Problem: Redrawing can be improved when inserting/deleting lines with 'number'.
Solution: Only redraw the number column of lines below changed lines.
Add a test as this wasn't previously tested.
(zeertzjq)
closes: vim/vim#13985ae07ebc04b
Problem: LineNrAbove and LineNrBelow background wrong on wrapped lines.
Solution: Update number column also for wrapped part of a line.
(zeertzjq)
closes: vim/vim#13974ebfd856cfd
Cherry-pick test_number.vim changes from patch 9.0.0626.
Problem: Tests using term_wait() can still be flaky.
Solution: Increase the wait time when rerunning a test. (James McCoy,
closesvim/vim#5899) Halve the initial times to make tests run faster
when there is no rerun.
6a2c5a7dd5
Co-authored-by: Bram Moolenaar <Bram@vim.org>
