Fix override

I am changing an existing test here, but I have done so only to ensure that it passes because the intended code path was hit. Currently in `master`, that test is identical to the one that precedes it (with the exception of the usage of the `shimOverrides` option). When that option is removed (or the targeted code path is disabled), the test still passes because a separate code path implements similar functionality. I tried to make the review process a little easier by separating the test modification into a separate commit. The two commits that follow address implementation details and only modify the test suite to add additional tests.