nvim/lua/Plugin/coc.lua

local G = require('G')

G.g['coc_global_extensions'] = {
  "coc-clangd",
  "coc-python",
  "coc-json",
  "coc-lua",

  "coc-translator",
  "coc-yank",
  "coc-pairs",
  "coc-explorer",
  "coc-lists",
}

-- Having longer updatetime (default is 4000 ms = 4s) leads to noticeable
-- delays and poor user experience
G.opt.updatetime = 300

-- Always show the signcolumn, otherwise it would shift the text each time
-- diagnostics appeared/became resolved
G.opt.signcolumn = "yes"

local keyset = vim.keymap.set
-- Autocomplete
function _G.check_back_leader()
    local col = G.fn.col('.') - 1
    return col == 0 or G.fn.getline('.'):sub(col, col):match('%s') ~= nil
end

-- Use Tab for trigger completion with characters ahead and navigate
-- NOTE: There's always a completion item selected by default, you may want to enable
-- no select by setting `"suggest.noselect": true` in your configuration file
-- NOTE: Use command ':verbose imap <tab>' to make sure Tab is not mapped by
-- other plugins before putting this into your config
local opts = {silent = true, noremap = true, expr = true, replace_keycodes = false}
keyset("i", "<TAB>", 'coc#pum#visible() ? coc#pum#next(1) : v:lua.check_back_leader() ? "<TAB>" : coc#refresh()', opts)
keyset("i", "<S-TAB>", [[coc#pum#visible() ? coc#pum#prev(1) : "\<C-h>"]], opts)

-- Make <CR> to accept selected completion item or notify coc.nvim to format
-- <C-g>u breaks current undo, please make your own choice
keyset("i", "<cr>", [[coc#pum#visible() ? coc#pum#confirm() : "\<C-g>u\<CR>\<c-r>=coc#on_enter()\<CR>"]], opts)

-- Use `[g` and `]g` to navigate diagnostics
-- Use `:CocDiagnostics` to get all diagnostics of current buffer in location list
keyset("n", "[g", "<Plug>(coc-diagnostic-prev)", {silent = true})
keyset("n", "]g", "<Plug>(coc-diagnostic-next)", {silent = true})

-- GoTo code navigation
keyset("n", "gd", "<Plug>(coc-definition)", {silent = true})
keyset("n", "gy", "<Plug>(coc-type-definition)", {silent = true})
keyset("n", "gi", "<Plug>(coc-implementation)", {silent = true})
keyset("n", "gr", "<Plug>(coc-references)", {silent = true})

-- Symbol renaming
keyset("n", "<leader>rn", "<Plug>(coc-rename)", {silent = true})

-- Formatting selected code
keyset("x", "<leader>i", "<Plug>(coc-format-selected)", {silent = true})
keyset("n", "<leader>i", "<Plug>(coc-format-selected)", {silent = true})

-- Apply codeAction to the selected region
-- Example: `<leader>aap` for current paragraph
local opts = {silent = true, nowait = true}

-- Map function and class text objects
-- NOTE: Requires 'textDocument.documentSymbol' support from the language server
keyset("x", "if", "<Plug>(coc-funcobj-i)", opts)
keyset("o", "if", "<Plug>(coc-funcobj-i)", opts)
keyset("x", "af", "<Plug>(coc-funcobj-a)", opts)
keyset("o", "af", "<Plug>(coc-funcobj-a)", opts)
keyset("x", "ic", "<Plug>(coc-classobj-i)", opts)
keyset("o", "ic", "<Plug>(coc-classobj-i)", opts)
keyset("x", "ac", "<Plug>(coc-classobj-a)", opts)
keyset("o", "ac", "<Plug>(coc-classobj-a)", opts)

-- explorer
keyset("n", "<c-e>", ":CocCommand explorer<CR>")
-- translator
keyset("n", "<leader>tt", "<Plug>(coc-translator-p)")
keyset("v", "<leader>tt", "<Plug>(coc-translator-pv)")
-- translator-releader
keyset("n", "<leader>tr", "<Plug>(coc-translator-r)")
keyset("v", "<leader>tr", "<Plug>(coc-translator-rv)")
keyset("n", "<leader>ol", ":CocOutline<CR>")