The motivation for this update is Issue #15365, where background=light
is not properly set for Nvim running from an Nvim :terminal. This can be
encountered when e.g., opening a terminal to make git commits, which
opens EDITOR=nvim in the nested terminal.
Under the implementation of this commit, the OSC response always
indicates a black or white foreground/background. While this may not
reflect the actual foreground/background color, it permits 'background'
to be retained for a nested Nvim instance running in the terminal
emulator. The behaviour matches Vim.
This commit implements a new TermRequest autocommand event and has Neovim
emit this event when children of terminal buffers emit an OSC or DCS sequence
libvterm does not handle.
The TermRequest autocommand event has additional data in the
v:termrequest variable.
Co-authored-by: Gregory Anders <greg@gpanders.com>
Since execl() is a variadic function, it requries a NULL-terminal to
indicate the end of its argument list, c.f. exec(3)
> The first argument, by convention, should point to the filename
> associated with the file being executed. The list of arguments *must*
> be terminated by a null pointer
This fixes the failure seen on aarch64 and i386, due to garbage data
being considered part of the variadic arguments.
Problem: Updating default color scheme produced some feedback.
Solution: Address the feedback.
Outline of the changes:
- Colors `Grey1` and `Grey2` are made a little bit more extreme (dark -
darker, light - lighter) to increase overall contrast.
- `gui` colors are treated as base with `cterm` colors falling back to
using 0-15 colors which come from terminal emulator.
- Update highlight group definition to not include attribute definition
if it is intended to staty uncolored.
- Tweak some specific highlight groups.
- Add a list of Neovim specific highlight groups which are now defined
differently in a breaking way.
- Minor tweaks in several other places related to default color scheme.
Problem:
Unlike termopen(), nvim_open_term() PTYs do not carriage-return the
cursor on newline ("\n") input.
nvim --clean
:let chan_id = nvim_open_term(1, {})
:call chansend(chan_id, ["here", "are", "some", "lines"])
Actual behavior:
here
are
some
lines
Expected behaviour:
here
are
some
lines
Solution:
Add `force_crlf` option, and enable it by default.
This is the command invoked repeatedly to make the changes:
:%s/^\(.*\)|\%(\*\(\d\+\)\)\?$\n\1|\%(\*\(\d\+\)\)\?$/\=submatch(1)..'|*'..(max([str2nr(submatch(2)),1])+max([str2nr(submatch(3)),1]))/g
Rather than writing the synchronized update begin and end sequences into
the TUI's internal buffer (where it is later flushed to the TTY), write
these sequences directly to the TTY before and after the TUI's internal
buffer is itself flushed to the TTY.
This guarantees that a synchronized update is always used when we are
actually sending data to the TTY. This means we do not need to keep
track of the TUI's "dirty" state (any sequences which affect the TUI
state will be written in the TUI's internal buffer, which is now
guaranteed to only ever be written when a synchronized update is
active).
Currently, the value of $COLORTERM in :terminal in tests depends on
outer environment because of 'notermguicolors'.
If $COLORTERM is not set in :terminal, an inner Nvim instance will try
to detect 'termguicolors' support, which may interfere with tests.
So set 'termguicolors' in outer Nvim instance unless $COLORTERM needs to
be overridden, and unset it in inner Nvim instance when running TUI.
Set 'notermguicolors' in tests which spawn a child Nvim process to force
existing tests to use 16 colors. Also refactor the child process
invocation to make things a little bit less messy.
Problem: Default color scheme is suboptimal.
Solution: Start using new color scheme. Introduce new `vim` color scheme
for opt-in backward compatibility.
------
Main design ideas
- Be "Neovim branded".
- Be minimal for 256 colors with a bit more shades for true colors.
- Be accessible through high enough contrast ratios.
- Be suitable for dark and light backgrounds via exchange of dark and
light palettes.
------
Palettes
- Have dark and light variants. Implemented through exporeted
`NvimDark*` and `NvimLight*` hex colors.
- Palettes have 4 shades of grey for UI elements and 6 colors (red,
yellow, green, cyan, blue, magenta).
- Actual values are computed procedurally in Oklch color space based on
a handful of hyperparameters.
- Each color has a 256 colors variant with perceptually closest color.
------
Highlight groups
Use:
- Grey shades for general UI according to their design.
- Bold text for keywords (`Statement` highlight group). This is an
important choice to increase accessibility for people with color
deficiencies, as it doesn't rely on actual color.
- Green for strings, `DiffAdd` (as background), `DiagnosticOk`, and some
minor text UI elements.
- Cyan as main syntax color, i.e. for function usage (`Function`
highlight group), `DiffText`, `DiagnosticInfo`, and some minor text UI
elements.
- Red to generally mean high user attention, i.e. errors; in particular
for `ErrorMsg`, `DiffDelete`, `DiagnosticError`.
- Yellow very sparingly only with true colors to mean mild user
attention, i.e. warnings. That is, `DiagnosticWarn` and `WarningMsg`.
- Blue very sparingly only with true colors as `DiagnosticHint` and some
additional important syntax group (like `Identifier`).
- Magenta very carefully (if at all).
------
Notes
- To make tests work without relatively larege updates, each one is
prepended with an equivalent of the call `:colorscheme vim`.
Plus some tests which spawn new Neovim instances also now use 'vim'
color scheme.
In some cases tests are updated to fit new default color scheme.
Some escape sequences (in particular, OSC 52 paste responses) can be
very large, even unbounded in length. These can easily overflow
termkey's internal buffer. In order to process these long sequences,
dynamically grow termkey's internal buffer.
libtermkey does not interpret OSC sequences that end with a BEL (0x07)
instead of an ST (0x1b 0x5c) terminator. This causes these tests to fail
since the OSC response is now parsed via libtermkey. Change the tests to
use the ST terminator to appease libtermkey.
The 'arabicshape' feature of vim is a transformation of unicode text to
make arabic and some related scripts look better at display time. In
particular the content of a cell will be adjusted depending on the
(original) content of the cells just before and after it.
This is implemented by the arabic_shape() function in nvim. Before this
commit, shaping was invoked in four different contexts:
- when rendering buffer text in win_line()
- in line_putchar() for rendering virtual text
- as part of grid_line_puts, used by messages and statuslines and
similar
- as part of draw_cmdline() for drawing the cmdline
This replaces all these with a post-processing step in grid_put_linebuf(),
which has become the entry point for all text rendering after recent
refactors.
An aim of this is to make the handling of multibyte text yet simpler.
One of the main reasons multibyte chars needs to be "parsed" into
codepoint arrays of composing chars is so that these could be inspected
for the purpose of shaping. This can likely be vastly simplified in many
contexts where only the total length (in bytes) and width of composed
char is needed.
