This recipe requires that you have already completed the Reacting to URL parameters recipe, as it relies on SearchFromURLController being present in your Salesforce instance.

The tests successfully execute as shown in the following screenshot:

Navigating back to the Apex Classes setup page by clicking on Your Name | Setup | Develop | Apex Classes shows that the tests have achieved 100 percent coverage of the controller.

The test class contains two unit test methods. The first method tests that the search is correctly executed when the search term is passed on the page URL. As unit tests do not have access to organization data, the first task for the test is to set up three test accounts.

List<Account> accs=new List<Account>();
accs.add(new Account(Name='Unit Test'));
accs.add(new Account(Name='Unit Test 2'));
accs.add(new Account(Name='The Test Account'));
insert accs;

As the controller is reacting to parameters on the URL, the page reference must be set up and populated with the name parameter.

PageReference pr=Page.SearchFromURL;
pr.getParameters().put('name', 'Unit');
Test.setCurrentPage(pr);

Finally, the controller is instantiated, which causes the action method that executes the search to be invoked from the constructor. The test method then confirms that the search was executed and the actual number of matches equals the expected number.

SearchFromURLController controller=new 
         SearchFromURLController();
System.assertEquals(true, controller.searched);
System.assertEquals(2, controller.accounts.size());

The second unit test method tests that the search is correctly executed when the user enters a search term. In this case, there is no interaction with the information on the page URL, so the test simply instantiates the controller and confirms that no search has been executed by the constructor.

SearchFromURLController controller=new SearchFromURLController();
System.assertEquals(false, controller.searched);

The test then sets the search term, executes the search method, and confirms the results.

controller.name='Unit';
System.assertEquals(null, controller.executeSearch());
System.assertEquals(2, controller.accounts.size());