nlua

Lua script that let's you use Neovim as a Lua interpreter.

Neovim embeds a Lua interpreter, but it doesn't expose the same command line interface as plain lua.

The plain interface looks like this:

usage: lua [options] [script [args]]
Available options are:
  -e stat   execute string 'stat'
  -i        enter interactive mode after executing 'script'
  -l mod    require library 'mod' into global 'mod'
  -l g=mod  require library 'mod' into global 'g'
  -v        show version information
  -E        ignore environment variables
  -W        turn warnings on
  --        stop handling options
  -         stop handling options and execute stdin

nlua is a script which emulates that interface, Using Neovim's -l option under the hood.

Currently supported:

-e
-v
--
[script [args]]
stdin handling

Motivation

It let's you use Neovim as Lua interpreter for luarocks. This in turn allows you to run tools like busted to test Neovim plugins.
It allows tools like local-lua-debugger-vscode to use the Neovim Lua. Enabling debugging of busted test cases for Neovim plugins.

See:

Requirements

env executable supporting the -S option. Run env --help in a shell to verify.
Neovim 0.9+ with LuaJIT

Installation

This package is available on luarocks.

Install luarocks using a package manager. For example pacman -S luarocks
Install nlua via luarocks:
```
luarocks --local install nlua
```
Add ~/.luarocks/bin/nlua to your $PATH:
```
export PATH=$PATH:$HOME/.luarocks/bin:
```
Confirm it is working:
```
echo "print(1 + 2)" | nlua
```

Usage

Busted

luarocks --local install busted
busted --lua nlua spec/mytest_spec.lua

If you see a module 'busted.runner' not found error you need to update your LUA_PATH:

eval $(luarocks path --no-bin)
busted --lua nlua spec/mytest_spec.lua

CI for Neovim Plugins

You can use the plugin template to create a new repository that contains nlua/busted based test setup.

As Lua interpreter for luarocks

This allows package installation directly via nlua instead of a system lua

Create a ~/.luarocks/config-nlua.lua with the following contents.

For luarocks 3.10.0 and above:

lua_version = "5.1"
variables = {
   LUA = "$HOME/.luarocks/bin/nlua" -- path to where nlua is installed
   LUA_INCDIR = "/usr/include/luajit-2.1",
}

For luarocks 3.9.2 and below:

lua_version = "5.1"
variables = {
   lua_interpreter = "nlua"
   LUA_INCDIR = "/usr/include/luajit-2.1",
   LUA_BINDIR = "$HOME/.luarocks/bin", -- path to where nlua is installed
}

To make using this custom configuration a bit easier, you can create a small wrapper. Create a file called nluarocks somewhere in $PATH - e.g. in ~/.local/bin/nluarocks - with the following content:

#!/usr/bin/env bash

LUAROCKS_CONFIG=$HOME/.luarocks/config-nlua.lua luarocks --local "$@"

Now you should be able to install packages from luarocks using the nvim Lua-interpreter. For example:

nluarocks install busted

mfussenegger/nlua