Nice javascript unit testing (jasmine) trick: which spec takes the most time?

test.js

describe("test suite that you wanna perf", function() {
  beforeEach(function() {
    this.start = performance.now();
  });

  afterEach(function() {
    console.log(jasmine.getEnv().currentSpec.description, performance.now() - this.start);
  });
});