feat(neovim): split from Vim & revamp configuration

Neovim has acquired many features and diverged quite a bit from Vim over
the past few years that it was worth revisiting the configuration.

- Migrate configuration from Vim Script to Lua
- Use Home Manager for plugin management
- Prefer built-in Neovim features over external plugins
- Make use of TreeSitter and built-in LSP

files/.config/nvim/init.lua

@@ -0,0 +1,154 @@
+local augroup = vim.api.nvim_create_augroup("vimrc", { clear = true })
+
+-- {{{ General
+
+vim.opt.backup = true
+vim.opt.backupdir:remove(".")
+vim.opt.undofile = true
+vim.opt.ignorecase = true
+vim.opt.smartcase = true
+
+vim.g.tex_flavor = "latex"
+
+vim.cmd("silent! packadd! cfilter")
+
+-- See :h :DiffOrig
+vim.cmd([[
+  command! DiffOrig vert new | set bt=nofile | r ++edit # | 0d_ | diffthis
+    \ | wincmd p | diffthis
+]])
+
+-- }}}
+-- {{{ Editing
+
+vim.opt.expandtab = true
+vim.opt.shiftwidth = 2
+vim.opt.softtabstop = 2
+vim.opt.copyindent = true
+vim.opt.preserveindent = true
+vim.opt.formatoptions:append({ "m", "B" })
+vim.opt.fileencodings = {
+  "ucs-bom",
+  "utf-8",
+  "iso-2022-jp",
+  "euc-jp",
+  "cp932",
+  "default",
+  "latin1",
+}
+
+-- jump to the last known cursor position
+vim.api.nvim_create_autocmd("BufReadPost", {
+  group = augroup,
+  callback = function(opts)
+    local ft = vim.bo[opts.buf].filetype
+    local line = vim.api.nvim_buf_get_mark(opts.buf, '"')[1]
+    local in_range = 1 < line and line <= vim.api.nvim_buf_line_count(opts.buf)
+
+    if in_range and not ft:match("commit") then
+      vim.api.nvim_feedkeys([[g`"]], "nx", false)
+    end
+  end,
+})
+
+-- }}}
+-- {{{ UI
+
+vim.opt.colorcolumn = "81"
+vim.opt.foldenable = false
+vim.opt.inccommand = "split"
+vim.opt.lazyredraw = true
+vim.opt.mouse = "a"
+vim.opt.number = true
+vim.opt.showmatch = true
+vim.opt.title = true
+vim.opt.wildignorecase = true
+vim.opt.diffopt = {
+  "internal",
+  "filler",
+  "closeoff",
+  "algorithm:histogram",
+  "indent-heuristic",
+}
+
+vim.api.nvim_create_autocmd("TextYankPost", {
+  group = augroup,
+  pattern = "*",
+  callback = function(args)
+    vim.highlight.on_yank({
+      higroup = "Visual",
+      timeout = 300,
+    })
+  end,
+})
+
+vim.api.nvim_create_autocmd("QuickfixCmdPost", {
+  group = augroup,
+  pattern = [[\C[^lA-Z]*]],
+  command = "botright cwindow",
+})
+
+vim.api.nvim_create_autocmd("QuickfixCmdPost", {
+  group = augroup,
+  pattern = "l*",
+  command = "botright lwindow",
+})
+
+-- }}}
+-- {{{ Keybindings
+
+vim.g.mapleader = " "
+vim.g.maplocalleader = "\\"
+
+vim.keymap.set("n", "<Leader>b", "<Cmd>bmodified<CR>")
+
+vim.keymap.set({ "i", "s" }, "<Tab>", function()
+  if vim.snippet.active({ direction = 1 }) then
+    return "<Cmd>lua vim.snippet.jump(1)<CR>"
+  else
+    return "<Tab>"
+  end
+end, { expr = true })
+
+vim.keymap.set({ "i", "s" }, "<S-Tab>", function()
+  if vim.snippet.active({ direction = -1 }) then
+    return "<Cmd>lua vim.snippet.jump(-1)<CR>"
+  else
+    return "<S-Tab>"
+  end
+end, { expr = true })
+
+-- find merge conflict marker
+vim.keymap.set({ "n", "x", "o" }, "<Leader>fc", [[/\v^[<=>]{7}( .*<Bar>$)<CR>]])
+-- find whitespace errors
+vim.keymap.set({ "n", "x", "o" }, "<Leader>f ", [[/\s\+$\<Bar> \+\ze\t<CR>]])
+-- find full-width punctuation marks
+vim.keymap.set({ "n", "x", "o" }, "<Leader>f.", [[/\v(\.<Bar>．<Bar>。)<CR>]])
+vim.keymap.set({ "n", "x", "o" }, "<Leader>f,", [[/\v(,<Bar>，<Bar>、)<CR>]])
+vim.keymap.set({ "n", "x", "o" }, "<Leader>f!", [[f! /\v(!<Bar>！)<CR>]])
+vim.keymap.set({ "n", "x", "o" }, "<Leader>f!", [[f? /\v(\?<Bar>？)<CR>]])
+
+-- text objects
+vim.keymap.set("x", "al", "<Esc>0v$")
+vim.keymap.set("o", "al", "<Cmd>normal! 0v$<CR>")
+vim.keymap.set("x", "il", "<Esc>^vg_")
+vim.keymap.set("o", "il", "<Cmd>normal! ^vg_<CR>")
+vim.keymap.set("x", "ag", "gg0oG$")
+vim.keymap.set("o", "ag", [[<Cmd>exe "normal! m`"<Bar>keepjumps normal! ggVG<CR>]])
+
+-- toggles
+vim.keymap.set("n", "<Leader>ts", "<Cmd>setlocal spell! spell?<CR>")
+vim.keymap.set("n", "<Leader>tv", "<Cmd>call vimrc#toggle_virtualedit()<CR>")
+vim.keymap.set("n", "<Leader>tq", "<Cmd>call vimrc#toggle_textwidth()<CR>")
+vim.keymap.set("n", "<Leader>t#", "<Cmd>setlocal relativenumber! relativenumber?<CR>")
+vim.keymap.set("n", "<Leader>t ", "<Cmd>call vimrc#toggle_whitespace_check()<CR>")
+vim.keymap.set("n", "<Leader>t<Tab>", "<Cmd>call vimrc#toggle_whitespace_visibility()<CR>")
+
+-- 3-way merge
+vim.keymap.set("n", "<Leader>1", "<Cmd>diffget LOCAL<CR>")
+vim.keymap.set("n", "<Leader>2", "<Cmd>diffget BASE<CR>")
+vim.keymap.set("n", "<Leader>3", "<Cmd>diffget REMOTE<CR>")
+
+-- }}}
+
+-- vim:set foldmethod=marker:

