Test fail with ActionView::Template::Error: undefined method `name' for nil:NilClass

问题

I have on view show.html.erb

 <%= @question.user.lesson_id %>

and this is on browser a number.

my questions_controller.rb is

 def show
    @question = Question.find(params[:id])
    @comments = @question.comments.all
    if user_signed_in?
            @rating_currentuser = @question.ratings.find_by_user_id(current_user.id)
            unless @rating_currentuser
            @rating_currentuser = current_user.ratings.new
   end
 end

and my questions_controller_test.rb

   test "should show question signed in" do
    sign_in users(:user2)
    get :show, :id => @question_user1.to_param
    assert_response :success
   end

and everything is ok (browser and testing)

when change view show.html.erb

   <%= @question.user.lesson.name %>

I am OK with browser but fail testing with

   ActionView::Template::Error: undefined method `name' for nil:NilClass.

I try this

  @name = Lesson.find(params[:id])

on questions_controller.rb then test fail with

  Expected response to be a <:success>, but was <302>

回答1:

Using try can potentially mask the underlying problem.

For example, when I had this error it was because I wasn't creating a model object without the correct foreign key references fixed up - the view was rendering using the FK association with the name attribute - e.g. Product.ProductType.name. If I had used try to workaround it, it would have masked this fault in my test which would have been undesirable in the test. Once I had added the correct references everything worked as it should have with no need for try(:name).

回答2:

The solution from this answer

is use the try method and change view as

<%= @question.user.lesson.try(:name) %>

来源：https://stackoverflow.com/questions/10840783/test-fail-with-actionviewtemplateerror-undefined-method-name-for-nilnilc

标签

ruby-on-rails

testing

null