I have an
age method on my
Waiver model that looks like:
def age(date = nil) if date.nil? date = Date.today end age = 0 unless date_of_birth.nil? age = date.year - date_of_birth.year age -= 1 if date < date_of_birth + age.years #for days before birthday end return age end
I then have a spec that looks like:
it "calculates the proper age" do waiver = FactoryGirl.create(:waiver, date_of_birth: 12.years.ago) waiver.age.should == 12 end
When I run this spec I get
comparison of Date with ActiveSupport::TimeWithZone failed. What am I doing wrong?
Failures: 1) Waiver calculates the proper age Failure/Error: waiver.age.should == 12 ArgumentError: comparison of Date with ActiveSupport::TimeWithZone failed # ./app/models/waiver.rb:132:in `<' # ./app/models/waiver.rb:132:in `age' # ./spec/models/waiver_spec.rb:23:in `block (2 levels) in <top (required)>'
You are comparing an instance of
Date with an instance of
ActiveSupport::TimeWithZone in the expression
date < date_of_birth + age.years; ActiveSupport::TimeWithZone is, according to the docs, a Time-like class that can represent a time in any time zone. You simply can’t compare
Time objects without performing some kind of conversion. Try
Date.today < Time.now on a console; you’ll see a similar error.
12.years.ago and typical ActiveRecord timestamps are instances of ActiveSupport::TimeWithZone. You are best off ensuring that you deal only with
Time objects or
Date objects, but not both in this method. To make your comparison date-to-date, the expression could instead be written as:
age -= 1 if date < (date_of_birth + age.years).to_date