bfredl e656d7be2e perf(tui): faster implementation of terminfo
The processing of terminfo can be separated into two steps:

1. The initialization of terminfo, which includes trying to find $TERM
   in a terminfo database file. As a fallback, common terminfo
   definitions are compiled in. After this, we apply a lot of ad-hoc
   patching to cover over limitations of terminfo.

2. While processing updates from nvim, actually using terminfo strings
   and formatting them with runtime values. for this part, terminfo
   essentially is a hyper-enhanced version of snprintf(), including
   a sm0l stack based virtual machine which can manipulate the runtime
   parameters.

This PR completely replaces libuniblium for step 2, with code
vendored from NetBSD's libtermkey which has been adapted to use typesafe
input parameters and to write into an output buffer in place.

The most immedatiate effects is a performance enhancement of
update_attrs() which is a very hot function when profiling the
TUI-process part of screen updates. In a stupid microbenchmark
(essentially calling nvim__screenshot over and over in a loop) this
leads to a speedup of ca 1.5x for redrawing the screen on the TUI-side.
What this means in practise when using nvim as a text editor is probably
no noticible effect at all, and when reabusing nvim as idk a full screen
RGB ASCII art rendrer maybe an increase from 72 to 75 FPS LMAO.

As nice side-effect, reduce the usage of unibilium to initialization only..
which will make it easier to remove, replace or make unibilium optional,
adressing #31989. Specifically, the builtin fallback doesn't use
unibilium at all, so a unibilium-free build is in principle possible
if the builtin definitions are good enough.

As a caveat, this PR doesn't touch libtermkey at all, which still has a
conditional dependency on unibilium. This will be investigated in a
follow-up PR

Note: the check of $TERMCOLOR was moved from tui/tui.c to
_defaults.lua in d7651b27d5 as we want to
skip the logic in _defaults.lua if the env var was set, but there
is no harm in TUI getting the right value when the TUI is trying to
initialize its terminfo shenanigans. Also this check is needed when
a TUI connects to a `--headless` server later, which will observe
a different $TERMCOLOR value than the nvim core process itself.
2025-10-18 11:36:16 +02:00

Neovim

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Neovim is a project that seeks to aggressively refactor Vim in order to:

See the Introduction wiki page and Roadmap for more information.

Features

See :help nvim-features for the full list, and :help news for noteworthy changes in the latest version!

Install from package

Pre-built packages for Windows, macOS, and Linux are found on the Releases page.

Managed packages are in Homebrew, Debian, Ubuntu, Fedora, Arch Linux, Void Linux, Gentoo, and more!

Install from source

See BUILD.md and supported platforms for details.

The build is CMake-based, but a Makefile is provided as a convenience. After installing the dependencies, run the following command.

make CMAKE_BUILD_TYPE=RelWithDebInfo
sudo make install

To install to a non-default location:

make CMAKE_BUILD_TYPE=RelWithDebInfo CMAKE_INSTALL_PREFIX=/full/path/
make install

CMake hints for inspecting the build:

  • cmake --build build --target help lists all build targets.
  • build/CMakeCache.txt (or cmake -LAH build/) contains the resolved values of all CMake variables.
  • build/compile_commands.json shows the full compiler invocations for each translation unit.

Transitioning from Vim

See :help nvim-from-vim for instructions.

Project layout

├─ cmake/           CMake utils
├─ cmake.config/    CMake defines
├─ cmake.deps/      subproject to fetch and build dependencies (optional)
├─ runtime/         plugins and docs
├─ src/nvim/        application source code (see src/nvim/README.md)
│  ├─ api/          API subsystem
│  ├─ eval/         Vimscript subsystem
│  ├─ event/        event-loop subsystem
│  ├─ generators/   code generation (pre-compilation)
│  ├─ lib/          generic data structures
│  ├─ lua/          Lua subsystem
│  ├─ msgpack_rpc/  RPC subsystem
│  ├─ os/           low-level platform code
│  └─ tui/          built-in UI
└─ test/            tests (see test/README.md)

License

Neovim contributions since b17d96 are licensed under the Apache 2.0 license, except for contributions copied from Vim (identified by the vim-patch token). See LICENSE for details.

Vim is Charityware.  You can use and copy it as much as you like, but you are
encouraged to make a donation for needy children in Uganda.  Please see the
kcc section of the vim docs or visit the ICCF web site, available at these URLs:

        https://iccf-holland.org/
        https://www.vim.org/iccf/
        https://www.iccf.nl/

You can also sponsor the development of Vim.  Vim sponsors can vote for
features.  The money goes to Uganda anyway.
Description
Vim-fork focused on extensibility and usability
Readme 478 MiB
Languages
Vim Script 40.8%
Lua 30.8%
C 27.6%
CMake 0.4%
Shell 0.1%
Other 0.1%