Remove consecutive discards heuristic #2290
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We have a heuristic in
ConjectureDatawhich turns long sequences of discards into invalid test cases. This PR removes that heuristic.Justification
This heuristic was introduced in #2030 as a workaround to performance problems. Since #2185 we no longer hit those performance problems because we mark parts of the tree with discards in them as not worth exploring, and
generate_novel_prefixwill steer us clear of there. This is a better solution: We don't artificially make some discards invalid, but we don't spend ages trying to draw many equivalent tests.Meanwhile, leaving it in is a bit of a footgun - I lost about 20 minutes earlier to debugging something that turned out to be the result of triggering this (and in that case I was perfectly fine with long series of discards).