Ultimately this isn't testing a whole lot other than that there are no repeats in the list of defined colors and that the wraparound logic works as expected, but it does include the framework for testing colors for adequate contrast. After doing some legwork on this, I don't think we're likely to come up with a list of more than 3-4 colors that actually do have mutual adequate contrast, so most of the rest of this is kind of moot, but it doesn't hurt to have it around if we want to revisit the topic in the future.
Ultimately this isn't testing a whole lot other than that there are no repeats in the list of defined colors and that the wraparound logic works as expected, but it does include the framework for testing colors for adequate contrast. After doing some legwork on this, I don't think we're likely to come up with a list of more than 3-4 colors that actually do have mutual adequate contrast, so most of the rest of this is kind of moot, but it doesn't hurt to have it around if we want to revisit the topic in the future.