vim ruby folding for methods

vim-ruby-folding-1.1.vim

" FoldSearch-based folding.
" Copyright (C) 2005 Mauricio Fernandez <mfp@acm.org>
" Current version: http://eigenclass.org/hiki.rb?Usable+Ruby+folding+for+Vim
"
" Add this to your .vimrc and fold with :R. The default fold expression will
" work with Ruby scripts; you can specify where folds start with
" let b:foldsearchexpr = 'myexpression'
" e.g.
"  let b:foldsearchexpr='\(^\s*\(\(private\|public\|protected\|class\)\s\)\)'
" or so for Java.
" One way to have this buffer-local variable set is
" au Filetype java let b:foldsearchexpr='\(^\s*\(\(private\|public\|protected\|class\)\s\)\)'
"
" It is possible to have comments above a method/class/etc be included in the
" fold, by setting b:foldsearchprefix. All the lines above the detected fold
" matching b:foldsearchprefix will be included in said fold.
" For instance, for Ruby code:
"   let b:foldsearchprefix = '\v^\s*(#.*)?$'
" which can be automated with
"   au Filetype ruby let b:foldsearchprefix='\v^\s*(#.*)?$'
"
" Changelog:
" 2005-12-12  1.1  use b:foldsearchprefix to prepend comments to a fold.

"{{{ set s:sid

map <SID>xx <SID>xx
let s:sid = maparg("<SID>xx")
unmap <SID>xx
let s:sid = substitute(s:sid, 'xx', '', '')

"{{{ FoldText
function! s:Num2S(num, len)
    let filler = "                                                            "
    let text = '' . a:num
    return strpart(filler, 1, a:len - strlen(text)) . text
endfunction

execute 'set foldtext=' .  s:sid . 'MyNewFoldText()'
function! <SID>MyNewFoldText()
	let linenum = v:foldstart
	while linenum <= v:foldend
	    let line = getline(linenum)
	    if !exists("b:foldsearchprefix") || match(line, b:foldsearchprefix) == -1
		break
	    else
		let linenum = linenum + 1
	    endif
	endwhile
	if exists("b:foldsearchprefix") && match(line, b:foldsearchprefix) != -1
	    " all lines matched the prefix regexp
	    let line = getline(v:foldstart)
	endif
	let sub = substitute(line, '/\*\|\*/\|{{{\d\=', '', 'g')
	let diff = v:foldend - v:foldstart + 1
	return  '+ [' . s:Num2S(diff,4) . ']' . sub
endfunction

"{{{~foldsearch adapted from t77: Fold on search result (Fs <pattern>)
"Fs pattern Fold search
"Vimtip put to good use by Ralph Amissah zxy@irc.freenode.net
"Modified by Mauricio Fernandez <mfp@acm.org>
function! Foldsearch(search)
	setlocal fdm=manual
	let origlineno = line(".")
	normal zE
	normal G$
	let folded = 0     "flag to set when a fold is found
	let flags = "w"    "allow wrapping in the search
	let line1 =  0     "set marker for beginning of fold
	if a:search == ""
	    if exists("b:foldsearchexpr")
		let searchre = b:foldsearchexpr
	    else
		"Default value, suitable for Ruby scripts
		"\(^\s*\(\(def\|class\|module\)\s\)\)\|^\s*[#%"0-9]\{0,4\}\s*{\({{\|!!\)
		let searchre = '\v(^\s*(def|class|module|attr_reader|attr_accessor|alias_method)\s' . 
		             \ '|^\s*\w+attr_(reader|accessor)\s|^\s*[#%"0-9]{0,4}\s*\{(\{\{|!!))' .
		             \ '|^\s*[A-Z]\w+\s*\='
		let b:foldsearchexpr = searchre
	    endif
	else
	    let searchre = a:search
	endif
	while search(searchre, flags) > 0
		let  line2 = line(".")
		while line2 - 1 >= line1 && line2 - 1 > 0 "sanity check
		   let prevline = getline(line2 - 1)
		   if exists("b:foldsearchprefix") && (match(prevline, b:foldsearchprefix) != -1)
		       let line2 = line2 - 1
		   else
		       break
		   endif
		endwhile
		if (line2 -1 >= line1)
			execute ":" . line1 . "," . (line2-1) . "fold"
			let folded = 1       "at least one fold has been found
		endif
		let line1 = line2     "update marker
		let flags = "W"       "turn off wrapping
	endwhile
	normal $G
	let  line2 = line(".")
	if (line2  >= line1 && folded == 1)
		execute ":". line1 . "," . line2 . "fold"
	endif
	execute "normal " . origlineno . "G"
endfunction

"{{{~folds Fold Patterns
" Command is executed as ':Fs pattern'"
command! -nargs=? -complete=command Fs call Foldsearch(<q-args>)
command! -nargs=? -complete=command Fold call Foldsearch(<q-args>)
command! R Fs \(^\s*\(\(def\|class\|module\)\s\)\)\|^\s*[#%"0-9]\{0,4\}\s*{\({{\|!!\)
"command! R Fs