Invalid timezone offsets while parsing dates in old messages.

[dwsteele]

I have a bunch of rather old messages that I am running through the parser and some of them are giving strange results.

For example, Date: Thu, 10 Jul 1997 14:53:31 EST5EDT' parses as DateTime { year: 1997, month: 7, day: 10, hour: 14, minute: 53, second: 31, tz_before_gmt: false, tz_hour: 50, tz_minute: 0 }`. An offset of 50 hours is pretty clearly off.

Another example: Date: Sun, 27 Oct 2002 23:57:07 EST yields { year: 2002, month: 10, day: 27, hour: 23, minute: 57, second: 7, tz_before_gmt: false, tz_hour: 0, tz_minute: 0 }. In this case the offset is 0 -- less weird bit still incorrect.

Any chance these are correctable? Unfortunately I have a fair number of messages with this issue. For now I have written some code to detect unparsable timezones and thrown an error. Maybe the crate could at least throw an error if it cannot parse the timezone?

[mdecimus]

This library never returns errors unless the message is completely unparseable. For everything else it makes a best effort to extract as much information as possible from non-conformant messages. As the README explains:

In general, this library abides by the Postel's law or Robustness Principle which states that an implementation must be conservative in its sending behavior and liberal in its receiving behavior. This means that mail-parser will make a best effort to parse non-conformant e-mail messages as long as these do not deviate too much from the standard.

[dwsteele]

For everything else it makes a best effort to extract as much information as possible from non-conformant messages

OK, fair enough, but 50 is not even a valid timezone offset. If the offset was kept within valid bounds it would make the parsed time at least more accurate. Also, Thunderbird is able to correctly parse these timezones so it seems possible to do so.

[mdecimus]

I will keep the issue open and will look into it as soon as I have a chance. Thanks.