class ActiveSupport::TimeZone

def parse(str, now = now())

If the string is invalid then an +ArgumentError+ could be raised.

Time.zone.parse('Mar 2000') # => Wed, 01 Mar 2000 00:00:00 HST -10:00

components are supplied, then the day of the month defaults to 1:
However, if the date component is not provided, but any other upper

Time.zone.parse('22:30:00') # => Fri, 31 Dec 1999 22:30:00 HST -10:00
Time.zone.now # => Fri, 31 Dec 1999 14:00:00 HST -10:00

TimeZone#now:
If upper components are missing from the string, they are supplied from

Time.zone.parse('1999-12-31 14:00:00') # => Fri, 31 Dec 1999 14:00:00 HST -10:00
Time.zone = 'Hawaii' # => "Hawaii"

of +self+ from parsed string.
Method for creating new ActiveSupport::TimeWithZone instance in time zone 
def parse(str, now = now())
  parts_to_time(Date._parse(str, false), now)
end