Unit tests dynamic finders

Rails
1

Hi all,
I am having a problem with unit tests. Whenever I have a dependency
between two models (B depends on A) deleting A should also delete B.
This is simple with the dependent parameter in the model file of A. But
when I write a test the dependency seems to work, I can’t find the
answer with id 1 anymore(Answer.find(1)). But I appearently do find it
with Answer.find_by_question_id(1) or Answer.find(:first, :conditions =>
“question_id = 1”). What am I doing wrong??
Below you will find the relevant files used in testing.

questions.yml:
first_question:
id: 1
question: “Will fixture files work?”
answer: “No”

answers.yml:
first_answer:
id: 1
question_id: 1

question_test.rb:
class QuestionTest < Test::Unit::TestCase
fixtures :categories, :questions, :answers

def test_destroy
    question = questions(:first)
    id = question.id
    question.destroy
    assert_raise(ActiveRecord::RecordNotFound) {Question.find(1)}
    assert_raise(ActiveRecord::RecordNotFound) {Answer.find(1)}
    assert_raise(ActiveRecord::RecordNotFound)

{Answer.find_by_question_id(1)} <<TROUBLE, ACTUALLY SUCCEEDS
#assert_raise(ActiveRecord::RecordNotFound) {Answer.find(:all,
:conditions => “question_id = 1” )} <<AND AGAIN TROUBLE
end
end

question.rb:
class Question < ActiveRecord::Base
has_one :answer, :dependent => true
end

With many thanks,

Harm