title: How does testing framework mocha knows, which source file I am testing?
body: <p>talking about --> <a href="http://mochajs.org/" rel="nofollow">http://mochajs.org/</a></p>
  
  <p>my app is not a node app, it's a web app, I am trying to use tdd approach using mocha and chai.</p>
  
  <p>I am confused, on how does mocha understand, that this x test case file is for x source file?</p>
  
  <p>e.g. 
  <strong>source file is userArea.js</strong></p>
  
  <p><strong>test file will be in /test folder --> userArea.spec.js</strong> (this will have test cases)</p>
  
  <p>When I run test cases through mocha, how does it identify, for what source files, I am running tests?</p>