2017-06-04: This test harness was used to track a performance bug in NUnit. The bug is present in NUnit versions v3.4.0 - v3.7.1 inclusive. NUnit 2.x is not affected.
2017-06-08: The bug has since been identified and resolved.
2017-06-22: A nightly build of NUnit v3 exists with the performance bug fix here.
2017-08-29: v3.8 has been released which contains the performance bug fix.
AoC stands for Advent of Code.