title: Ruby on Rails: Running Tests
body: <p>When I want to run all my unit tests, I run rake test:units. To run all my functional tests, I run rake test:functionals. If I want to run all the test cases in one file, I run</p>
  
  <p>ruby test/unit/username_test.rb</p>
  
  <p>A few people have been telling me I should run rake instead such as</p>
  
  <p>rake test:units TEST=test/unit/username_test.rb</p>
  
  <p>For running tests, they say I should always run rake. I know I should run rake if I'm testing all my unit tests. But what if it's just one file or one particular test method in a file that I'm testing? Should I still use rake? Is there any difference between the two? Do I get any benefit from running rake over ruby? Is there any disadvantage to running ruby rather than rake?</p>