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HTML

              
                <div id="mocha"><p><a href=".">Index</a></p></div>
  <div id="messages"></div>
  <div id="fixtures"></div>
              
            
!

CSS

              
                @charset "utf-8";

body {
  margin:0;
}

#mocha {
  font: 20px/1.5 "Helvetica Neue", Helvetica, Arial, sans-serif;
  margin: 60px 50px;
}

#mocha ul,
#mocha li {
  margin: 0;
  padding: 0;
}

#mocha ul {
  list-style: none;
}

#mocha h1,
#mocha h2 {
  margin: 0;
}

#mocha h1 {
  margin-top: 15px;
  font-size: 1em;
  font-weight: 200;
}

#mocha h1 a {
  text-decoration: none;
  color: inherit;
}

#mocha h1 a:hover {
  text-decoration: underline;
}

#mocha .suite .suite h1 {
  margin-top: 0;
  font-size: .8em;
}

#mocha .hidden {
  display: none;
}

#mocha h2 {
  font-size: 12px;
  font-weight: normal;
  cursor: pointer;
}

#mocha .suite {
  margin-left: 15px;
}

#mocha .test {
  margin-left: 15px;
  overflow: hidden;
}

#mocha .test.pending:hover h2::after {
  content: '(pending)';
  font-family: arial, sans-serif;
}

#mocha .test.pass.medium .duration {
  background: #c09853;
}

#mocha .test.pass.slow .duration {
  background: #b94a48;
}

#mocha .test.pass::before {
  content: '✓';
  font-size: 12px;
  display: block;
  float: left;
  margin-right: 5px;
  color: #00d6b2;
}

#mocha .test.pass .duration {
  font-size: 9px;
  margin-left: 5px;
  padding: 2px 5px;
  color: #fff;
  -webkit-box-shadow: inset 0 1px 1px rgba(0,0,0,.2);
  -moz-box-shadow: inset 0 1px 1px rgba(0,0,0,.2);
  box-shadow: inset 0 1px 1px rgba(0,0,0,.2);
  -webkit-border-radius: 5px;
  -moz-border-radius: 5px;
  -ms-border-radius: 5px;
  -o-border-radius: 5px;
  border-radius: 5px;
}

#mocha .test.pass.fast .duration {
  display: none;
}

#mocha .test.pending {
  color: #0b97c4;
}

#mocha .test.pending::before {
  content: '◦';
  color: #0b97c4;
}

#mocha .test.fail {
  color: #c00;
}

#mocha .test.fail pre {
  color: black;
}

#mocha .test.fail::before {
  content: '✖';
  font-size: 12px;
  display: block;
  float: left;
  margin-right: 5px;
  color: #c00;
}

#mocha .test pre.error {
  color: #c00;
  max-height: 300px;
  overflow: auto;
}

#mocha .test .html-error {
  overflow: auto;
  color: black;
  line-height: 1.5;
  display: block;
  float: left;
  clear: left;
  font: 12px/1.5 monaco, monospace;
  margin: 5px;
  padding: 15px;
  border: 1px solid #eee;
  max-width: 85%; /*(1)*/
  max-width: -webkit-calc(100% - 42px);
  max-width: -moz-calc(100% - 42px);
  max-width: calc(100% - 42px); /*(2)*/
  max-height: 300px;
  word-wrap: break-word;
  border-bottom-color: #ddd;
  -webkit-box-shadow: 0 1px 3px #eee;
  -moz-box-shadow: 0 1px 3px #eee;
  box-shadow: 0 1px 3px #eee;
  -webkit-border-radius: 3px;
  -moz-border-radius: 3px;
  border-radius: 3px;
}

#mocha .test .html-error pre.error {
  border: none;
  -webkit-border-radius: 0;
  -moz-border-radius: 0;
  border-radius: 0;
  -webkit-box-shadow: 0;
  -moz-box-shadow: 0;
  box-shadow: 0;
  padding: 0;
  margin: 0;
  margin-top: 18px;
  max-height: none;
}

