Merge pull request #1363 from neild/jsonnull

jsonpb: accept 'null' as a valid representation of NullValue in unmarshal
diff --git a/internal/testprotos/jsonpb_proto/test2.pb.go b/internal/testprotos/jsonpb_proto/test2.pb.go
index a27dc0c..1dc0f8a 100644
--- a/internal/testprotos/jsonpb_proto/test2.pb.go
+++ b/internal/testprotos/jsonpb_proto/test2.pb.go
@@ -586,6 +586,7 @@
 	//	*MsgWithOneof_Country
 	//	*MsgWithOneof_HomeAddress
 	//	*MsgWithOneof_MsgWithRequired
+	//	*MsgWithOneof_NullValue
 	Union                isMsgWithOneof_Union `protobuf_oneof:"union"`
 	XXX_NoUnkeyedLiteral struct{}             `json:"-"`
 	XXX_unrecognized     []byte               `json:"-"`
@@ -641,6 +642,10 @@
 	MsgWithRequired *MsgWithRequired `protobuf:"bytes,5,opt,name=msg_with_required,json=msgWithRequired,oneof"`
 }
 
+type MsgWithOneof_NullValue struct {
+	NullValue structpb.NullValue `protobuf:"varint,6,opt,name=null_value,json=nullValue,enum=google.protobuf.NullValue,oneof"`
+}
+
 func (*MsgWithOneof_Title) isMsgWithOneof_Union() {}
 
 func (*MsgWithOneof_Salary) isMsgWithOneof_Union() {}
@@ -651,6 +656,8 @@
 
 func (*MsgWithOneof_MsgWithRequired) isMsgWithOneof_Union() {}
 
+func (*MsgWithOneof_NullValue) isMsgWithOneof_Union() {}
+
 func (m *MsgWithOneof) GetUnion() isMsgWithOneof_Union {
 	if m != nil {
 		return m.Union
@@ -693,6 +700,13 @@
 	return nil
 }
 
+func (m *MsgWithOneof) GetNullValue() structpb.NullValue {
+	if x, ok := m.GetUnion().(*MsgWithOneof_NullValue); ok {
+		return x.NullValue
+	}
+	return structpb.NullValue_NULL_VALUE
+}
+
 // XXX_OneofWrappers is for the internal use of the proto package.
 func (*MsgWithOneof) XXX_OneofWrappers() []interface{} {
 	return []interface{}{
@@ -701,6 +715,7 @@
 		(*MsgWithOneof_Country)(nil),
 		(*MsgWithOneof_HomeAddress)(nil),
 		(*MsgWithOneof_MsgWithRequired)(nil),
+		(*MsgWithOneof_NullValue)(nil),
 	}
 }
 
@@ -1177,100 +1192,102 @@
 func init() { proto.RegisterFile("jsonpb_proto/test2.proto", fileDescriptor_50cab1d8463dea41) }
 
 var fileDescriptor_50cab1d8463dea41 = []byte{
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+	0x15, 0xf7, 0xf1, 0x37, 0xe9, 0x58, 0x44, 0xcf, 0x1d, 0x1e, 0x4c, 0x39, 0x9f, 0x16, 0xd9, 0x11,
