Problem:
Crash from:
set cmdheight=0 redrawdebug=invalid
resize -1
Solution:
Do not invalidate first `p_ch` `msg_grid` rows in `update_screen` when
scrolling the screen down after displaying a message, because they may
be used later for drawing cmdline.
Fixes#22154
This is incorrect in the following scenario:
1. The language tree is Lua > Vim > Lua.
2. An edit simultaneously wipes out the `_regions` of all nodes, while
taking the Vim injection off-screen.
3. The Vim injection is not re-parsed, so the child Lua `_regions` is
still `nil`.
4. The child Lua is assumed, incorrectly, to occupy the whole document.
5. This causes the injections to be parsed again, resulting in Lua > Vim
> Lua > Vim.
6. Now, by the same process, Vim ends up with its range assumed over the
whole document. Now the parse is broken and results in broken
highlighting and poor performance.
It should be fine to instead treat an unparsed node as occupying
nothing (i.e. effectively non-existent). Since, either:
- The parent was just parsed, hence defining `_regions`
- The parent was not just parsed, in which case this node doesn't need
to be parsed either.
Also, the name `has_regions` is confusing; it seems to simply
mean the opposite of "root" or "full_document". However, this PR does
not touch it.
Fixes#24339
rust-analyzer sends "Invalid offset" error in such cases. Some other
servers handle it specially.
LSP spec mentions that "A range is comparable to a selection in an
editor". Most editors don't handle trailing newlines the same way
Neovim/Vim does, it's clearly visible if it's present or not. With that
in mind it's understandable why sending end position as simply the start
of the line after the last one is considered invalid in such cases.
Problem: Wrong curswant when clicking on empty line or with vsplits.
Solution: Don't check for ScreenCols[] before the start of the window
and handle empty line properly.
closes: vim/vim#1313203cd697d63
Previously, a screen cell would occupy 28+4=32 bytes per cell
as we always made space for up to MAX_MCO+1 codepoints in a cell.
As an example, even a pretty modest 50*80 screen would consume
50*80*2*32 = 256000, i e a quarter megabyte
With the factor of two due to the TUI side buffer, and even more when
using msg_grid and/or ext_multigrid.
This instead stores a 4-byte union of either:
- a valid UTF-8 sequence up to 4 bytes
- an escape char which is invalid UTF-8 (0xFF) plus a 24-bit index to a
glyph cache
This avoids allocating space for huge composed glyphs _upfront_, while
still keeping rendering such glyphs reasonably fast (1 hash table lookup
+ one plain index lookup). If the same large glyphs are using repeatedly
on the screen, this is still a net reduction of memory/cache
consumption. The only case which really gets worse is if you blast
the screen full with crazy emojis and zalgo text and even this case
only leads to 4 extra bytes per char.
When only <= 4-byte glyphs are used, plus the 4-byte attribute code,
i e 8 bytes in total there is a factor of four reduction of memory use.
Memory which will be quite hot in cache as the screen buffer is scanned
over in win_line() buffer text drawing
A slight complication is that the representation depends on host byte
order. I've tested this manually by compling and running this
in qemu-s390x and it works fine. We might add a qemu based solution
to CI at some point.
If you would insert element X at position j, then if you are moving that
same element X from position i < j, you should move it to position j -
1, because you are losing an element.
This error caused a gap to be left in the array, so that it looked like
[x, null, y] instead of [x, y], where len = 2. This triggered #25147.
Fixes: #25147
