Testing time zones

Since almost all applications report time in some way, nearly all applications will need to handle different time zones. Even if your customers are clustered in a long thin stripe along the Greenwich Meridian, daylight savings time and leap seconds can still cause issues. Here are the considerations when adding them to your test plan.

Let’s examine the case of creating a conference since that demonstrates all the issues you are likely to come across. In that case, there are six time zones to consider:

• The initial time zone of the conference creator
• The initial time zone of the conference invitee
• The conference creator moving to a different time zone
• The conference invitee moving to a different time zone
• The initial time zone of the conference
• The updated time zone of the conference

In each case, you need to ensure that people seeing the conference both from within the time zone and outside it can see the conference reported...