+	0x42, 0xe3, 0x6a, 0x72, 0x94, 0xb0, 0xb9, 0xe1, 0x1d, 0x7e, 0xb4, 0x09, 0xa5, 0x95, 0x48, 0x54,
+	0xce, 0x99, 0xc5, 0x1f, 0x6d, 0xe2, 0x52, 0x89, 0xea, 0x42, 0x59, 0xf4, 0x87, 0x9b, 0xa8, 0xca,
+	0xcb, 0x4c, 0xaa, 0xa4, 0x9c, 0xdd, 0x64, 0xff, 0x4e, 0x24, 0xb3, 0x59, 0x26, 0xa4, 0xc1, 0xbb,
+	0xff, 0x69, 0x40, 0xf3, 0x3c, 0x2f, 0x67, 0x45, 0x46, 0x3e, 0x80, 0x26, 0x1f, 0x8d, 0x39, 0x2f,
+	0x42, 0x27, 0x72, 0x7a, 0x6d, 0xea, 0xf3, 0x13, 0xce, 0x0b, 0xf2, 0x10, 0x5a, 0x7c, 0x94, 0x33,
+	0x75, 0x1c, 0x87, 0x6e, 0xe4, 0xf4, 0x7c, 0xda, 0xe4, 0x5f, 0xe9, 0x11, 0xf9, 0x08, 0x3a, 0x16,
+	0x18, 0x49, 0x25, 0x42, 0x0f, 0xc1, 0xc0, 0x80, 0xe7, 0x4a, 0x2c, 0x84, 0xc3, 0x41, 0xd8, 0x88,
+	0x9c, 0x9e, 0x67, 0x84, 0xc3, 0xc1, 0x42, 0x38, 0x1c, 0xa0, 0xd0, 0x47, 0x30, 0x30, 0xa0, 0x16,
+	0x1e, 0x40, 0x9b, 0x8f, 0x2a, 0xb3, 0x64, 0x33, 0x72, 0x7a, 0x7b, 0xb4, 0xc5, 0x5f, 0xe3, 0x90,
+	0x44, 0xb0, 0x5b, 0x43, 0xa8, 0x6d, 0x21, 0x0c, 0x16, 0x5e, 0x13, 0x0f, 0x07, 0x61, 0x3b, 0x72,
+	0x7a, 0x0d, 0x2b, 0x1e, 0x0e, 0x96, 0x62, 0xbb, 0x70, 0x80, 0x30, 0x58, 0x78, 0x21, 0x96, 0x66,
+	0x65, 0x88, 0x9c, 0xde, 0x3d, 0xda, 0xe2, 0xe7, 0x2b, 0x2b, 0xcb, 0xe5, 0xca, 0x1d, 0x84, 0xc1,
+	0xc2, 0x6b, 0xe2, 0xe1, 0x20, 0xdc, 0x8d, 0x9c, 0x1e, 0xb1, 0xe2, 0x7a, 0x65, 0xb9, 0x5c, 0x79,
+	0x0f, 0x61, 0xb0, 0xf0, 0xe2, 0xb0, 0x26, 0x05, 0x4f, 0x54, 0x78, 0x27, 0x72, 0x7a, 0x2e, 0x6d,
+	0xf2, 0xe7, 0x7a, 0x64, 0x0e, 0x0b, 0x01, 0x54, 0xde, 0x45, 0x30, 0x30, 0xe0, 0x62, 0xd5, 0x94,
+	0x57, 0xe3, 0x22, 0x0b, 0xf7, 0x23, 0xa7, 0xe7, 0xd0, 0x16, 0x7f, 0x86, 0x43, 0xb3, 0xaa, 0x81,
+	0x50, 0x7b, 0x0f, 0x61, 0xb0, 0xf0, 0x72, 0xcb, 0x4a, 0xe4, 0x6c, 0x1a, 0x92, 0xc8, 0xe9, 0x05,
+	0x7a, 0xcb, 0x38, 0x34, 0x1b, 0x1a, 0xcf, 0x55, 0x26, 0xc3, 0xfb, 0x91, 0xd3, 0xdb, 0xa5, 0x4d,
+	0x7e, 0xa2, 0x47, 0xdd, 0x7f, 0x38, 0x00, 0x67, 0x9c, 0x3d, 0xcf, 0x59, 0xae, 0x32, 0x49, 0xee,
+	0x83, 0x3f, 0x19, 0xb1, 0x84, 0x61, 0x68, 0x5c, 0xda, 0x98, 0x9c, 0x25, 0x4c, 0x47, 0x69, 0x32,
+	0x9a, 0xe5, 0x6c, 0x82, 0x91, 0x71, 0xa9, 0x3f, 0xf9, 0x6d, 0xce, 0x26, 0x66, 0x9a, 0xe9, 0x69,
+	0xcf, 0x4e, 0x9f, 0xe9, 0xe9, 0xfb, 0xe0, 0xa7, 0x68, 0xd1, 0xc0, 0x0d, 0x36, 0x52, 0x6b, 0x91,
+	0x1a, 0x0b, 0x1f, 0x67, 0xfd, 0xb4, 0xb6, 0x48, 0x8d, 0x45, 0xd3, 0x4e, 0x6b, 0x8b, 0xee, 0xbf,