/**
 * (1): approximate for browsers not supporting calc
 * (2): 42 = 2*15 + 2*10 + 2*1 (padding + margin + border)
 *      ^^ seriously
 */
#mocha .test pre {
  display: block;
  float: left;
  clear: left;
  font: 12px/1.5 monaco, monospace;
  margin: 5px;
  padding: 15px;
  border: 1px solid #eee;
  max-width: 85%; /*(1)*/
  max-width: -webkit-calc(100% - 42px);
  max-width: -moz-calc(100% - 42px);
  max-width: calc(100% - 42px); /*(2)*/
  word-wrap: break-word;
  border-bottom-color: #ddd;
  -webkit-box-shadow: 0 1px 3px #eee;
  -moz-box-shadow: 0 1px 3px #eee;
  box-shadow: 0 1px 3px #eee;
  -webkit-border-radius: 3px;
  -moz-border-radius: 3px;
  border-radius: 3px;
}

#mocha .test h2 {
  position: relative;
}

#mocha .test a.replay {
  position: absolute;
  top: 3px;
  right: 0;
  text-decoration: none;
  vertical-align: middle;
  display: block;
  width: 15px;
  height: 15px;
  line-height: 15px;
  text-align: center;
  background: #eee;
  font-size: 15px;
  -webkit-border-radius: 15px;
  -moz-border-radius: 15px;
  border-radius: 15px;
  -webkit-transition:opacity 200ms;
  -moz-transition:opacity 200ms;
  -o-transition:opacity 200ms;
  transition: opacity 200ms;
  opacity: 0.3;
  color: #888;
}

#mocha .test:hover a.replay {
  opacity: 1;
}

#mocha-report.pass .test.fail {
  display: none;
}

#mocha-report.fail .test.pass {
  display: none;
}

#mocha-report.pending .test.pass,
#mocha-report.pending .test.fail {
  display: none;
}
#mocha-report.pending .test.pass.pending {
  display: block;
}

#mocha-error {
  color: #c00;
  font-size: 1.5em;
  font-weight: 100;
  letter-spacing: 1px;
}

#mocha-stats {
  position: fixed;
  top: 15px;
  right: 10px;
  font-size: 12px;
  margin: 0;
  color: #888;
  z-index: 1;
}

#mocha-stats .progress {
  float: right;
  padding-top: 0;

  /**
   * Set safe initial values, so mochas .progress does not inherit these
   * properties from Bootstrap .progress (which causes .progress height to
   * equal line height set in Bootstrap).
   */
  height: auto;
  -webkit-box-shadow: none;
  -moz-box-shadow: none;
  box-shadow: none;
  background-color: initial;
}

#mocha-stats em {
  color: black;
}

#mocha-stats a {
  text-decoration: none;
  color: inherit;
}

#mocha-stats a:hover {
  border-bottom: 1px solid #eee;
}

#mocha-stats li {
  display: inline-block;
  margin: 0 5px;
  list-style: none;
  padding-top: 11px;
}

#mocha-stats canvas {
  width: 40px;
  height: 40px;
}

#mocha code .comment { color: #ddd; }
#mocha code .init { color: #2f6fad; }
#mocha code .string { color: #5890ad; }
#mocha code .keyword { color: #8a6343; }
#mocha code .number { color: #2f6fad; }

@media screen and (max-device-width: 480px) {
  #mocha {
    margin: 60px 0px;
  }

  #mocha #stats {
    position: absolute;
  }
}
              
            
!

JS

              
                (function(exports) {
  "use strict";

  function Cow(name) {
    this.name = name || "Anon cow";
  }
  exports.Cow = Cow;

  Cow.prototype = {
    greets: function(target) {
      if (!target)
        throw new Error("missing target");
      return this.name + " greets " + target;
    }
  };
})(this);

mocha.setup('bdd');

var expect = chai.expect;
 
describe("Cow", function() {
  describe("constructor", function() {
    it("should have a default name", function() {
      var cow = new Cow();
      console.log("About to test default name.");
      expect(cow.name).to.equal("Anon cow");
      console.log("Test successful!");
    });

    it("should set cow's name if provided", function() {
      var cow = new Cow("Kate");
      expect(cow.name).to.equal("Kate");
    });
  });

  describe("#greets", function() {
    it("should throw if no target is passed in", function() {
      expect(function() {
        (new Cow()).greets();
      }).to.throw(Error);
    });

    it("should greet passed target", function() {
      var greetings = (new Cow("Kate")).greets("Baby");
      expect(greetings).to.equal("Kate greets Baby");
    });
  });
});

mocha.run();
              
            
!
999px
What did the colon say to the semicolon? Stop winking at me.

Console