# Tree-Sitter LAMMPS

A [tree-sitter](https://github.com/tree-sitter/tree-sitter) parser for input scripts for the [LAMMPS](https://github.com/lammps/lammps) molecular dynamics simulations package.

## Tree-sitter

### Grammar: `grammar.js`

This file contains code that is transpiled to the parser.
It is a DSL that is described in the [tree-sitter docs](https://tree-sitter.github.io/tree-sitter/creating-parsers)

### Queries `queries/*.scm`

These files describe how the tree should be read and allows for
syntax highlighting

## Using with Neovim

1.  Install [nvim-treesitter](https://github.com/nvim-treesitter/nvim-treesitter) plugin to  Neovim
2.  Add the following to your `init.lua` to define lammps file types:

    ``` lua
    -- LAMMPS File type
    vim.filetype.add {
    extension = {
    lmp = 'lammps',
      },

      pattern = {
        -- These are lua matching patterns, not regex
        ['.*%.lmp'] = 'lammps',
        ['in%..*'] = 'lammps',
        ['.*%.in'] = 'lammps',
      },
    }

    ```

4.  Add the following to your `init.lua` to tell tree-sitter how
    to access this parser:

    ``` lua

    local parser_config = require('nvim-treesitter.parsers').get_parser_configs()
    parser_config.lammps = {
      install_info = {
        url = 'https://github.com/chappertron/tree-sitter-lammps', -- local path or git repo
        files = { 'src/parser.c', 'src/scanner.c' }, -- note that some parsers also require src/scanner.c or src/scanner.cc
        -- optional entries:
        branch = 'main', -- default branch in case of git repo if different from master
        generate_requires_npm = false, -- if stand-alone parser without npm dependencies
        requires_generate_from_grammar = false, -- if folder contains pre-generated src/parser.c
      },
      filetype = 'lammps', -- if filetype does not match the parser name
    }

    vim.treesitter.language.register('lammps', 'lammps')

    ```

6.  run `:TSInstallFromGrammar lammps` to install the tree-sitter grammar.
7.  Copy the files from `queries` in this repo to a folder `queries/lammps`
    in the same directory as your `init.lua`
8.  Presto! Your LAMMPS input scripts should now have pretty
    colours