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Diffstat (limited to 'guides/source/testing.md')
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diff --git a/guides/source/testing.md b/guides/source/testing.md index 2c5b1712cc..d00fcd1f03 100644 --- a/guides/source/testing.md +++ b/guides/source/testing.md @@ -66,18 +66,34 @@ Here's a sample YAML fixture file: ```yaml # lo & behold! I am a YAML comment! david: - name: David Heinemeier Hansson - birthday: 1979-10-15 - profession: Systems development + name: David Heinemeier Hansson + birthday: 1979-10-15 + profession: Systems development steve: - name: Steve Ross Kellock - birthday: 1974-09-27 - profession: guy with keyboard + name: Steve Ross Kellock + birthday: 1974-09-27 + profession: guy with keyboard ``` Each fixture is given a name followed by an indented list of colon-separated key/value pairs. Records are typically separated by a blank space. You can place comments in a fixture file by using the # character in the first column. Keys which resemble YAML keywords such as 'yes' and 'no' are quoted so that the YAML Parser correctly interprets them. +If you are working with [associations](/association_basics.html), you can simply +define a reference node between two different fixtures. Here's an example with +a belongs_to/has_many association: + +```yaml +# In fixtures/categories.yml +about: + name: About + +# In fixtures/articles.yml +one: + title: Welcome to Rails! + body: Hello world! + category: about +``` + #### ERB'in It Up ERB allows you to embed Ruby code within templates. The YAML fixture format is pre-processed with ERB when Rails loads fixtures. This allows you to use Ruby to help you generate some sample data. For example, the following code generates a thousand users: @@ -343,6 +359,17 @@ Notice the 'E' in the output. It denotes a test with error. NOTE: The execution of each test method stops as soon as any error or an assertion failure is encountered, and the test suite continues with the next method. All test methods are executed in alphabetical order. +When a test fails you are presented with the corresponding backtrace. By default +Rails filters that backtrace and will only print lines relevant to your +application. This eliminates the framwork noise and helps to focus on your +code. However there are situations when you want to see the full +backtrace. simply set the `BACKTRACE` environment variable to enable this +behavior: + +```bash +$ BACKTRACE=1 rake test test/models/post_test.rb +``` + ### What to Include in Your Unit Tests Ideally, you would like to include a test for everything which could possibly break. It's a good practice to have at least one test for each of your validations and at least one test for every method in your model. @@ -422,10 +449,12 @@ Now that we have used Rails scaffold generator for our `Post` resource, it has a Let me take you through one such test, `test_should_get_index` from the file `posts_controller_test.rb`. ```ruby -test "should get index" do - get :index - assert_response :success - assert_not_nil assigns(:posts) +class PostsControllerTest < ActionController::TestCase + test "should get index" do + get :index + assert_response :success + assert_not_nil assigns(:posts) + end end ``` @@ -516,7 +545,7 @@ instance variable: ```ruby # setting a HTTP Header -@request.headers["Accepts"] = "text/plain, text/html" +@request.headers["Accept"] = "text/plain, text/html" get :index # simulate the request with custom header # setting a CGI variable @@ -741,42 +770,47 @@ class UserFlowsTest < ActionDispatch::IntegrationTest private - module CustomDsl - def browses_site - get "/products/all" - assert_response :success - assert assigns(:products) + module CustomDsl + def browses_site + get "/products/all" + assert_response :success + assert assigns(:products) + end end - end - def login(user) - open_session do |sess| - sess.extend(CustomDsl) - u = users(user) - sess.https! - sess.post "/login", username: u.username, password: u.password - assert_equal '/welcome', path - sess.https!(false) + def login(user) + open_session do |sess| + sess.extend(CustomDsl) + u = users(user) + sess.https! + sess.post "/login", username: u.username, password: u.password + assert_equal '/welcome', path + sess.https!