Fix #252 improve optional placeholder behavior

autoload/neosnippet/mappings.vim

@@ -188,7 +188,7 @@ function! s:trigger(function) "{{{
   " Get selected text.
   let neosnippet = neosnippet#variables#current_neosnippet()
   let neosnippet.trigger = 1
-  if mode() ==# 's' && neosnippet.selected_text =~ '^#:'
+  if mode() ==# 's' && neosnippet.optional_tabstop
     let expr .= "\<C-o>\"_d"
   endif
 

autoload/neosnippet/variables.vim

@@ -33,6 +33,7 @@ function! neosnippet#variables#current_neosnippet() "{{{
           \ 'selected_text' : '',
           \ 'target' : '',
           \ 'trigger' : 0,
+          \ 'optional_tabstop' : 0,
           \}
   endif
 

autoload/neosnippet/view.vim

@@ -289,11 +289,15 @@ function! s:expand_placeholder(start, end, holder_cnt, line, ...) "{{{
   let default = substitute(
         \ matchstr(current_line, default_pattern),
         \ '\\\ze[^\\]', '', 'g')
+  let neosnippet.optional_tabstop = (default =~ '^#:')
   if !is_select && default =~ '^#:'
     " Delete comments.
     let default = ''
   endif
 
+  " Remove optional marker
+  let default = substitute(default, '^#:', '', '')
+
   let is_target = (default =~ '^TARGET\>' && neosnippet.target != '')
   let default = substitute(default, '^TARGET:\?', neosnippet.target, '')
 

doc/neosnippet.txt

@@ -453,7 +453,7 @@ available providing different functionality.
 
 The structure of a placeholder can be:
 
-- ${number:placeholder text}
+- ${number:default placeholder text}
 
 	The placeholder starts with a dollar sign "$". The number of a
 	placeholder and the placeholder text are separated by a colon ":".
@@ -472,7 +472,7 @@ The structure of a placeholder can be:
 	   endif
 <
 
-- ${number:#:placeholder text}
+- ${number:#:optional placeholder text}
 
 	In this kind of placeholder the number is followed by the hash
 	character "#".  If you jump over this placeholder and do not insert