Testing Leafs

Leafs are extremely easy to test; as long as you have a factory function that lest you inject any environmental dependencies (DB connections, constants, http bridge classes), you can easily create tests around any leaf you want. Leaf itself is extensively covered with unit tests; here is one to give a sample of how testing a leaf looks:

 
 
function makePoint(x, y, z) {
  return new Forest(
    {},
    {
      branches: p(x, y, z),
    }
  );
}
 
it('should have consistent branch values', () => {
  const box = new Forest(
    {},
    {
      branches: {
        topLeft: makePoint(0, 1, 0),
        topRight: makePoint(1, 1, 0),
        bottomLeft: makePoint(0, 0, 0),
        bottomRight: makePoint(1, 0, 0)
      },
    }
  );
  expect(box.version).toBe(0);
  expect(box.value).toEqual({
    topLeft: p(0, 1, 0),
    topRight: p(1, 1, 0),
    bottomLeft: p(0, 0, 0),
    bottomRight: p(1, 0, 0)
  });
  box.branch('topLeft.x').next(3);
  expect(box.value).toEqual({
    topLeft: p(3, 1, 0),
    topRight: p(1, 1, 0),
    bottomLeft: p(0, 0, 0),
    bottomRight: p(1, 0, 0)
  });
  expect(box.version).toBe(1);
  expect(box.branch('bottomLeft').version).toBe(0);
 
  box.branch('topRight.z').next(6);
  expect(box.value).toEqual({
    topLeft: p(3, 1, 0),
    topRight: p(1, 1, 6),
    bottomLeft: p(0, 0, 0),
    bottomRight: p(1, 0, 0)
  });
  expect(box.version).toBe(2);
  expect(box.branch('bottomLeft').version).toBe(0);
});

Last updated on April 8, 2023

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