confidence_check - Get confidence in your test setup

[](https://app.circleci.com/pipelines/github/sustainable-rails/confidence-check)

Sometimes tests have some setup required before you run the test, and sometimes that setup is complicated, and sometimes that setup can break if other parts of the system aren’t working. When that happens, you can a test failure that doesn’t mean your code is broken, just that some other code is broken.

```ruby visit “/” click_on “sign_up”

fill_in :username, with: “davetron5000” expect { click_on “Create an Account” }.to change { Account.count }.by(1) ```

What if the sign_up link is broken, but your account registration code is working perfectly? You’ll get a test failure on that call to fill_in. This is confusing.

```ruby confidence_check do visit “/” click_on “sign_up” end

fill_in :username, with: “davetron5000” expect { click_on “Create an Account” }.to change { Account.count }.by(1) ```

Now, if something goes wrong getting to the page, i.e. setting up for your test, you’ll get a different error: CONFIDENCE CHECK FAILED.

This can help tremendously with isolating the root cause of a test failure. Instead of digging into the code you are testing, you can quickly see that some other code that is needed just to run a test is broken.

Install

> gem install confidence-check

Or, if using a Gemfile:

ruby gem "confidence-check"

Setup - RSpec

1. Include ConfidenceCheck::ForRSpec in your test. The most common way is in your spec_helper.rb:

   ruby RSpec.configure do |c| c.include ConfidenceCheck::ForRSpec end

2. You can now call confidence_check anywhere you need to assert your test is set up:

   ```ruby RSpec.describe Person do include ConfidenceCheck describe “#age” do it “is based on birthdate” do person = create(:person)

     confidence_check do
       expect(person.birthdate).not_to be_nil
     end
   
     expect(person.age).to eq(47)
   end   end end ```
   

Setup - Minitest

1. Include ConfidenceCheck::ForMinitest in your test. For Rails, you’d include this in ActiveSupport::TestCase:

   ```ruby # test/test_helper.rb

   class ActiveSupport::TestCase include ConfidenceCheck::ForMinitest

   # … end ```

2. You can now call confidence_check anywhere you need to assert your test is set up:

   ```ruby class PersonTest < MiniTest::Test include ConfidenceCheck def test_age person = create(:person)

   confidence_check do
     refute_nil person.birthdate
   end
   
   assert_equal 47,person.age   end end ```
   

Setup - Custom

1. The module ConfidenceCheck::CheckMethod makes a call to exception_klasses, which returns an array of exception classes you want to rescue inside a confidence_check call. You’ll need to implement this yourself:

   ruby module MyCustomConfidenceCheck include ConfidenceCheck::CheckMethod def exception_klasses [ MyCustomError ] end end

2. Note that you can include any of the other modules as a base. For example, if you want to use RSpec but add your own additional method: ruby module MyCustomConfidenceCheck include ConfidenceCheck::ForRSpec include ConfidenceCheck::CheckMethod def exception_klasses super + [ MyCustomError ] end end
3. Now, you need to include this module in your tests. HOw to do this dependson how you are writing tests, but hopefully it’s as simple as include MyCustomConfidenceCheck

Setup - with Capybara

Capybara raises several exceptions if navigation or page manipulation fails. These are almost always the types of failures a confidence check should notify you about because they usually mean a page or pages aren’t even working enough for you to execute a test.

If you use the *WithCapybara versions of the modules, you can wrap your Capybara navigation commands in a confidence_check:

RSpec

ruby RSpec.configure do |c| c.include ConfidenceCheck::ForRSpec::WithCapybara end

Minitest

```ruby # test/test_helper.rb

class ActiveSupport::TestCase include ConfidenceCheck::ForMinitest::WithCapybara

# … end ```

Custom

```ruby module MyCustomConfidenceCheck include ConfidenceCheck::CheckMethod def exception_klasses [ MyCustomError, Capybara::CapybaraError ] end end

OR, to e.g. re-use RSpec’s

module MyCustomConfidenceCheck include ConfidenceCheck::ForRSpec::WithCapybara include ConfidenceCheck::CheckMethod def exception_klasses super + [ MyCustomError ] end end ```

Developing

• Set up with bin/setup
• Run tests with bin/rspec or bin/rake