patch 9.1.0116: win_split_ins may not check available room Commit: https://github.com/vim/vim/commit/0fd44a5ad81ade342cb54d8984965bdedd2272c8 Author: Sean Dewar <6256228+seandewar@users.noreply.github.com> Date: Tue Feb 20 20:28:15 2024 +0100 patch 9.1.0116: win_split_ins may not check available room Problem: win_split_ins has no check for E36 when moving an existing window Solution: check for room and fix the issues in f_win_splitmove() (Sean Dewar) win_split_ins has no check for E36 when moving an existing window, allowing for layouts with many overlapping zero-sized windows to be created (which may also cause drawing issues with tablines and such). f_win_splitmove also has some bugs. So check for room and fix the issues in f_win_splitmove. Handle failure in the two relevant win_split_ins callers by restoring the original layout, and factor the common logic into win_splitmove. Don't check for room when opening an autocommand window, as it's a temporary window that's rarely interacted with or drawn anyhow, and is rather important for some autocommands. Issues fixed in f_win_splitmove: - Error if splitting is disallowed. - Fix heap-use-after-frees if autocommands fired from switching to "targetwin" close "wp" or "oldwin". - Fix splitting the wrong window if autocommands fired from switching to "targetwin" switch to a different window. - Ensure -1 is returned for all errors. Also handle allocation failure a bit earlier in make_snapshot (callers, except win_splitmove, don't really care if a snapshot can't be made, so just ignore the return value). Note: Test_smoothscroll_in_zero_width_window failed after these changes with E36, as it was using the previous behaviour to create a zero-width window. I've fixed the test such that it fails with UBSAN as expected when v9.0.1367 is reverted (and simplified it too). related: #14042 Signed-off-by: Sean Dewar <6256228+seandewar@users.noreply.github.com> Signed-off-by: Christian Brabandt <cb@256bit.org>

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