Add :SignifyFold!

Closes #170.

autoload/sy/fold.vim

@@ -31,21 +31,62 @@ function! SignifyFoldText()
   return left . fill . right
 endfunction
 
-" Function: #do {{{1
-function! sy#fold#do() abort
+" Function: #dispatch {{{1
+function! sy#fold#dispatch(do_tab) abort
+  if a:do_tab
+    call sy#fold#enable(1)
+  else
+    call sy#fold#toggle()
+  endif
+endfunction
+
+" Function: #enable {{{1
+function! sy#fold#enable(do_tab) abort
   if !exists('b:sy')
     echomsg 'signify: I cannot detect any changes!'
     return
   endif
 
-  tabedit %
+  if a:do_tab
+    tabedit %
+  endif
+
   let [s:context0, s:context1] = get(g:, 'signify_fold_context', [3, 8])
   let s:levels = s:get_levels(s:get_lines())
 
-  set foldexpr=SignifyFoldExpr(v:lnum)
-  set foldtext=SignifyFoldText()
-  set foldmethod=expr
-  set foldlevel=0
+  setlocal foldexpr=SignifyFoldExpr(v:lnum)
+  setlocal foldtext=SignifyFoldText()
+  setlocal foldmethod=expr
+  setlocal foldlevel=0
+endfunction
+
+" Function: #disable {{{1
+function! sy#fold#disable() abort
+  let &l:foldmethod = w:sy_folded.method
+  let &l:foldtext = w:sy_folded.text
+  normal! zv
+endfunction
+
+" Function: #toggle {{{1
+function! sy#fold#toggle() abort
+  if exists('w:sy_folded')
+    call sy#fold#disable()
+    if w:sy_folded.method == 'manual'
+      loadview
+    endif
+    unlet w:sy_folded
+  else
+    let w:sy_folded = { 'method': &foldmethod, 'text': &foldtext }
+    if &foldmethod == 'manual'
+      let old_vop = &viewoptions
+      mkview
+      let &viewoptions = old_vop
+    endif
+    call sy#fold#enable(0)
+  endif
+
+  redraw!
+  call sy#start()
 endfunction
 
 " Function: s:get_lines {{{1
@@ -64,6 +105,7 @@ function! s:get_lines() abort
 
   return reverse(lines)
 endfunction
+" }}}
 
 " Function: s:get_levels {{{1
 function! s:get_levels(lines) abort

doc/signify.txt

@@ -323,6 +323,14 @@ Toggle the plugin for the current buffer only.
 <
 Toggle line highlighting for lines containing changes.
 
+------------------------------------------------------------------------------
+                                               *signify-:SignifyToggleFold*
+>
+    :SignifyToggleFold
+<
+Toggle folding for lines without changes. Using <bang> does on current buffer,
+without it on new tab.
+
 ------------------------------------------------------------------------------
                                                        *signify-:SignifyRefresh*
 >
@@ -333,7 +341,7 @@ Refresh signs in all windows.
 ------------------------------------------------------------------------------
                                                           *signify-:SignifyFold*
 >
-    :SignifyFold
+    :SignifyFold[!]
 <
 Open the current buffer in a new tabpage and set |'foldexpr'| so that only
 changed lines with their surrounding context are unfolded.
@@ -344,6 +352,9 @@ The |foldtext| will be set so that the left side shows the first line in the
 fold and the right side shows something like "50 [1]" which whereas "50"
 stands for the number of folded lines and the "1" is the foldlevel.
 
+If [!] is given, Sy will do the same without opening an extra tabpage. Another
+":SignifyFold!" will toggle back to the previous settings.
+
 See |folds| to learn more about folding.
 
 ------------------------------------------------------------------------------

plugin/signify.vim

@@ -38,13 +38,13 @@ augroup END
 
 " Init: commands {{{1
 
-command! -nargs=0 -bar SignifyDebug           call sy#debug#list_active_buffers()
-command! -nargs=0 -bar SignifyDebugDiff       call sy#debug#verbose_diff_cmd()
-command! -nargs=0 -bar SignifyDebugUnknown    call sy#repo#debug_detection()
-command! -nargs=0 -bar SignifyFold            call sy#fold#do()
-command! -nargs=0 -bar SignifyRefresh         call sy#util#refresh_windows()
-command! -nargs=0 -bar SignifyToggle          call sy#toggle()
-command! -nargs=0 -bar SignifyToggleHighlight call sy#highlight#line_toggle()
+command! -nargs=0 -bar       SignifyDebug           call sy#debug#list_active_buffers()
+command! -nargs=0 -bar       SignifyDebugDiff       call sy#debug#verbose_diff_cmd()
+command! -nargs=0 -bar       SignifyDebugUnknown    call sy#repo#debug_detection()
+command! -nargs=0 -bar -bang SignifyFold            call sy#fold#dispatch(<bang>1)
+command! -nargs=0 -bar       SignifyRefresh         call sy#util#refresh_windows()
+command! -nargs=0 -bar       SignifyToggle          call sy#toggle()
+command! -nargs=0 -bar       SignifyToggleHighlight call sy#highlight#line_toggle()
 
 " Init: mappings {{{1