Datetime_select, is creating an instance of the Time class

Rails
1

Hello

It seems that datetime_select, is creating an instance of the Time
class. Why would that be?

I found this while building a site where people can create vigils
(prayer vigils, peace vigils, etc). When I added a validation method
that compared start_date to created_at, it generated the error:

ArgumentError (comparison of Time with DateTime failed):

I was able to put a breakpoint in the create action of my vigil
controller and found that @vigil.start_date.class returns Time type.

I’m running Rails 1.2.3 on Ruby version 1.84.20 on a Windows XP box.

The relevant code is:

View:
<%= datetime_select ‘vigil’, ‘start_date’ %>

Vigil Controller:

def new
s = DateTime.now
e = s.succ
@vigil = Vigil.new(:start_date => s, :end_date => e)
end

def create
@vigil = Vigil.new(params[:vigil])

@vigil.start_date.class returns Time

end

Model
class Vigil < ActiveRecord::Base
def validate
if start_date < created_at
errors.add(:start_date, “must be in the future”)
end
end
end

Migration for vigil table:

class CreateVigils < ActiveRecord::Migration
def self.up
create_table :vigils do |t|
t.column :name, :string, :null => false
t.column :purpose, :string, :null => false
t.column :location, :string
t.column :start_date, :datetime, :null => false
t.column :end_date, :datetime, :null => false
t.column :owner_id, :integer
t.column :recipient, :string
t.column :created_at, :datetime
t.column :updated_at, :datetime
t.column :lock_version, :integer, :default => 0
end
end

def self.down
drop_table :vigils
end
end

Your help is appreciated!

Dave

2

Can anyone verify this for me?

Thanks,
Dave

3

Hey Dave,
The time classes in Ruby are a bit confusing.

Pretty much everywhere “Time” gets used, instead of “DateTime”, and it
works very well.

Time behaves exactly as you would expect DateTime to.
In particular any database column defined to be “datetime” will return
an object of the type “Time”.

So, in conclusion.

def new
s = Time.now
e = s.succ
end

def create
@vigil = Vigil.new(params[:vigil])
success = @vigil.save
end

you probably also want to compare start_date with Time.now, it seems

more relevant than “created_at”

Model
class Vigil < ActiveRecord::Base
def validate
if start_date < Time.now
errors.add(:start_date, “must be in the future”)
end
end
end

Dave Dumaresq wrote:

Can anyone verify this for me?

Thanks,
Dave