使用rspec失败的测试（将程序映射出来）会导致错误？

Question

Note: I'm following a tutorial for Ruby on Rails, and thus I'm a complete noob

Basically, in the tutorial I am following, it shows you how to make failed tests that you meet as you go along, like a checklist for your program. My problem is that when I do the test, it sort of outputs what it should, but in errors, which isn't good (I think) because it doesn't match the output of the instructions.

Output: http://pastebin.com/0xyf3aBf (and show below)

Output

Failures:

  1) Static pages Home page should have the content 'Sample App'
     ←[31mFailure/Error:←[0m ←[31mexpect(page).to have_content('Sample App')←[0m

       ←[31mexpected #has_content?("Sample App") to return true, got false←[0m
←[36m     # ./spec/requests/static_pages_spec.rb:9:in `block (3 levels) in <top
(required)>'←[0m

Finished in 0.07 seconds
←[31m1 example, 1 failure←[0m

Failed examples:

←[31mrspec ./spec/requests/static_pages_spec.rb:7←[0m ←[36m# Static pages Home p
age should have the content 'Sample App'←[0m

Randomized with seed 10853   

My static_pages_specs.rb file: http://pastebin.com/L0LHACR4 (and shown below)

static_pages_specs.rb

require 'spec_helper'

describe "Static pages" do

  describe "Home page" do

    it "should have the content 'Sample App'" do
      visit '/static_pages/home'
      expect(page).to have_content('Sample App')
    end
  end
end

Answer 1

Other than the extra control codes (which might just be a symptom from your console or the cut&paste), this looks like a normal test failure. Which you should expect if you have written the test first.

One important part of TDD is indeed to get a simple failing test - with this kind of failure (the have_content matcher has failed to match) - and to then "fix" the failure.

It is also possible to get problems with the test code, which would also need fixing of course. But I don't see anything wrong with your test in this case.

If there was something wrong with the test, you would have to debug it in the more traditional way of applying critical thinking and experience when you read the code. So try to keep the test code simple, and to the point. Break down long complex tests into many short small ones.

Possibly the have_content matcher could be improved to give better context, rather than make a sub-test that you were not aware of . . . that was written by someone else though, and isn't too bad, it still makes some sense (there is presumably no content at all on the target page).