I expect it should work:
```
:) select CAST(CAST('{"x" : 1}', 'Object(\'json\')'), 'Object(Nullable(\'json\'))')

SELECT CAST(CAST('{"x" : 1}', 'Object(\'json\')'), 'Object(Nullable(\'json\'))')

Query id: fb057b45-b72a-4d22-9b38-a3136cdf2465


0 rows in set. Elapsed: 0.002 sec.

Received exception from server (version 22.5.1):
Code: 53. DB::Exception: Received from localhost:9000. DB::Exception: Cast to Object can be performed only from flatten named Tuple, Map or String. Got: Object('json'): While processing CAST(CAST('{"x" : 1}', 'Object(\'json\')'), 'Object(Nullable(\'json\'))'). (TYPE_MISMATCH)
```

@CurtizJ what do you think?
convertFromTime<ToDataType>(vec_to[i],res);
                }
                else
                {
                    if constexpr (to_datetime64)
                    {
                        DateTime64 value = 0;
                        parsed = tryReadDateTime64Text(value, col_to->getScale(), read_buffer, *local_time_zone);
                        vec_to[i] = value;
                    }
                    else if constexpr (IsDataTypeDecimal<ToDataType>)
                        parsed = SerializationDecimal<typename ToDataType::FieldType>::tryReadText(
                            vec_to[i], read_buffer, ToDataType::maxPrecision(), col_to->getScale());
                    else
                        parsed = tryParseImpl<ToDataType>(vec_to[i], read_buffer, local_time_zone);
                }
                if (!isAllRead(read_buffer))
                    parsed = false;
                if (!parsed)
                {
                    if constexpr (std::is_same_v<ToDataType, DataTypeDate32>)
                    {
                        vec_to[i] = -static_cast<Int32>(DateLUT::instance().getDayNumOffsetEpoch());
                    }
                    else
                    {
                        vec_to[i] = static_cast<typename ToDataType::FieldType>(0);
                    }
                }
                if constexpr (exception_mode == ConvertFromStringExceptionMode::Null)