parseWithNamedTz function
Parse a DateTime string with a named TZ like PDT
Dart do not support parsing of Z on DateFormat and always will default to UTC this is a hacky way to move the date offset manually. this will not use DST or any other external information, just the offset
reference: https://github.com/dart-lang/intl/issues/19
Implementation
DateTime parseWithNamedTz(String value, ParseInfo pi) {
final dateStr = (pi.fcb != null) ? pi.fcb!(value, pi) : value;
try {
final tmp = DateFormat(pi.format).parseUtc(dateStr);
final matchStr = pi.rgx.matchAsPrefix(dateStr);
if (matchStr != null) {
final tzName = matchStr.group(2);
final data = tzInfoDb[tzName];
if (data != null) {
final duration = Duration(minutes: data.offset.abs());
return (data.offset < 0) ? tmp.add(duration) : tmp.subtract(duration);
}
}
return tmp;
} on FormatException {
throw FormatException('(parseWithNamedTz) format error: [$dateStr] with [${pi.format}]');
}
}