Chai expect tests are all backwards

[scholarsmate]

When using chai expect, the order is supposed to be expect(<the thing we're testing>).<expectation>. Right now we have checks that look like this expect(3).to.equal(segment.length), which should be expect(segment.length).to.equal(3).

This swapping of values is an easy thing to fix and check, but there are many expect statements throughout the test suite, so it will be somewhat time consuming.