Do not throw value errors when integers are not a valid value of the proto enum.

PiperOrigin-RevId: 549473332

Author: Xiaofei Wang

pybind11_protobuf/enum_type_caster.h

@@ -59,12 +59,8 @@ struct enum_type_caster {
     base_caster base;
     if (base.load(src, convert)) {
       T v = static_cast<T>(base);
-      if (::google::protobuf::GetEnumDescriptor<EnumType>()->FindValueByNumber(v) ==
-          nullptr) {
-        throw pybind11::value_error("Invalid value " + std::to_string(v) +
-                                    " for ::google::protobuf::Enum " +
-                                    pybind11::type_id<EnumType>());
-      }
+      // Behavior change 2023-07-19: Previously we only accept integers that
+      // are valid values of the enum.
       value = static_cast<EnumType>(v);
       return true;
     }

pybind11_protobuf/tests/proto_enum_test.py

@@ -19,8 +19,7 @@ def test_enum(self):
     self.assertEqual(
         m.adjust_enum(test_pb2.TestMessage.ONE), test_pb2.TestMessage.TWO)
     self.assertEqual(m.adjust_enum(m.ZERO), m.ONE)
-    with self.assertRaises(ValueError):
-      m.adjust_enum(7)
+    self.assertEqual(m.adjust_enum(7), m.ZERO)
     with self.assertRaises(TypeError):
       m.adjust_enum('ZERO')