files/.vim/ftplugin/fugitive.vim

@@ -1,3 +1,5 @@
 if !empty(mapcheck('q', 'n'))
   nunmap <buffer> q
 endif
+
+let b:editorconfig = v:false

nix/devshells/default.nix

@@ -13,7 +13,7 @@
 
         ansible = pkgs.callPackage ./ansible.nix { };
 
-        setup = pkgs.callPackage ./setup.nix { inherit (self'.packages) neovim; };
+        setup = pkgs.callPackage ./setup.nix { };
 
         quic = pkgs.callPackage ./quic.nix { };
       };

nix/devshells/setup.nix

@@ -4,7 +4,6 @@
   curl,
   emacs-nox,
   git,
-  neovim,
 }:
 
 mkShellNoCC {
@@ -13,6 +12,5 @@ mkShellNoCC {
     curl
     emacs-nox
     git
-    neovim
   ];
 }

nix/home/modules/vim.nix

@@ -33,6 +33,7 @@ in
         };
       };
     };
+    default = { };
     description = "Install the specified vim plugins.";
   };
 

nix/home/profiles/default.nix

@@ -10,6 +10,7 @@
     ./development.nix
     ./fonts.nix
     ./macos.nix
+    ./neovim.nix
     ./web.nix
   ];
 

nix/home/profiles/minimal.nix

@@ -34,14 +34,15 @@ in
       less
       ripgrep
       zsh-syntax-highlighting
-      myPkgs.neovim
     ];
 
     programs.direnv = {
       enable = mkDefault true;
       nix-direnv.enable = mkDefault true;
     };
 
+    dotfiles.profiles.neovim.enable = mkDefault true;
+
     dotfiles.manpages = {
       enable = mkDefault true;
       useSystemMan = mkDefault (!isNixOS);