An easy way to manage unit test amenities. Originally posted in https://github.com/stevemao/better-than-before/issues/6

test-amenities.js

const amenityDefs = {
  dbConn: {
    provide() { db.connect(login); },
    dispose() { db.disconnect(); },
  },
  dummyTable: {
    provide() { db.createTable('dummy', dummySchema); },
    dispose() { db.dropTable('dummy'); },
  },
  dummyData: {
    provide() { db.tbl('dummy').restore(dummyData); },
    dispose() { db.tbl('dummy').restore([]); },
  },
};

const testDefs = {};
(function defTests(arr) {
  var prevTestFunc;
  arr.forEach(function (spec) {
    if ((typeof spec) !== 'function') {
      return Object.assign(prevTestFunc, spec);
    }
    prevTestFunc = spec;
    testDefs[spec.name] = spec;
    test(spec.name, spec);
  });
}([

  function connectToDatabase() {
    assert.ok(!!db.socket);
  },
  { need: [ 'dbConn' ] },

  function measureTableLength() {
    var cnt = db.tbl('dummy').countItems();
    assert.strictEqual((typeof cnt), 'number');
    assert.ok(cnt >= 0);
  },
  { need: [ 'dbConn', 'dummyTable' ] },

  function lookupFirstItem() {
    var item = db.tbl('dummy').getByProp('id', 1);
    assert.strictEqual(item.type, 'comment');
  },
  { need: [ 'dbConn', 'dummyTable', 'dummyData' ] },

]));


function adjustAmenities(need) {
  Object.keys(currentAmenities).forEach((amn) => {
    if (need.indexOf(amn) >= 0) { return; }
    amenityDefs[amn].dispose();
    delete currentAmenities[amn];
  });
  need.forEach((amn) => {
    if (objHas(currentAmenities, amn)) { return; }
    currentAmenities[amn] = amenityDefs[amn].provide();
  });
}

test.beforeEach(function (testId) {
  var testFunc = testDefs[testId],
    requiredAmenities = testFunc.need;
  adjustAmenities(requiredAmenities);
});

test.after(() => { adjustAmenities([]); });