+	0x5d, 0x68, 0xd1, 0x6c, 0x96, 0x25, 0x4a, 0x6a, 0x8a, 0xa8, 0x73, 0xec, 0xe9, 0x1c, 0x8b, 0x3a,
+	0xc7, 0x62, 0x91, 0x63, 0x4f, 0xe7, 0x58, 0x98, 0x1c, 0xd7, 0xc0, 0x70, 0x10, 0x7a, 0x91, 0xa7,
+	0x73, 0x2a, 0x4c, 0x4e, 0x0f, 0xa0, 0x2d, 0xea, 0x1c, 0x36, 0x22, 0x4f, 0xe7, 0x50, 0xd8, 0x1c,
+	0x2e, 0xa0, 0xe1, 0x20, 0xf4, 0x23, 0x4f, 0xa7, 0x4c, 0xd8, 0x94, 0x21, 0x24, 0xeb, 0xf4, 0x7a,
+	0x3a, 0x43, 0xe2, 0x7c, 0x45, 0x65, 0x13, 0xd2, 0x8a, 0x3c, 0x9d, 0x10, 0x61, 0x13, 0x82, 0x9b,
+	0x30, 0xf5, 0x6f, 0x47, 0x9e, 0xae, 0xbf, 0x30, 0xf5, 0x47, 0x8d, 0xad, 0x6f, 0x10, 0x79, 0xba,
+	0xbe, 0xc2, 0xd6, 0xd7, 0xd8, 0x99, 0xea, 0x41, 0xe4, 0xe9, 0xea, 0x89, 0x65, 0xf5, 0x84, 0xad,
+	0x5e, 0x27, 0xf2, 0x74, 0xf5, 0x84, 0xa9, 0xde, 0xff, 0x5d, 0x68, 0xbe, 0xc9, 0xd3, 0x69, 0xa6,
+	0xc8, 0x11, 0xf8, 0x17, 0xbc, 0xe0, 0x02, 0x2b, 0x77, 0x27, 0x3e, 0xe8, 0xaf, 0x74, 0xac, 0xbe,
+	0xe1, 0xf4, 0x9f, 0x6a, 0x02, 0x35, 0x3c, 0x12, 0x6b, 0x53, 0x23, 0xd1, 0x27, 0x78, 0xab, 0xa4,
+	0x29, 0xf0, 0x2f, 0xf9, 0x14, 0x9a, 0x12, 0xdb, 0x0b, 0xbe, 0x4f, 0x9d, 0xf8, 0xfe, 0x9a, 0xc4,
+	0x74, 0x1e, 0x6a, 0x29, 0xa4, 0x6f, 0xce, 0x07, 0xe9, 0x7a, 0xdb, 0x37, 0xd0, 0xf5, 0xa1, 0x59,
+	0x7e, 0x4b, 0x98, 0xa2, 0x87, 0x0f, 0xd0, 0xfd, 0xc1, 0x1a, 0xdd, 0x06, 0x82, 0xd6, 0x24, 0xf2,
+	0x19, 0x04, 0x62, 0x54, 0x2b, 0x3e, 0xc0, 0x05, 0xb6, 0x2b, 0xda, 0xc2, 0xfe, 0xea, 0x7e, 0x02,
+	0xbe, 0x79, 0x90, 0x16, 0x78, 0xf4, 0xf4, 0xd9, 0xfe, 0x0e, 0x09, 0xc0, 0xff, 0x35, 0x3d, 0x3d,
+	0x3d, 0xdb, 0x77, 0x48, 0x1b, 0x1a, 0x27, 0xdf, 0xbc, 0x3e, 0xdd, 0x77, 0xbb, 0xff, 0x72, 0xa1,
+	0xf1, 0x32, 0x99, 0x49, 0xf2, 0x2b, 0xe8, 0x94, 0x2b, 0xbd, 0xcd, 0xc1, 0x45, 0xa2, 0xb5, 0x45,
+	0x34, 0xaf, 0xff, 0xb2, 0xee, 0x76, 0xa7, 0x4c, 0x89, 0x39, 0x0d, 0xca, 0x45, 0xf7, 0x7b, 0x0e,
+	0x7b, 0x25, 0xc6, 0xb7, 0x3e, 0x09, 0x17, 0x3d, 0xba, 0x5b, 0x3c, 0x74, 0xae, 0xcd, 0x51, 0x18,
+	0x97, 0x4e, 0xb9, 0x9c, 0x39, 0xfc, 0x25, 0xdc, 0x59, 0x5f, 0x84, 0xec, 0x83, 0xf7, 0xa7, 0x6c,
+	0x8e, 0xe5, 0xf6, 0xa8, 0xfe, 0x49, 0x1e, 0x80, 0x7f, 0x99, 0x14, 0x55, 0x86, 0xaf, 0x69, 0x40,
+	0xcd, 0xe0, 0x89, 0xfb, 0x0b, 0xe7, 0xf0, 0x1c, 0xf6, 0x37, 0xed, 0x57, 0xf5, 0x6d, 0xa3, 0xff,
