old_contents: #!/usr/bin/env node
  
  require ('proof')(5, prove)
  
  function prove (assert) {
      var rects = require('../../area.js')
  
      var a = new rects.Area(0, 5, 0, 5)
      var b = new rects.Area(0, 7, 0, 7)
      var c = new rects.Area(5, 10, 5, 10)
      var d = new rects.Area(15, 5, 0, 20)
  
      assert(b.containsPoint(2,2), true , "Square(0,7,0,7) contains point(2,2)")
      assert(b.containsPoint(0,0), true , "Square(0,7,0,7) contains point(0,0)")
      assert(b.containsPoint(8,8), false , "Square(0,7,0,7) doesn't contain point(8,8)")
  }
  
new_contents: #!/usr/bin/env node
  
  require ('proof')(4, prove)
  
  function prove (assert) {
      var rects = require('../../area.js')
  
      var a = new rects.Area(-10, 5, -5, 0)
      var b = new rects.Area(0, 7, 0, 7)
  
      assert(a.containsPoint(-2, -2), true, "Square(-10, 5, -5, 0) contains point(-2, -2)")
      assert(b.containsPoint(2,2), true , "Square(0,7,0,7) contains point(2,2)")
      assert(b.containsPoint(0,0), true , "Square(0,7,0,7) contains point(0,0)")
      assert(b.containsPoint(8,8), false , "Square(0,7,0,7) doesn't contain point(8,8)")
  }
  
subject: Test negative points.