vimrc/rust.vim

" from: https://sharksforarms.dev/posts/neovim-rust/
" Set completeopt to have a better completion experience
" :help completeopt
" menuone: popup even when there's only one match
" noinsert: Do not insert text until a selection is made
" noselect: Do not select, force user to select one from the menu
set completeopt=menuone,noinsert,noselect

" Avoid showing extra messages when using completion
set shortmess+=c

" Configure LSP through rust-tools.nvim plugin.
" rust-tools will configure and enable certain LSP features for us.
" See https://github.com/simrat39/rust-tools.nvim#configuration
lua <<EOF
local nvim_lsp = require'lspconfig'

local opts = {
    tools = { -- rust-tools options
        autoSetHints = true,
        hover_with_actions = true,
        inlay_hints = {
            show_parameter_hints = false,
            parameter_hints_prefix = "",
            other_hints_prefix = "",
        },
    },

    -- all the opts to send to nvim-lspconfig
    -- these override the defaults set by rust-tools.nvim
    -- see https://github.com/neovim/nvim-lspconfig/blob/master/CONFIG.md#rust_analyzer
    server = {}, -- rust-analyer options
}

require('rust-tools').setup(opts)
EOF

" Setup Completion
" See https://github.com/hrsh7th/nvim-cmp#basic-configuration
lua <<EOF
local cmp = require'cmp'
cmp.setup({
  -- Enable LSP snippets
  snippet = {
    expand = function(args)
        vim.fn["vsnip#anonymous"](args.body)
    end,
  },
  mapping = {
    ['<C-p>'] = cmp.mapping.select_prev_item(),
    ['<C-n>'] = cmp.mapping.select_next_item(),
    -- Add tab support
    ['<S-Tab>'] = cmp.mapping.select_prev_item(),
    ['<Tab>'] = cmp.mapping.select_next_item(),
    ['<C-d>'] = cmp.mapping.scroll_docs(-4),
    ['<C-f>'] = cmp.mapping.scroll_docs(4),
    ['<C-Space>'] = cmp.mapping.complete(),
    ['<C-e>'] = cmp.mapping.close(),
    ['<CR>'] = cmp.mapping.confirm({
      behavior = cmp.ConfirmBehavior.Insert,
      select = true,
    })
  },

  -- Installed sources
  sources = {
    { name = 'nvim_lsp' },
    { name = 'vsnip' },
    { name = 'path' },
    { name = 'buffer' },
  },
})
EOF

" Set updatetime for CursorHold
" 300ms of no cursor movement to trigger CursorHold
set updatetime=750
" Show diagnostic popup on cursor hold
autocmd CursorHold * lua vim.lsp.diagnostic.show_line_diagnostics()
" have a fixed column for the diagnostics to appear in
" this removes the jitter when warnings/errors flow in
set signcolumn=yes