(false) + end end - end end ``` Rake Tasks for Running your Tests --------------------------------- -You don't need to set up and run your tests by hand on a test-by-test basis. Rails comes with a number of commands to help in testing. The table below lists all commands that come along in the default Rakefile when you initiate a Rails project. +You don't need to set up and run your tests by hand on a test-by-test basis. +Rails comes with a number of commands to help in testing. +The table below lists all commands that come along in the default Rakefile +when you initiate a Rails project. | Tasks | Description | | ----------------------- | ----------- | -| `rake test` | Runs all unit, functional and integration tests. You can also simply run `rake test` as Rails will run all the tests by default| -| `rake test:controllers` | Runs all the controller tests from `test/controllers`| -| `rake test:functionals` | Runs all the functional tests from `test/controllers`, `test/mailers`, and `test/functional`| -| `rake test:helpers` | Runs all the helper tests from `test/helpers`| -| `rake test:integration` | Runs all the integration tests from `test/integration`| -| `rake test:mailers` | Runs all the mailer tests from `test/mailers`| -| `rake test:models` | Runs all the model tests from `test/models`| -| `rake test:units` | Runs all the unit tests from `test/models`, `test/helpers`, and `test/unit`| +| `rake test` | Runs all unit, functional and integration tests. You can also simply run `rake` as Rails will run all the tests by default | +| `rake test:controllers` | Runs all the controller tests from `test/controllers` | +| `rake test:functionals` | Runs all the functional tests from `test/controllers`, `test/mailers`, and `test/functional` | +| `rake test:helpers` | Runs all the helper tests from `test/helpers` | +| `rake test:integration` | Runs all the integration tests from `test/integration` | +| `rake test:mailers` | Runs all the mailer tests from `test/mailers` | +| `rake test:models` | Runs all the model tests from `test/models` | +| `rake test:units` | Runs all the unit tests from `test/models`, `test/helpers`, and `test/unit` | +| `rake test:all` | Runs all tests quickly by merging all types and not resetting db | +| `rake test:all:db` | Runs all tests quickly by merging all types and resetting db | Brief Note About `MiniTest` @@ -871,10 +905,9 @@ class PostsControllerTest < ActionController::TestCase private - def initialize_post - @post = posts(:one) - end - + def initialize_post + @post = posts(:one) + end end ``` @@ -896,7 +929,7 @@ Testing mailer classes requires some specific tools to do a thorough job. ### Keeping the Postman in Check -Your mailer classes — like every other part of your Rails application — should be tested to ensure that it is working as expected. +Your mailer classes - like every other part of your Rails application - should be tested to ensure that it is working as expected. The goals of testing your mailer classes are to ensure that: @@ -990,6 +1023,47 @@ class UserControllerTest < ActionController::TestCase end ``` +Testing helpers +--------------- + +In order to test helpers, all you need to do is check that the output of the +helper method matches what you'd expect. Tests related to the helpers are +located under the `test/helpers` directory. Rails provides a generator which +generates both the helper and the test file: + +```bash +$ rails generate helper User + create app/helpers/user_helper.rb + invoke test_unit + create test/helpers/user_helper_test.rb +``` + +The generated test file contains the following code: + +```ruby +require 'test_helper' + +class UserHelperTest < ActionView::TestCase +end +``` + +A helper is just a simple module where you can define methods which are +available into your views. To test the output of the helper's methods, you just +have to use a mixin like this: + +```ruby +class UserHelperTest < ActionView::TestCase + include UserHelper + + test "should return the user name" do + # ... + end +end +``` + +Moreover, since the test class extends from `ActionView::TestCase`, you have +access to Rails' helper methods such as `link_to` or `pluralize`. + Other Testing Approaches ------------------------ @@ -998,6 +1072,7 @@ The built-in `test/unit` based testing is not the only way to test Rails applica * [NullDB](http://avdi.org/projects/nulldb/), a way to speed up testing by avoiding database use. * [Factory Girl](https://github.com/thoughtbot/factory_girl/tree/master), a replacement for fixtures. * [Machinist](https://github.com/notahat/machinist/tree/master), another replacement for fixtures. +* [Fixture Builder](https://github.com/rdy/fixture_builder), a tool that compiles Ruby factories into fixtures before a test run. * [MiniTest::Spec Rails](https://github.com/metaskills/minitest-spec-rails), use the MiniTest::Spec DSL within your rails tests. * [Shoulda](http://www.thoughtbot.com/projects/shoulda), an extension to `test/unit` with additional helpers, macros, and assertions. * [RSpec](http://relishapp.com/rspec), a behavior-driven development framework |