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| -rw-r--r-- | guides/source/testing.md | 95 |
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diff --git a/guides/source/testing.md b/guides/source/testing.md index 89add0d10f..655827145c 100644 --- a/guides/source/testing.md +++ b/guides/source/testing.md @@ -530,7 +530,7 @@ NOTE: Functional tests do not verify whether the specified request type is accep ### The Four Hashes of the Apocalypse -After a request has been made using one of the 6 methods (`get`, `post`, etc.) and processed, you will have 4 Hash objects ready for use: +After a request has been made and processed, you will have 4 Hash objects ready for use: * `assigns` - Any objects that are stored as instance variables in actions for use in views. * `cookies` - Any cookies that are set. @@ -553,8 +553,8 @@ assigns["something"] assigns(:something) You also have access to three instance variables in your functional tests: * `@controller` - The controller processing the request -* `@request` - The request -* `@response` - The response +* `@request` - The request object +* `@response` - The response object ### Setting Headers and CGI variables @@ -575,6 +575,10 @@ post :create # simulate the request with custom env variable ### Testing Templates and Layouts +Eventually, you may want to test whether a specific layout is rendered in the view of a response. + +#### Asserting Templates + If you want to make sure that the response rendered the correct template and layout, you can use the `assert_template` method: @@ -583,24 +587,22 @@ test "index should render correct template and layout" do get :index assert_template :index assert_template layout: "layouts/application" + + # You can also pass a regular expression. + assert_template layout: /layouts\/application/ end ``` -Note that you cannot test for template and layout at the same time, with one call to `assert_template` method. -Also, for the `layout` test, you can give a regular expression instead of a string, but using the string, makes -things clearer. On the other hand, you have to include the "layouts" directory name even if you save your layout -file in this standard layout directory. Hence, +NOTE: You cannot test for template and layout at the same time, with a single call to `assert_template`. -```ruby -assert_template layout: "application" -``` +WARNING: You must include the "layouts" directory name even if you save your layout file in this standard layout directory. Hence, `assert_template layout: "application"` will not work. -will not work. +#### Asserting Partials -If your view renders any partial, when asserting for the layout, you have to assert for the partial at the same time. +If your view renders any partial, when asserting for the layout, you can to assert for the partial at the same time. Otherwise, assertion will fail. -Hence: +Remember, we added the "_form" partial to our creating Articles view? Let's write an assertion for that in the `:new` action now: ```ruby test "new should render correct layout" do @@ -609,22 +611,81 @@ test "new should render correct layout" do end ``` -is the correct way to assert for the layout when the view renders a partial with name `_form`. Omitting the `:partial` key in your `assert_template` call will complain. +This is the correct way to assert for when the view renders a partial with a given name. As identified by the `:partial` key passed to the `assert_template` call. -### A Fuller Functional Test Example +### Testing `flash` notices -Here's another example that uses `flash`, `assert_redirected_to`, and `assert_difference`: +If you remember from earlier one of the Four Hashes of the Apocalypse was `flash`. + +We want to add a `flash` message to our blog application whenever someone +successfully creates a new Article. + +Let's start by adding this assertion to our `test_should_create_article` test: ```ruby test "should create article" do assert_difference('Article.count') do - post :create, article: {title: 'Hi', body: 'This is my first article.'} + post :create, article: {title: 'Some title'} end + assert_redirected_to article_path(assigns(:article)) assert_equal 'Article was successfully created.', flash[:notice] end ``` +If we run our test now, we should see a failure: + +```bash +$ bin/rake test test/controllers/articles_controller_test.rb test_should_create_article +Run options: -n test_should_create_article --seed 32266 + +# Running: + +F + +Finished in 0.114870s, 8.7055 runs/s, 34.8220 assertions/s. + + 1) Failure: +ArticlesControllerTest#test_should_create_article [/Users/zzak/code/bench/sharedapp/test/controllers/articles_controller_test.rb:16]: +--- expected ++++ actual +@@ -1 +1 @@ +-"Article was successfully created." ++nil + +1 runs, 4 assertions, 1 failures, 0 errors, 0 skips +``` + +Let's implement the flash message now in our controller. Our `:create` action should now look like this: + +```ruby +def create + @article = Article.new(article_params) + + if @article.save + flash[:notice] = 'Article was successfully created.' + redirect_to @article + else + render 'new' + end +end +``` + +Now if we run our tests, we should see it pass: + +```bash +$ bin/rake test test/controllers/articles_controller_test.rb test_should_create_article +Run options: -n test_should_create_article --seed 18981 + +# Running: + +. + +Finished in 0.081972s, 12.1993 runs/s, 48.7972 assertions/s. + +1 runs, 4 assertions, 0 failures, 0 errors, 0 skips +``` + ### Testing Views Testing the response to your request by asserting the presence of key HTML elements and their content is a useful way to test the views of your application. The `assert_select` assertion allows you to do this by using a simple yet powerful syntax. |