This is the first installment of a multi-PR series significantly
refactoring how highlights are being specified.
The end goal is to have a base set of 20 ish most common highlights,
and then specific files only need to add more groups to that as needed.
As a complicating factor, we also want to migrate to the new default
color scheme eventually. But by sharing a base set, that future PR
will hopefully be a lot smaller since a lot of tests will be migrated
just simply by updating the base set in place.
As a first step, fix the anti-pattern than Screen defaults to ignoring
highlights. Highlights are integral part of the screen state, not
something "extra" which we only test "sometimes". For now, we still
allow opt-out via the intentionally ugly
screen._default_attr_ids = nil
The end goal is to get rid of all of these eventually (which will be
easier as part of the color scheme migration)
Problem Description: In ex_mode, the default_grid.chars are not allocated, and subsequently,
the w_grid.target in curwin is not allocated to default_grid in update_screen. This leads to
a null pointer crash when the completion function is executed in ex_mode.
Solution: Set full_screen when in ex_mode to ensure that default_grid is allocated.
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.
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
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.
Problem:
`nvim -v` and `:version` prints system vimrc, fallback files, and compilation
info by default, which most people don't care about and just clutters up the
output.
Solution:
Omit extra info unless 'verbose' is set.
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")`.
This is essentially a convenience wrapper around the `pending()`
function, similar to `skip_fragile()` but more general-purpose.
Also remove `pending_win32` function as it can be replaced by
`skip(iswin())`.
* Reading from stdin on Windows is fixed in the same way as it was in
#8267.
* The file_read function was returning without filling the
destination buffer when it was called with a non-blocking file
descriptor.
This variant uses `fdopen()` which is not standard, but it fixes problem on my
system. In next commit `scriptin` will use `FileDescriptor*` from os/fileio in
place of `FILE*`.
