Nil.errors and error_messages_for

Rails
1

Hi there

I’m wanting to re-render my index action in the event of an object not
getting saved; I use render not redirect so as to preserve the
validation errors.

I’m using the error_messages_for helper in my view but I get a
nil.errors error when I attempt to display the view.

I can avoid this error by setting up @discount = Discount.new in my
index action, but this obliterates the instance variable with the
attached error messages.

I’m chasing my tail on this and any clues would be appreciated.

2

bongoman wrote:

I’m chasing my tail on this and any clues would be appreciated.

Hear galloping think horses not zebras, here…

Your action goes like…

@discount = Discount.new(params[:discount]) # warning use
attr_protected!
unless @discount.save
render :action => ‘index’
end

So… uh… @discount indeed contains a stuffed Discount instance with
populated
errors… so what’s the problem??

So post your actual action instead of making us guess? (-8

3

So… uh… @discount indeed contains a stuffed Discount instance
with populated
errors… so what’s the problem??

Well it only does when the index template is rendered AFTER validation
fails. The same action gets invoked prior to the form submission at
which point in time there is no @discount variable, hence the
nil.errors

So post your actual action instead of making us guess? (-8

Here we go:

@discount = Discount.find(params[:id])
if @discount.update_attributes(params[:discount])
  flash[:notice_good] = "Discounts have been updated"
  redirect_to :action=> 'index'
else
  index # I need to do this in order to get my instance variables

populated for the index view
render :action => ‘index’
end

4

Here we go:

@discount = Discount.find(params[:id])
if @discount.update_attributes(params[:discount])
  flash[:notice_good] = "Discounts have been updated"
  redirect_to :action=> 'index'
else
  index # I need to do this in order to get my instance variables

populated for the index view

and … index re-populates @discount?

put this inside the index:

@discount ||= Discount.new