fails:Time#zone returns the time zone used for time
fails:Time#zone returns nil for a Time with a fixed offset
fails:Time#zone returns the correct timezone for a local time
fails:Time#zone returns nil when getting the local time with a fixed offset
fails:Time#zone returns UTC when called on a UTC time
fails:Time#zone Encoding.default_internal is set returns the string with the default internal encoding
fails:Time#zone Encoding.default_internal is set doesn't raise errors for a Time with a fixed offset
