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var myObj = {
   name: "Aurelio De Rosa",
   items: []
}

QUnit.module('My module', {
   setup: function() {
      myObj.items = [1, 2, 3];
   },
   teardown: function() {
      for (var prop in myObj) {
         if (prop !== 'name' && prop !== 'items') {
            delete myObj[prop];
         }
      }
   }
});

QUnit.test('Test 1', function(assert) {
   expect(2);

   // Set a new property of the myObj object
   myObj.color = 'red';

   assert.strictEqual(myObj.items.length, 3, 'The setup function has pushed 3 elements');
   assert.deepEqual(myObj.items, [1, 2, 3], 'The setup function has pushed the expected elements');
});

QUnit.test('Test 2', function(assert) {
   expect(1);

   assert.ok(!myObj.color, 'The teardown function removed the color property');
});
<div id="qunit"></div>
<div id="qunit-fixture"></div>

              

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