check_for_eslint_and_config_prettier

" returns 1 if:
"   eslintConfig exists in package.json and eslint is a devDependency
"   .eslintrc exists and eslint is a devDependency in package.json
" returns 0 if
"   eslint is a devDependency but no eslintConfig or .eslintrc is found,
"   this is because eslint does not turn on any validation rules by default
"   eslint is not a devDependency
function! HasEslint()
  "a: indicates that the variable is argument scoped
  "l: specifies that a variable is local to a function

  " system executes a command in the shell and returns the result as a string
  " has is a jq filter that returns true if an object has a key, if not it returns false
  let l:pkgJsonConf = system("jq < package.json 'has(\"eslintConfig\")'") =~# 'true'

  " ==# and !=# do a case sensitive string comparision
  let l:fileConf = findfile('.eslintrc', escape(expand('<amatch>:h'),' ') . ';') !=# ''

  let l:hasConfig =  l:pkgJsonConf || l:fileConf
  let l:hasDep = system("jq < package.json '.devDependencies | has(\"eslint\")'")

  " double quote does not work in the if statement below
  let l:res = l:hasConfig == 1 && l:hasDep =~# 'true'
  " echom l:res
  return l:res
endfunction

" neoformat should try formatprg where available
let g:neoformat_try_formatprg = 1
augroup vimrc
  " if eslint is found
  if HasEslint()
    "get path of prettier-eslint
    let g:prettier_eslint_path =  system('PATH=$(npm bin):$PATH && which prettier-eslint')
    let g:prettier_eslint_path2 = substitute(g:prettier_eslint_path,'[@\^\n\t\r]', '', 'g')
    echom g:prettier_eslint_path
    echom g:prettier_eslint_path2

    if s:has_eslintrc_path
      "get full path to eslintrc if eslintrc file exists
      let g:eslintrc_full_path = getcwd() + s:eslintrc_path
      echom g:eslintrc_full_path
      autocmd FileType javascript execute "setlocal formatprg=".g:prettier_eslint_path2."\\ --filePath\\ ".g:eslintrc_full_path
    elseif s:has_eslintConfig
      let g:eslintConfig = system("jq -cr < package.json '.eslintConfig'")
      let g:eslintEscapedConfig = substitute(g:eslintConfig, '[\n\t\r]\?', '', 'g')
      echom g:eslintConfig
      echom g:eslintEscapedConfig
      autocmd FileType javascript execute "setlocal formatprg=".g:prettier_eslint_path2."\\ --eslintConfig\\ ".g:eslintEscapedConfig
    endif
  else
    " just use prettier-standard
    autocmd FileType javascript set formatprg=prettier-standard
  endif
  autocmd BufWritePre *.js Neoformat
  " autocmd BufWritePre,TextChanged,InsertLeave *.js Neoformat
augroup end

" Merge commands into augroup vimrc
" augroup vimrc
  "checks for .eslintrc and  before falling back to standard
autocmd BufNewFile,BufReadPre *.js let b:syntastic_checkers = HasEslint() ? ['eslint'] : ['standard']

augroup end