Thanks for fixing this bug and adding a comprehensive test! I pushed a merge with main to resolve a trivial conflict, then I pushed a bunch of changes to the test - please double-check my work.

adding a comprehensive test

Thanks for adding all the missing tests to my comprehensive test 😻

I gave this some more thought and pushed more changes after I got greedy 😹

• No need to test ranges::destroy, ranges::destroy_n.
  • As noted by @frederick-vs-ja in iter_value_t<I> should always use direct-initialization #4233 (comment)
• Test more overloads of parallel inclusive_scan and transform_inclusive_scan.
  • Noticed while comparing serial to parallel.
• Drop unnecessary argument variations - this is compile-only.
  • I verified that all of the observable iter_move fixes are still detected by the remaining test lines.

I'm mirroring this to the MSVC-internal repo - please notify me if any further changes are pushed.

I had to push an additional commit to work around a newly-discovered bug, VSO-1946395 "/clr /std:c++20 /Od backend ICE for parallel std::find_end". This repros with VS 2022 17.9 Preview 4 x86 (didn't check x64) without your PR's changes - it's simply being found by the enhanced test coverage you're adding.

Thanks for fixing this bug and adding comprehensive test coverage! 🐞 🛠️ 😸