Add time comparison guideline

[pirj]

past?/future?

Noteable offenders:

- if reminder_at < Time.zone.now
+ if reminder_at.past?

- sleep 1 if alarm_at > Time.zone.now
+ sleep 1 if alarm_at.future?

Rails docs:

• future?
• past?

Secondary, informative section:

• before?
• after?

Introduction of before?/after? in Rails 6.0.

before?/after? didn't make to this guideline due to insufficient use, and it would go against our:

A style guide that reflects real-world usage gets used, and a style guide that holds to an ideal that has been rejected by the people it is supposed to help risks not getting used at all - no matter how good it is.

- last_archival_attempt_at + backoff < Time.current
+ last_archival_attempt_at.before? backoff.from_now

[andyw8]

A concern I have is that people are used to < in a SQL query involving dates, and so it feels natural to use it in Rails too.

I agree that before?/after? is a better and more natural API but it might be a step too far to mandate this.

[andyw8]

👍 totally agree with this part.

[pirj]

I'm fine with doing the prime time for past?/future?, and just briefly mentioning before?/after? below the main section with no guidance to use. WDYT?

[andyw8]

Agreed.