Problem: Default color scheme is suboptimal.
Solution: Start using new color scheme. Introduce new `vim` color scheme
for opt-in backward compatibility.
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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.
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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.
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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).
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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.
connection from any channel or stdio will unblock
remote_ui_wait_for_attach. Wait on stdio only if
only —embed specified, if both —embed and
—listen then wait on any channel.
Extend the capabilities of is_os to detect more platforms such as
freebsd and openbsd. Also remove `iswin()` helper function as it can be
replaced by `is_os("win")`.
The old behaviour (e.g. via `set display-=msgsep`) will not be available.
Assuming that messages always are being drawn on msg_grid
(or not drawn at all, and forwarded to `ext_messages` enabled UI)
will allows some simplifcations and enhancements moving forward.
Currently `nvim -u NORC --cmd "set display-=msgsep"` will still allocate the
message grid and remove it just afterwards. While inefficient, we must
make sure update_screen() re-validates the default_grid completely when
this happens.
Fix some invalid logic: don't reallocate msg_grid on resize when the grid is not
used.
Elide a too early ui_flush() on startup, which caused an invalid cursor
position to be used.
Callers can instead specify `args_rm={'--headless'}`.
TODO: should `nvim_argv` have "--headless" by default? Need to inspect
some uses of spawn(nvim_argv) ...
By historical accident, Nvim defaults to background=light. So on a dark
background, `:colorscheme default` looks completely wrong.
The "smart" logic that Vim uses is confusing for anyone who uses Vim on
multiple platforms, so rather than mimic that, pick the (hopefully) most
common default.
- Since Neovim is dark-powered, we assume most users have dark backgrounds.
- Most of the GUIs tend to have a dark background by default.
ref #6289
NB: existing `color default` test was actually enough to trigger the bug,
when ext_newgrid=false is used. I created the `:hi Normal` test as
I thought the builtin colors wouldn't set Normal (unless 'bg' is changed)
But as the root cause actually comes from `:hi Normal`, it makes sense
to still add the separate test (if `color default` here gets optimized to
become a no-op, or something).
Give embeders a chance to set up nvim, by processing a request before
startup. This allows an external UI to show messages and prompts from
--cmd and buffer loading (e.g. swap files)
