tree-sitter-leaf

A Tree-sitter grammar for the Leaf templating language used in Vapor (Swift).

Features

• Full support for Leaf directives (#extend, #export, #import, #if, #unless, #for, #while)
• Leaf variables with expression support (#(variable), #(user.name), #(count + 1))
• HTML parsing with proper nesting
• String interpolation and complex expressions
• Syntax highlighting, indentation, and language injections
• Comment support for Leaf (///), regular (//), and HTML (<!-- -->) comments
• Error handling and recovery for better editing experience

Installation

Neovim with nvim-treesitter

Add this to your Neovim configuration:

{
  'nvim-treesitter/nvim-treesitter',
  build = ':TSUpdate',
  config = function()
    -- Custom leaf parser
    local parser_config = require('nvim-treesitter.parsers').get_parser_configs()
    parser_config.leaf = {
      install_info = {
        url = 'https://github.com/visualbam/tree-sitter-leaf',
        files = { 'src/parser.c' },
        branch = 'master',
      },
      filetype = 'leaf',
    }

    -- Simple filetype detection for grep preview
    vim.filetype.add({ extension = { leaf = 'leaf' } })
    vim.treesitter.language.register('leaf', 'leaf')

    -- Configure comment strings for gcc motion
    vim.api.nvim_create_autocmd("FileType", {
      pattern = "leaf",
      callback = function()
          vim.bo.commentstring = "<!-- %s -->"
      end,
    })

    -- Standard setup
    require('nvim-treesitter.configs').setup {
      ensure_installed = {
        'bash', 'c', 'diff', 'html', 'lua', 'luadoc', 'markdown', 'markdown_inline',
        'query', 'vim', 'vimdoc', 'typescript', 'javascript', 'json', 'css', 'scss',
        'yaml', 'java', 'c_sharp', 'leaf',
      },
      auto_install = true,
      highlight = { enable = true },
      indent = { enable = true },
    }
  end,
}