validates_presence_of Date with '00' year fails

rubyonrails-talk
1

Hi there

I've come across an interesting scenario with validates_presence_of and Dates in Rails. I've been looking through the Rails code but I just can't figure out where in Rails the date parsing which presumably causes this issue is happening.

The problem is this. If you try and create a model using a date string in the format "dd MMM yy" but you specify a year of '00', 'validates_presence_of' fails because the Date object Rails converts the String to is nil. If you specify any other 2-digit year it's fine. Here's a simple example test case:

class Model   validates_presence_of :dated_on end

# this works m = Model.create(:dated_on => '20 Apr 01') assert m.errors.empty?

# this fails m = Model.create(:dated_on => '20 Apr 00') assert m.errors.empty?

Has anyone come across this before and/or would anyone be able to point me to where in the Rails code base the date is parsed so I can look at implementing a workaround? I just can't spot it!

Many thanks Olly

2

Ultimately, the parsing of a date comes down to the new_date method in activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb. It’s currently on line 166 of that file in edge Rails. That method returns nil if the year is 0. I don’t know why it works that way, but at least you now know why you see the behavior that you do.

Regards, Craig