn"
+        ; "setOut"
+        ; "setProperties"
+        ; "setProperty"
+        ; "setSecurityManager" ]
+    in
+    fun _ method_name -> String.Set.mem cheap_system_methods method_name
+
+
   let is_known_cheap_method =
     let dispatch : (Tenv.t, unit, unit) ProcnameDispatcher.ProcName.dispatcher =
       let open ProcnameDispatcher.ProcName in
-      make_dispatcher [+PatternMatch.Java.implements_math &::.*--> ()]
+      make_dispatcher
+        [ +PatternMatch.Java.implements_math &::.*--> ()
+        ; +PatternMatch.Java.implements_number &::.*--> ()
+        ; +PatternMatch.Java.implements_system &::+ is_cheap_system_method &--> () ]
     in
     fun tenv pname -> dispatch tenv pname |> Option.is_some