Quickly create a scatch in Neovim

I missed the feature of quickly creating a scratch when I switched back to Vim from Webstorm.

A scratch file is handy, it auto-saves somewhere on your computer and allows you to paste temporary content here to do whatever you want.

In Vim or Neovim you need to open a new buffer with :new or :vnew , then :set filetype {sometype}. Paste the content, then :w to save it somewhere, you also need to name it, what a cumbersome process.

Say no more, this is my Neovim Lua script.

-- Require the fzf-lua plugin
local fzf_lua = require("fzf-lua")

-- Function to open a new scratch buffer with a specific filetype
local function open_scratch_buffer(filetype)
    -- Generate a timestamp for unique file naming
    local date_time = os.date("%Y-%m-%d_%H-%M-%S")
    -- Define the directory where scratch files will be stored
    local scratch_dir = vim.fn.expand("~/.vim/scratches/")
    -- Create the full path for the new scratch file
    local filename = scratch_dir .. date_time .. "." .. filetype

    -- Create the scratch directory if it does not exist
    vim.fn.mkdir(scratch_dir, "p")
    -- Open a new vertical split with the created file
    vim.cmd("vnew " .. vim.fn.fnameescape(filename))
    -- Set the filetype for the new buffer for appropriate syntax highlighting
    vim.api.nvim_buf_set_option(0, "filetype", filetype)
    -- Save the file to create it on disk
    vim.api.nvim_command("write")
end

-- Global function to select a filetype and create a scratch buffer
function _G.select_filetype_and_create_scratch()
    -- Retrieve the list of Vim syntax files from the runtime path
    local syntax_dir = vim.fn.globpath(vim.fn.getenv("VIMRUNTIME"), "syntax/*.vim", false, true)
    local filetypes = {}

    -- Extract filetype names from the retrieved syntax file paths
    for _, filepath in ipairs(syntax_dir) do
        local filetype = filepath:match("syntax[/\\](.+).vim$")
        if filetype then
            -- Add the filetype to the list
            table.insert(filetypes, filetype)
        end
    end

    -- Execute fzf with the list of filetypes
    fzf_lua.fzf_exec(filetypes, {
        prompt = "Filetypes> ",
        actions = {
            -- Action to perform when a filetype is selected
            ["default"] = function(selected)
                open_scratch_buffer(selected[1])
            end,
        },
    })
end

-- Set a key mapping for the function
-- <leader>t will trigger the filetype selection and scratch buffer creation
vim.api.nvim_set_keymap("n", "<leader>t", ":lua _G.select_filetype_and_create_scratch()<CR>", { noremap = true })

What does it do?

1. Get the list of vim supported file types, grep the base name only to make the list of available file types

2. Use fzf.lua API fzf_exec to serve the list, and provide you with a UI for fuzzy searching

3. Select the user's selected file type, open a new buffer to the right, name it the current datetime, and save it. Now you can paste your content here.

Why the auto-save part is important?

Because some commands like :EslintAutoFix won't run on an unsaved buffer.

To use this, you need:

1. You Neovim are using init.lua

2. You need to install fzf-lua. I tried with fzf.vim but no luck, incompatible.

3. Add this script to your init.lua file require("scratch_config") assumed you have this script name scratch_config

4. Benefit

For more information, check my latest update https://github.com/finnng/dotfiles/blob/master/nvim/lua/scratch_config.lua

This is my repo so it may change at any time, in that case you can visit the commit https://github.com/finnng/dotfiles/commit/c09b79cd455e940cdb07ad836bfce2ca255fd2de