+	0xe9, 0xaa, 0xfe, 0x86, 0x6a, 0x2d, 0x4d, 0xbb, 0xff, 0x74, 0x61, 0xf7, 0xa5, 0x9c, 0xbe, 0xc9,
+	0xd5, 0xdb, 0x6f, 0x59, 0xc6, 0x27, 0xe4, 0x43, 0xf0, 0x55, 0xae, 0x8a, 0x0c, 0x3d, 0x83, 0x17,
+	0x3b, 0xd4, 0x0c, 0x49, 0x08, 0x4d, 0x99, 0x14, 0x89, 0x98, 0xa3, 0xb1, 0xf7, 0x62, 0x87, 0xda,
+	0x31, 0x39, 0x84, 0xd6, 0x53, 0x5e, 0xe9, 0xed, 0x60, 0x0f, 0xd1, 0x9a, 0x7a, 0x82, 0x7c, 0x0c,
+	0xbb, 0x6f, 0x79, 0x99, 0x8d, 0x92, 0x34, 0x15, 0x99, 0x94, 0xd8, 0x4e, 0x34, 0xa1, 0xa3, 0x67,
+	0xbf, 0x34, 0x93, 0xe4, 0x37, 0x70, 0xaf, 0x94, 0xd3, 0xd1, 0xbb, 0x5c, 0xbd, 0x1d, 0x89, 0xec,
+	0xcf, 0x55, 0x2e, 0xb2, 0x14, 0x5b, 0x4c, 0x27, 0x7e, 0xb4, 0x7e, 0xc4, 0x66, 0xa3, 0xd4, 0x72,
+	0x5e, 0xec, 0xd0, 0xbb, 0xe5, 0xfa, 0x14, 0xf9, 0x1c, 0x80, 0x55, 0x45, 0x31, 0x32, 0x67, 0xd0,
+	0xc4, 0xd7, 0xe8, 0xb0, 0x6f, 0x6e, 0xdc, 0x7e, 0x7d, 0xe3, 0xf6, 0xcf, 0xaa, 0xa2, 0xf8, 0x9d,
+	0x66, 0xbc, 0xd8, 0xa1, 0x01, 0xab, 0x07, 0x27, 0x2d, 0xf0, 0x2b, 0x96, 0x73, 0xd6, 0xfd, 0x31,
+	0x34, 0x68, 0x96, 0x14, 0xcb, 0x62, 0x38, 0xa6, 0xb3, 0xe1, 0xe0, 0x71, 0xbb, 0x9d, 0xee, 0x5f,
+	0x5d, 0x5d, 0x5d, 0xb9, 0xdd, 0xbf, 0x3b, 0xfa, 0xd9, 0xf5, 0x99, 0xbe, 0x27, 0x8f, 0x20, 0xc8,
+	0xcb, 0x64, 0x9a, 0x33, 0x7d, 0x46, 0x86, 0xbf, 0x9c, 0x58, 0x6a, 0xe2, 0x33, 0xb8, 0x23, 0xb2,
+	0xa4, 0x18, 0x65, 0xef, 0x55, 0xc6, 0x64, 0xce, 0x19, 0xb9, 0xb7, 0x11, 0xf8, 0xa4, 0x08, 0xff,
+	0xb2, 0xe5, 0xdd, 0xb1, 0x0b, 0xd1, 0x3d, 0x2d, 0x3f, 0xad, 0xd5, 0xdd, 0xff, 0xf9, 0x00, 0x5f,
+	0x33, 0xfe, 0x8e, 0xbd, 0x9a, 0xcf, 0x32, 0x49, 0x7e, 0x04, 0x6e, 0xc2, 0xf0, 0xc2, 0xd2, 0xfa,
+	0xcd, 0x07, 0xff, 0x92, 0xcd, 0xa9, 0x9b, 0x30, 0xf2, 0x29, 0x78, 0x69, 0x65, 0xda, 0x4c, 0x27,
+	0x3e, 0xb8, 0x46, 0x7b, 0x66, 0x3f, 0x78, 0xa8, 0x66, 0x91, 0x9f, 0x80, 0x2b, 0x15, 0xde, 0x9f,
+	0x9d, 0xf8, 0xe1, 0x35, 0xee, 0x39, 0x7e, 0xfc, 0x50, 0x57, 0x2a, 0xf2, 0x18, 0x5c, 0x25, 0x6d,
+	0xf0, 0xae, 0x1f, 0xfa, 0xab, 0xfa, 0x3b, 0x88, 0xba, 0x4a, 0x6a, 0x6e, 0x71, 0x89, 0x77, 0xe7,
+	0x36, 0xee, 0x37, 0xb9, 0x54, 0x58, 0x13, 0xea, 0x16, 0x97, 0xa4, 0x07, 0xde, 0x65, 0x52, 0xe0,
+	0x5d, 0xda, 0x89, 0x3f, 0xbc, 0x46, 0x36, 0x44, 0x4d, 0x21, 0x7d, 0xf0, 0xd2, 0x71, 0x81, 0x39,
+	0xd4, 0xe1, 0xb9, 0xf6, 0x5c, 0xd8, 0xa5, 0x2d, 0x3f, 0x1d, 0x17, 0xe4, 0x67, 0xe0, 0x4d, 0x0a,
