tree e19de5865447a1f3a612707001dc251285d474bf
parent 22800db42cf967708d371fc7143cd188430a036d
author Peng Liu <winner245@hotmail.com> 1742401691 -0400
committer Copybara-Service <copybara-worker@google.com> 1742401805 -0700

[libc++] Verify forward_list self-merging is a no-op (#129985)

https://wg21.link/LWG3088 requires that `forward_list::merge()` is a no-op when passed
`*this`, which aligns with the behavior of `list::merge`. Although libc++'s implementation
of `forward_list::merge()` already meets this requirement, there were no tests to verify
this behavior. This patch adds the necessary tests to ensure that self-merging remains a
no-op and prevents any future regressions on this.

Closes #104942.

GitOrigin-RevId: b350bc2c0b88488f6c4eb84aadd4e74c67ca9b06