Please help me make this Rails code more dry. I must be missing something very obvious

Question

This rails validation code is so ugly, and there must be a better way to do it.

The short story is my user is inputting data from test results. Each specific test has 4 measurements. Usually the user inputs all 5 tests (20 measurements), but it's not always required. I just need to check that if a tester started inputting data for a test, he input all 4 measurements in that test.

(Later I will make a validation class, but I'm using this to get started)

Edit: To clarify, the 'tests' are measurements on materials (unrelated to software). the testers record the data on paper, and later it is input into this application

<pre>
def must_input_full_test

  #test Top Section
  if top_section_1 || top_section_2 || top_section_3 || top_section_4
    found_at_least_one = true
    #at least one is present; now check if any are empty
    if top_section_1.nil?
      errors.add :top_section_1, "Must fill in four values for a test"
    end
    if top_section_2.nil?
      errors.add :top_section_2, "Must fill in four values for a test"
    end
    if top_section_3.nil?
      errors.add :top_section_3, "Must fill in four values for a test"
    end
    if top_section_4.nil?
      errors.add :top_section_4, "Must fill in four values for a test"
    end
  end

  #test Bottom Section
  if bottom_section_1 || bottom_section_2 || bottom_section_3 || bottom_section_4
    found_at_least_one = true
    #at least one is present; now check if any are empty
    if bottom_section_1.nil?
      errors.add :bottom_section_1, "Must fill in four values for a test"
    end
    if bottom_section_2.nil?
      errors.add :bottom_section_2, "Must fill in four values for a test"
    end
    if bottom_section_3.nil?
      errors.add :bottom_section_3, "Must fill in four values for a test"
    end
    if bottom_section_4.nil?
      errors.add :bottom_section_4, "Must fill in four values for a test"
    end
  end

  #test Bottom
  if bottom_1 || bottom_2 || bottom_3 || bottom_4
    found_at_least_one = true
    #at least one is present; now check if any are empty
    if bottom_1.nil?
      errors.add :bottom_1, "Must fill in four values for a test"
    end
    if bottom_2.nil?
      errors.add :bottom_2, "Must fill in four values for a test"
    end
    if bottom_3.nil?
      errors.add :bottom_3, "Must fill in four values for a test"
    end
    if bottom_4.nil?
      errors.add :bottom_4, "Must fill in four values for a test"
    end
  end

  #test Middle Section
  if middle_1 || middle_2 || middle_3 || middle_4
    found_at_least_one = true
    #at least one is present; now check if any are empty
    if middle_1.nil?
      errors.add :middle_1, "Must fill in four values for a test"
    end
    if middle_2.nil?
      errors.add :middle_2, "Must fill in four values for a test"
    end
    if middle_3.nil?
      errors.add :middle_3, "Must fill in four values for a test"
    end
    if middle_4.nil?
      errors.add :middle_4, "Must fill in four values for a test"
    end
  end

  #test Top
  if top_1 || top_2 || top_3 || top_4
    found_at_least_one = true
    #at least one is present; now check if any are empty
    if top_1.nil?
      errors.add :top_1, "Must fill in four values for a test"
    end
    if top_2.nil?
      errors.add :top_2, "Must fill in four values for a test"
    end
    if top_3.nil?
      errors.add :top_3, "Must fill in four values for a test"
    end
    if top_4.nil?
      errors.add :top_4, "Must fill in four values for a test"
    end
  end

  if !found_at_least_one
    errors.add :middle_1, "Must fill in at least some test data"
  end
end
<code>

Answer 1

Can you change the code you're testing? It would be best to have something like this (in JSON):

{
  'top' : [section1, section2, section3, section4],
  'middle' : [section1, section2, section3, section4],
  'bottom' : [section1, section2, section3, section4]
}

So you'll have a hash with the keys :top, :middle and :bottom (or whatever you need) and each value of that hash will be an array with four values, which correspond to the _1, _2, _3, _4 you've got at the moment.

With a structure like that, you can easily iterate over it.

---

Edit: As you can't change your model, you'll need to bend your tests to fit. Using the technique I outlined, you can create strings that correspond to your different model attributes, then use read_attribute(attr_string) to get the attribute value. If you're having problems doing that, I think you'll need to ask a new question.