What is the best way test to test simple logout and automatically logout with Protractor

What is the best way to test those scenarios:

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  Simple logout

  
  
  
  
  • How we can configure protractor to run some spec as latest? (Login configured in onPrepare())
  
  
  • Or Its ok, to do login, logout and after it login again because we have another test to run.
  
  
  
  


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  Logout by timeout

  
  
  
  
  • Just wait for time out and find some on the web? Or Protractor has some features to do it nice?
  
  
  
  

And the main question how to combine those test together?