canter.nvim

Introduction

lightweight neovim code runner plugin that works with Snacks.nvim terminal

Demo

Table of Contents

• canter.nvim
  • Introduction
    • Demo
  • Table of Contents
  • Requirements
    • Optional (but recommended)
  • Installation
    • With lazy.nvim
    • Other package managers
  • Configuration
    • Options
      • Default options
      • Example config
  • Usage
    • Terminal Usage
    • Shebang example with node
    • Default Keybinds
  • Roadmap
  • Credits

Requirements

• Neovim (>= 0.7)

Optional (but recommended)

• Snacks.nvim (>= 2.11.0)
  • better Terminal
• which-key (>= 3.15.0)
  • custom leader key menu group name
• These both come default with lazy.nvim

Installation

With lazy.nvim

{
   "dchae/canter.nvim",
   opts = {}
},

Other package managers

Install normally, and add this line to your init.lua:

require("canter.nvim").setup()

Configuration

Pass your config table into the setup() function or opts if you use lazy.nvim.

Options

Default options

opts = {
  debug = false,
  -- File extension to runner/interpreter mapping
  runners = {},

  -- Terminal configuration
  terminal = {
    type = "snacks", -- "snacks" or "builtin"

    -- Options for built-in terminal
    builtin_opts = {
      position = "vsplit", -- "vsplit", "split", or "float"
      escape_keymap = true, -- escape terminal mode with <Esc>
    },

    -- Options for Snacks.nvim terminal
    snacks_opts = {
      win = {
        position = "bottom",
        relative = "editor",
      },
      interactive = false,
    },
  },

  -- Default keymaps (can be overridden)
  keymaps = {
    ["<leader><cr><cr>"] = {
      cmd = ":CanterRun<CR>",
      desc = "Run current file (Auto)",
    },
    ["<leader><cr>w"] = {
      cmd = ":CanterWait<CR>",
      desc = "Run current file (Wait)",
    },
  },
}

NOTE - does not come with runners by default, you must add your own.

• runners: table ([file_extension] = runner/interpreter)
• terminal: table of options passed to terminal
  • type: type of terminal
  • builtin_opts: options for built-in terminal
  • snacks_opts: options for Snacks.nvim terminal
• keymaps: table of keybindings and their descriptions

Example config

opts = {
  runners = {
    ["js"] = "node",
    ["rb"] = "ruby",
    ["py"] = "python"
  },
}

Usage

"Run current file (Auto)"

• if file contains a shebang on the first line, the plugin will attempt to:
  1. make the file executable via chmod
  2. execute the current file
• else, if the file has a corresponding runner
  1. execute the current file via its runner in Snacks.terminal

"Run current file (Wait)"

• same as above, but stops before actually executing so you can add flags or confirm the command before pressing enter.
  • necessarily, the terminal is interactive by default in this mode.

Terminal Usage

When using the built-in terminal in wait mode:

• Press <Esc> to exit terminal mode and return to normal mode (if escape_keymap is enabled)
• Alternatively, use the default Neovim terminal escape sequence: <C-\><C-n>

Shebang example with node

test.js

#!/usr/bin/env node

console.log("Hello, world!");
// "Hello, world!"

Default Keybinds

All keybinds can be customized in the config. The defaults are:

• <Leader><CR><CR>: Run current file (Auto)
  • executes current file in terminal
  • default behaviour is non-interactive; file will run and then any key will dismiss terminal
• <Leader><CR>w: Run current file (Wait)
  • loads current file run command in terminal
  • default behaviour is interactive

To customize keybinds, modify the keymaps table in your config:

opts = {
    keymaps = {
        -- Override default run binding
        ["<leader>r"] = {
            cmd = ":CanterRun<CR>",
            desc = "Run current file"
        },
        -- Add new binding
        ["<leader>rw"] = {
            cmd = ":CanterWait<CR>",
            desc = "Run and wait"
        }
    }
}

Roadmap

• should work with native terminal when Snacks is not available
• option to autosave before running
• refactor terminal code to a separate module
• automatically scan and resolve runners for a given file extension
  • prompt to set or confirm runner when new filetype is encountered
• native support for runner flags
• better compiled language support
  • should be able to compile, show build result, and run with one command
• native command to toggle or undo chmod make executable

Credits

• this plugin grew out of the custom keymap script I was using, which was in turn inspired by u/linkarzu script on r/neovim