+	0x85, 0xb1, 0xec, 0xc4, 0x3f, 0xb8, 0xc6, 0xc7, 0x7e, 0x6f, 0xe9, 0x93, 0x42, 0x69, 0x7a, 0x8e,
+	0xd7, 0xcb, 0x76, 0x3a, 0xbe, 0xdb, 0x96, 0x9e, 0x0f, 0x07, 0x7a, 0x37, 0xd5, 0x70, 0x80, 0x29,
+	0xdc, 0xb6, 0x9b, 0xd7, 0xab, 0xfc, 0x6a, 0x38, 0x40, 0xfb, 0xe3, 0x18, 0xbf, 0xa0, 0x6e, 0xb0,
+	0x3f, 0x8e, 0x6b, 0xfb, 0xe3, 0x18, 0xed, 0x8f, 0x63, 0xfc, 0xa4, 0xba, 0xc9, 0x7e, 0xc1, 0xaf,
+	0x90, 0xdf, 0xc0, 0x3b, 0x38, 0xb8, 0xe1, 0xd0, 0x75, 0x73, 0x31, 0x74, 0xe4, 0x69, 0x7f, 0xdd,
+	0x30, 0xe1, 0x06, 0x7f, 0x73, 0xaf, 0x59, 0x7f, 0xa9, 0x04, 0xf9, 0x0c, 0xfc, 0xfa, 0x7e, 0xdb,
+	0xfe, 0x00, 0x78, 0xdf, 0x19, 0x81, 0x61, 0x76, 0x3f, 0x86, 0xbb, 0x1b, 0x2f, 0xb5, 0x6e, 0x69,
+	0xa6, 0x4d, 0xbb, 0xbd, 0x00, 0x7d, 0xbb, 0xff, 0x75, 0xe1, 0xa1, 0x65, 0x7d, 0xc5, 0xd2, 0x5c,
+	0x64, 0x17, 0x6a, 0xc1, 0xfe, 0x39, 0x34, 0x64, 0x35, 0x2e, 0x6d, 0x92, 0x6f, 0x6d, 0x17, 0x14,
+	0x99, 0xe4, 0x5b, 0x08, 0xca, 0x64, 0x36, 0x9a, 0xe4, 0x59, 0x91, 0xda, 0x46, 0x1e, 0x6f, 0x93,
+	0x6d, 0x2e, 0xa5, 0x1b, 0xfc, 0x73, 0x2d, 0x32, 0x8d, 0xbd, 0x5d, 0xda, 0x21, 0xf9, 0x02, 0x3a,
+	0xb2, 0xc8, 0x2f, 0x32, 0x6b, 0xe9, 0xa1, 0xe5, 0xed, 0x3b, 0x01, 0x14, 0xa0, 0xfc, 0xf0, 0xf7,
+	0xb0, 0xb7, 0xe6, 0xbc, 0xda, 0xd3, 0x03, 0xd3, 0xd3, 0xe3, 0xf5, 0x9e, 0x7e, 0xbb, 0xf7, 0x4a,
+	0x73, 0x7f, 0x0c, 0x0f, 0x36, 0x50, 0xac, 0x00, 0x21, 0xd0, 0x18, 0xcf, 0x95, 0xc4, 0x33, 0xde,
+	0xa5, 0xf8, 0xbb, 0xfb, 0x0c, 0xc8, 0x06, 0xf7, 0xcd, 0xd7, 0xaf, 0xea, 0x08, 0x68, 0xe2, 0xf7,
+	0x89, 0xc0, 0x93, 0x4f, 0xa0, 0xc1, 0x92, 0x32, 0xdb, 0xd6, 0xd2, 0xfe, 0x8a, 0xcf, 0x83, 0xf0,
+	0x93, 0xa7, 0xd0, 0xc8, 0xde, 0xab, 0x72, 0x1b, 0xed, 0x6f, 0xdf, 0xa7, 0x90, 0x5a, 0x7c, 0xf2,
+	0xc5, 0x1f, 0x3e, 0x9f, 0xe6, 0xea, 0x6d, 0x35, 0xee, 0x5f, 0xf0, 0xf2, 0x68, 0xca, 0x8b, 0x84,
+	0x4d, 0x97, 0xff, 0x54, 0xe5, 0x4c, 0x65, 0x82, 0x25, 0x05, 0xfe, 0x07, 0x88, 0xb3, 0xf2, 0x68,
+	0xf5, 0x3f, 0xc3, 0xef, 0x02, 0x00, 0x00, 0xff, 0xff, 0x5b, 0xac, 0xa6, 0xa5, 0x28, 0x0e, 0x00,
+	0x00,
 }
diff --git a/internal/testprotos/jsonpb_proto/test2.proto b/internal/testprotos/jsonpb_proto/test2.proto
index d34dc33..f41c0ec 100644
--- a/internal/testprotos/jsonpb_proto/test2.proto
+++ b/internal/testprotos/jsonpb_proto/test2.proto
