[vim] Add 'sinklist' as a synonym to 'sink*'

So that it's easier to add a sinklist function to a spec dictionary.

  let spec = { 'source': source, 'options': ['--preview', preview] }
  function spec.sinklist(matches)
    echom string(a:matches)
  endfunction

  call fzf#run(fzf#wrap(spec))

README-VIM.md

@@ -283,7 +283,7 @@ The following table summarizes the available options.
 | `source`                   | list          | Vim list as input to fzf                                              |
 | `sink`                     | string        | Vim command to handle the selected item (e.g. `e`, `tabe`)            |
 | `sink`                     | funcref       | Reference to function to process each selected item                   |
-| `sink*`                    | funcref       | Similar to `sink`, but takes the list of output lines at once         |
+| `sinklist` (or `sink*`)    | funcref       | Similar to `sink`, but takes the list of output lines at once         |
 | `options`                  | string/list   | Options to fzf                                                        |
 | `dir`                      | string        | Working directory                                                     |
 | `up`/`down`/`left`/`right` | number/string | (Layout) Window position and size (e.g. `20`, `50%`)                  |
@@ -387,7 +387,7 @@ command! -bang -complete=dir -nargs=? LS
 
 - `g:fzf_layout`
 - `g:fzf_action`
-    - **Works only when no custom `sink` (or `sink*`) is provided**
+    - **Works only when no custom `sink` (or `sinklist`) is provided**
         - Having custom sink usually means that each entry is not an ordinary
           file path (e.g. name of color scheme), so we can't blindly apply the
           same strategy (i.e. `tabedit some-color-scheme` doesn't make sense)

doc/fzf.txt

@@ -300,7 +300,7 @@ The following table summarizes the available options.
   `source`                    | list          | Vim list as input to fzf
   `sink`                      | string        | Vim command to handle the selected item (e.g.  `e` ,  `tabe` )
   `sink`                      | funcref       | Reference to function to process each selected item
-  `sink*`                     | funcref       | Similar to  `sink` , but takes the list of output lines at once
+  `sinklist`  (or  `sink*` )    | funcref       | Similar to  `sink` , but takes the list of output lines at once
   `options`                   | string/list   | Options to fzf
   `dir`                       | string        | Working directory
   `up` / `down` / `left` / `right`  | number/string | (Layout) Window position and size (e.g.  `20` ,  `50%` )

plugin/fzf.vim

@@ -419,13 +419,13 @@ function! fzf#wrap(...)
   endif
 
   " Action: g:fzf_action
-  if !s:has_any(opts, ['sink', 'sink*'])
+  if !s:has_any(opts, ['sink', 'sinklist', 'sink*'])
     let opts._action = get(g:, 'fzf_action', s:default_action)
     let opts.options .= ' --expect='.join(keys(opts._action), ',')
-    function! opts.sink(lines) abort
+    function! opts.sinklist(lines) abort
       return s:common_sink(self._action, a:lines)
     endfunction
-    let opts['sink*'] = remove(opts, 'sink')
+    let opts['sink*'] = opts.sinklist " For backward compatibility
   endif
 
   return opts
@@ -943,6 +943,8 @@ function! s:callback(dict, lines) abort
     endif
     if has_key(a:dict, 'sink*')
       call a:dict['sink*'](a:lines)
+    elseif has_key(a:dict, 'sinklist')
+      call a:dict['sinklist'](a:lines)
     endif
   catch
     if stridx(v:exception, ':E325:') < 0