如何指定没有输入的测试用例

Question

For example: I want to make a case test of the "Logout" function.. What can I put in the "input"? The click in the Logout button?, because the method does not receive any parameter.. The expected output would be going back to the Login page.

public String logout() {
  FacesContext.getCurrentInstance().getExternalContext().invalidateSession();
  return "/Login?faces-redirect=true";
}

This must be a very dumb question, but I'm not used to do test cases so I'm a little lost.

Answer 1

The FacesContext is a global variable. Ie you could inject a mock into it. I assume using Mockito:

@Test
public testLogout()
{
   //setup
   FacesContext context = Mockito.mock(FacesContext.class);
   ExternalContext externalContext = Mockito.mock(ExternalContext.class);
   FacesContext.setCurrentInstance(context);
   when(context.getExternalContext()).thenReturn(externalContext);
   //act
   bean.logout();
   //verify
   verify(externalContext).invalidateSession();
}

This is not the best approach, but because of bad designed JSF, you should use the global variables and implicit dependencies. The proper solution would include IoC container and dependency injection.

Answer 2

From a more theoritical point of view, a test case is:

• initial situation/configuration (setup)
• action (the one you want to test) with optional parameters (input)
• expected outcome/output

If you are testing "login", your situation is "I am logged out" and your input is "log/pwd"

If you are testing "logout", your situation is "I am logged in" and you have no input