@@ -91,6 +91,7 @@
     string Country = 3;
     string home_address = 4;
     MsgWithRequired msg_with_required = 5;
+    google.protobuf.NullValue null_value = 6;
   }
 }
 
diff --git a/jsonpb/decode.go b/jsonpb/decode.go
index 60e82ca..6c16c25 100644
--- a/jsonpb/decode.go
+++ b/jsonpb/decode.go
@@ -386,8 +386,14 @@
 }
 
 func isSingularWellKnownValue(fd protoreflect.FieldDescriptor) bool {
+	if fd.Cardinality() == protoreflect.Repeated {
+		return false
+	}
 	if md := fd.Message(); md != nil {
-		return md.FullName() == "google.protobuf.Value" && fd.Cardinality() != protoreflect.Repeated
+		return md.FullName() == "google.protobuf.Value"
+	}
+	if ed := fd.Enum(); ed != nil {
+		return ed.FullName() == "google.protobuf.NullValue"
 	}
 	return false
 }
diff --git a/jsonpb/json_test.go b/jsonpb/json_test.go
index a98ad16..3942773 100644
--- a/jsonpb/json_test.go
+++ b/jsonpb/json_test.go
@@ -441,6 +441,7 @@
 		`{"mBoolSimple":{"true":{"oInt32":1}}}`},
 	{"oneof, not set", marshaler, &pb2.MsgWithOneof{}, `{}`},
 	{"oneof, set", marshaler, &pb2.MsgWithOneof{Union: &pb2.MsgWithOneof_Title{"Grand Poobah"}}, `{"title":"Grand Poobah"}`},
+	{"oneof NullValue", marshaler, &pb2.MsgWithOneof{Union: &pb2.MsgWithOneof_NullValue{stpb.NullValue_NULL_VALUE}}, `{"nullValue":null}`},
 	{"force orig_name", Marshaler{OrigName: true}, &pb2.Simple{OInt32: proto.Int32(4)},
 		`{"o_int32":4}`},
 	{"proto2 extension", marshaler, realNumber, realNumberJSON},
@@ -738,6 +739,7 @@
 	{"oneof orig_name", Unmarshaler{}, `{"Country":"Australia"}`, &pb2.MsgWithOneof{Union: &pb2.MsgWithOneof_Country{"Australia"}}},
 	{"oneof spec name2", Unmarshaler{}, `{"homeAddress":"Australia"}`, &pb2.MsgWithOneof{Union: &pb2.MsgWithOneof_HomeAddress{"Australia"}}},
 	{"oneof orig_name2", Unmarshaler{}, `{"home_address":"Australia"}`, &pb2.MsgWithOneof{Union: &pb2.MsgWithOneof_HomeAddress{"Australia"}}},
+	{"oneof NullValue", Unmarshaler{}, `{"nullValue":null}`, &pb2.MsgWithOneof{Union: &pb2.MsgWithOneof_NullValue{stpb.NullValue_NULL_VALUE}}},
 	{"orig_name input", Unmarshaler{}, `{"o_bool":true}`, &pb2.Simple{OBool: proto.Bool(true)}},
 	{"camelName input", Unmarshaler{}, `{"oBool":true}`, &pb2.Simple{OBool: proto.Bool(true)}},