Vim Gherkin Formatter

A small CLI to autoformat Gherkin feature files.

Prerequisites

In order to install and use the formatter, it is required to have NodeJS runtime environment installed.

Building the formatter

In order to build the formatter, follow these steps:

1. Clone the repo to your machine
2. Go into the repo directory and execute npm install
3. When the previou step finishes, execute npm run build
4. Install the formatter locally into the folder which exists in $PATH, e.g. to install into ~/.local/bin execute npm install -g ./ --prefix ~/.local

The last step will create symbolic links to the artifacts of the build step.

How to use

After installation one can simply call it as a CLI script

vim-gherkin-formatter my_file.feature

One can even specify a pattern to look for, e.g.

vim-gherkin-formatter *.feature

to format multiple files. This will overwrite the unformatted file(s) with their formatted version.

Autoformat in Vim/Neovim

Create a file: ~/.config/nvim/after/ftplugin/cucumber.vim with content

" Only do this when not done yet for this buffer
if exists("b:did_ft_cucumber_formatter")
  finish
endif
let b:did_ft_cucumber_formatter = 1

" Gherkin formatter
function s:DoFormatGherkin()
  let l:cur_buffer = bufnr('%')
  if getbufvar(l:cur_buffer, "&mod")
    let l:do_save = confirm("Must save the buffer first.", "&yes\n&no", 1)
    if l:do_save == 1
      write
    else
      return
    endif
  endif
  execute "!vim-gherkin-formatter %" | edit
endfunction

augroup GHERKIN
  " remove all existing listeners in this group before reattaching them
  autocmd!

  " Define commands and mappings local to the Gherkin files
  autocmd BufEnter *.feature command! GherkinFormat :silent call s:DoFormatGherkin()
  autocmd BufLeave *.feature delcommand GherkinFormat

  autocmd BufEnter *.feature nnoremap <buffer> <F4> :GherkinFormat<cr>

  " autocmd BufWritePost *.feature :GherkinFormat<cr>
augroup END

After this, reload Vim/Neovim so that changes are sourced. The above defines a :GherkinFormat command and a mapping to it, <F4>, which are available only when editing the *.feature Gherkin files.