Time#to_date returning incorrect dates for pre-Gregorian calendars

[nightsurge]

On 52-stable, Time.parse('0001-01-01').to_date Is returning Jan 3, 0001, instead of Jan 1, 0001.
In our app there are RPG/DB2 legacy tables that store 0001-01-01 as a default date. We are trying to check for that default value and it is now failing because of this bug. It appears when this string is parsed as a Date when creating the Ruby/ActiveRecord object, it must be using Time#to_date at some point, yes?

In versions prior to 50-stable, this worked correctly for us. I see that from 50-stable and newer, the Gregorian Calendar was implemented, but there should be a fallback written into the code to handle dates that exist prior to Gregorian dates 1582. Is there a config somewhere to ignore this, or an easy way for me to monkeypatch this option into 52-stable (the highest version or DB2 database connection can support).

[nightsurge]

I was able to get around this by updating the RubyJdbcConnection.java class's dateToRuby method:

protected IRubyObject dateToRuby(final ThreadContext context,
        final Ruby runtime, final ResultSet resultSet, final int column)
        throws SQLException {

        final Date value = resultSet.getDate(column);
        if ( value == null ) {
            // FIXME: Do we really need this wasNull check here?
            return resultSet.wasNull() ? context.nil : RubyString.newEmptyString(runtime);
        }

        if ( rawDateTime != null && rawDateTime.booleanValue() ) {
            return RubyString.newString(runtime, DateTimeUtils.dateToString(value));
        }

        return DateTimeUtils.newDateAsTime(context, value, DateTimeZone.UTC).callMethod(context, "to_datetime").callMethod(context, "to_date");
    }

Specifically, added a "to_datetime" intermediary method which fixes the calendar issue.