coffescript custom folding

For "standard" JavaScript, I have this custom folding function which I like a lot:

function! JavaScriptFold()
    setl foldmethod=syntax
    setl foldlevelstart=1
    set fillchars=fold:\ 
    syn region foldBraces start=/{/ end=/}/ transparent fold keepend extend

    function! FoldText()
        return substitute(getline(v:foldstart), '{.*', '{...}', '')
    endfunction
    setl foldtext=FoldText()
endfunction

Could a kind soul please show me a translation of this for CoffeeScript? So that

testFunction = (x) -&g开发者_运维技巧t;
    x + x

would be folded like this into its first line only

testFunction = (x) ->

Bonus points for folding literal objects too, but functions would be great already!

PS: of course, I'm using the coffee-script plugin for Vim

As I don't know cofee, and I don't know what literal objects it support, I can't help with that. However what you want, can be achieved by this setting (which could be translated into a modeline):

:setl fdm=expr fde=getline(v:lnum)=~'->$'?'>1':getline(v:lnum)=~'^\\s*$'?0:'='

You didn't specify what to display on the fold, so I left this out. You can use the foldtext setting for that. See :h fold-foldtext for that.