Write marionette tests with JSON.

today_test.json

{
  "testcase": "should be show in header, highlighted day after tap today",
  "app": "app://calendar.gaiamobile.org",
  "operations": [
    {
      "target": "#today-css-selector",
      "condition": "document.querySelector('#today-css-selector').innerHTML === new Date().getDate()",
      "action": "tap"
    }
  ],
  "assert": [
    {
      "actual": "document.querySelector('#month-view-item').innerHTML",
      "expected": "new Date().getDatet()"
    }
  ]
}

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