[pulse] Model std::__optional_storage_base::has_value

Summary: Model ` std::__optional_storage_base::has_value` as this is what we see in clang AST when translating  `std::optional::has_value` for libc++. For libstdc++, we get `std::optional::has_value` as expected.

Reviewed By: skcho, jvillard

Differential Revision: D25585543

fbshipit-source-id: b8d9d2902

infer/src/pulse/PulseModels.ml

@@ -1075,14 +1075,14 @@ module ProcNameDispatcher = struct
                  ~desc:"std::optional::optional(std::optional<Value> arg)"
         ; -"std" &:: "optional" &:: "optional" $ capt_arg_payload $+ capt_arg_payload
           $+...$--> Optional.assign_value ~desc:"std::optional::optional(Value arg)"
-        ; -"std" &:: "optional" &:: "operator=" <>$ capt_arg_payload
+        ; -"std" &:: "optional" &:: "operator=" $ capt_arg_payload
           $+ any_arg_of_typ (-"std" &:: "nullopt_t")
           $--> Optional.assign_none ~desc:"std::optional::operator=(None)"
-        ; -"std" &:: "optional" &:: "operator=" <>$ capt_arg_payload
+        ; -"std" &:: "optional" &:: "operator=" $ capt_arg_payload
           $+ capt_arg_payload_of_typ (-"std" &:: "optional")
           $--> Optional.assign_optional_value
                  ~desc:"std::optional::operator=(std::optional<Value> arg)"
-        ; -"std" &:: "optional" &:: "operator=" <>$ capt_arg_payload $+ capt_arg_payload
+        ; -"std" &:: "optional" &:: "operator=" $ capt_arg_payload $+ capt_arg_payload
           $+...$--> Optional.assign_value ~desc:"std::optional::operator=(Value arg)"
         ; -"std" &:: "optional" &:: "emplace<>" $ capt_arg_payload
           $+...$--> Optional.emplace ~desc:"std::optional::emplace()"
@@ -1090,6 +1090,8 @@ module ProcNameDispatcher = struct
           $+...$--> Optional.emplace ~desc:"std::optional::emplace()"
         ; -"std" &:: "optional" &:: "has_value" <>$ capt_arg_payload
           $+...$--> Optional.has_value ~desc:"std::optional::has_value()"
+        ; -"std" &:: "__optional_storage_base" &:: "has_value" $ capt_arg_payload
+          $+...$--> Optional.has_value ~desc:"std::optional::has_value()"
         ; -"std" &:: "optional" &:: "operator_bool" <>$ capt_arg_payload
           $+...$--> Optional.has_value ~desc:"std::optional::operator_bool()"
         ; -"std" &:: "optional" &:: "reset" <>$ capt_arg_payload

infer/tests/codetoanalyze/cpp/pulse/optional.cpp

@@ -238,6 +238,14 @@ int std_none_check_ok() {
   return -1;
 }
 
+int std_none_check_has_value_ok() {
+  std::optional<int> foo{std::nullopt};
+  if (foo.has_value()) {
+    return foo.value();
+  }
+  return -1;
+}
+
 int std_none_no_check_bad() {
   std::optional<int> foo{std::nullopt};
   return foo.value();
@@ -305,6 +313,7 @@ int std_value_or_check_value_ok_FP() {
   }
   return -1;
 }
+
 struct Container final {
   std::vector<int> _vec;
 
@@ -324,3 +333,19 @@ struct Container final {
     return -1;
   }
 };
+
+std::optional<std::string> might_return_none(bool b, std::string x) {
+  if (b) {
+    return std::nullopt;
+  }
+  return x;
+}
+
+std::string reassing_non_empty_ok(const std::string& x) {
+  std::optional<std::string> foo = might_return_none(true, x);
+  if (!foo.has_value()) {
+    foo = x;
+  }
+
+  return foo.value();
+}