def _validate_test_data_for_zone(
self,
zone_name: str,
items: List[TestItem],
) -> int:
"""Compare the given test 'items' generatd by TestDataGenerator (using
pytz) with the expected datetime components from ZoneSpecifier. Returns
the number of errors.
"""
zone_info = self.zone_infos[zone_name]
zone_specifier = ZoneSpecifier(
zone_info_data=zone_info,
viewing_months=self.viewing_months,
debug=self.debug_specifier,
in_place_transitions=self.in_place_transitions,
optimize_candidates=self.optimize_candidates)
num_errors = 0
for item in items:
if self.year is not None and self.year != item.y:
continue
# Print out diagnostics if mismatch detected or if debug flag given
unix_seconds = item.epoch + SECONDS_SINCE_UNIX_EPOCH
ldt = datetime.utcfromtimestamp(unix_seconds)
header = (f'======== Testing {zone_name}; '
f'at {_test_item_to_string(item)}w; '
f'utc {ldt}; '
f'epoch {item.epoch}; '
f'unix {unix_seconds}')
if self.debug_specifier:
logging.info(header)
info = zone_specifier.get_timezone_info_for_seconds(item.epoch)
if not info:
logging.info("timezone info not found")
continue
is_matched = info.total_offset == item.total_offset
status = '**Matched**' if is_matched else '**Mismatched**'
ace_time_string = to_utc_string(info.utc_offset, info.dst_offset)
utc_string = to_utc_string(item.total_offset - item.dst_offset,
item.dst_offset)
body = (f'{status}: '
f'AceTime({ace_time_string}); '
f'Expected({utc_string})')
if is_matched:
if self.debug_specifier:
logging.info(body)
zone_specifier.print_matches_and_transitions()
else:
num_errors += 1
if not self.debug_specifier:
logging.error(header)
logging.error(body)
zone_specifier.print_matches_and_transitions()
return num_errors
class acetz(tzinfo):
"""An implementation of datetime.tzinfo using the ZoneSpecifier class
from AceTime/tools.
"""
def __init__(self, zone_info: ZoneInfo):
self.zone_info = zone_info
self.zs = ZoneSpecifier(zone_info, use_python_transition=True)
def utcoffset(self, dt: Optional[datetime]) -> timedelta:
assert dt
info = self.zs.get_timezone_info_for_datetime(dt)
if not info:
raise Exception(f'Unknown timezone info for '
f'{dt.year:04}-{dt.month:02}-{dt.day:02} '
f'{dt.hour:02}:{dt.minute:02}:{dt.second:02}')
return timedelta(seconds=info.total_offset)
def dst(self, dt: Optional[datetime]) -> timedelta:
assert dt
offset_info = self.zs.get_timezone_info_for_datetime(dt)
if not offset_info:
raise Exception(f'Unknown timezone info for '
f'{dt.year:04}-{dt.month:02}-{dt.day:02} '
f'{dt.hour:02}:{dt.minute:02}:{dt.second:02}')
return timedelta(seconds=offset_info.dst_offset)
def tzname(self, dt: Optional[datetime]) -> str:
assert dt
offset_info = self.zs.get_timezone_info_for_datetime(dt)
if not offset_info:
raise Exception(f'Unknown timezone info for '
f'{dt.year:04}-{dt.month:02}-{dt.day:02} '
f'{dt.hour:02}:{dt.minute:02}:{dt.second:02}')
return offset_info.abbrev
def fromutc(self, dt: Optional[datetime]) -> datetime:
"""Override the default implementation in tzinfo which does not make
sense for acetz.
The 'dt' passed into this function from datetime.astimezone() is a weird
one: the components are in UTC time, but the timezone is the target
tzinfo, in other words, the same acetz as self.
Warning: Do NOT call dt.isoformat() from this method, because it causes
an infinite recursion as it tries to figure out the UTC offset. Use
{dt.date()} and {dt.time()} instead.
"""
if not isinstance(dt, datetime):
raise TypeError("fromutc() requires a datetime argument")
if dt.tzinfo is not self:
raise ValueError("dt.tzinfo is not self")
# Extract the epoch_seconds of the source 'dt'
assert dt is not None
utcdt = dt.replace(tzinfo=timezone.utc)
unix_seconds = int(utcdt.timestamp())
epoch_seconds = unix_seconds - SECONDS_SINCE_UNIX_EPOCH
# Search the transitions for the matching Transition
offset_info = self.zs.get_timezone_info_for_seconds(epoch_seconds)
if not offset_info:
raise ValueError(f"transition not found for {epoch_seconds}")
# Convert the date/time fields into local date/time and attach
# the current acetz object.
newutcdt = utcdt + timedelta(seconds=offset_info.total_offset)
newdt = newutcdt.replace(tzinfo=self, fold=offset_info.fold)
return newdt
def zone_specifier(self) -> ZoneSpecifier:
return self.zs
