where do I report this DateTime bug?

rubyonrails-talk
1

I have isolated what appears to be a bug in the Rails extensions to DateTime, but I don't know where to report it.

I have a standalone file to demonstrate the bug, but the punch line is that this code:

    TestRecord.create!(:f_datetime => (expected = DateTime.jd(2000000)))     found = TestRecord.first.f_datetime

    puts("expected == found => #{expected == found}")     puts("expected = #{expected.to_formatted_s(:rfc822)}")     puts("found = #{found.to_formatted_s(:rfc822)}")

generates this response:

    expected == found => true     expected = Wed, 14 Sep 0763 00:00:00 +0000     found = Sat, 14 Sep 0763 00:00:00 +0000

So. The dates are equal, but was that day a Wednesday or a Saturday?

2

Can you post the contents of schema.rb section for the table. Also it would be interesting to put in some inspect debug for expected and found.

Colin

3

Can you post the contents of schema.rb section for the table. Also it would be interesting to put in some inspect debug for expected and found.

Colin:

Done. See Demonstration of bug in DateTime#to_formatted_s(:rfc822) · GitHub for code and results.

As for "inspect debug for expected and found", I assume you mean like this:

    puts("expected = #{expected.to_formatted_s(:rfc822)} (#{expected.inspect})")     puts("found = #{found.to_formatted_s(:rfc822)} (#{found.inspect})")

=>

expected = Wed, 14 Sep 0763 00:00:00 +0000 (Wed, 14 Sep 0763 00:00:00 +0000) found = Sat, 14 Sep 0763 00:00:00 +0000 (Sat, 14 Sep 0763 00:00:00 UTC +00:00)

HTH.

- ff

4

I've created:

  https://github.com/rails/rails/issues/6814

... which seems like the correct place to report this. I'm sure I'll hear from the rails admin team soon enough if that's not the right place.

- ff

5

Can you post the contents of schema.rb section for the table. Also it would be interesting to put in some inspect debug for expected and found.

Colin:

Done. See Demonstration of bug in DateTime#to_formatted_s(:rfc822) · GitHub for code and results.

As for "inspect debug for expected and found", I assume you mean like this:

puts("expected = #{expected.to_formatted_s(:rfc822)} (#{expected.inspect})") puts("found = #{found.to_formatted_s(:rfc822)} (#{found.inspect})")

What is the class of found?

Colin

6

Also I don't think you have told us which versions of ruby and rails you are using.

Colin

7

Colin Law wrote in post #1065800:

What is the class of found?

I updated the above mentioned gist. 'expected' is a DateTme, 'found' is ActiveSupport::TimeWithZone.

Also I don't think you have told us which versions of ruby and rails you are using.

Apologies, this was buried at the end of the OP:

PS: I'm using postgresql with Ruby 1.93 and Rails 3.2.1

But this is all now moot: I posted this as a Rails issue:

   two DateTime objects are == but print differently · Issue #6814 · rails/rails · GitHub

where @pixeltrix patiently educated me on the anomalies of ancient calendar systems. The best line was "[calendar reforms] can lead to oddities like William Shakespeare and Miguel de Cervantes dying on the same date but 10 days apart." He also suggests using #gregorian to adjust the datetime before converting to time, e.g:

    >> DateTime.jd(2000000).gregorian     => Wed, 18 Sep 0763 00:00:00 +0000

So: not a bug. Just a reality of calendar reforms.