I know a test case reducer as a thing that takes a long bug reproduction sequence (like, do a, b, c, d, e, f and then X happens) and turns it into a shorter lis

I know a test case reducer as a thing that takes a long bug reproduction sequence (like, do a, b, c, d, e, f and then X happens) and turns it into a shorter list (just do a, d, f and then X happens) Which is useful. You get a log from prod, and then you automatically compress it to the minimal steps to trigger a bug which usually gets you halfway to understanding the issue. See also the work by andreas zeller: https://blog.acolyer.org/2015/11/16/simplifying-and-isolating-failure-inducing-input/ https://blog.acolyer.org/2015/11/16/simplifying-and-isolatin... Though I also haven’t read the code, so this might be about something else entirely!