add some class methods to wrap the NERDTreeCreator public methods

This is needed because some versions of vim dont let you chain method
calls together. So do the work in NERDTreeCreator instead of forcing all
callers to break the New().createXXX() calls out onto 2 lines with an
intermediate variable.

Fixes #226.

plugin/NERD_tree.vim

@@ -149,11 +149,11 @@ runtime plugin/nerdtree/creator.vim
 " SECTION: Commands {{{1
 "============================================================
 "init the command that users start the nerd tree with
-command! -n=? -complete=dir -bar NERDTree :call g:NERDTreeCreator.New().createPrimary('<args>')
-command! -n=? -complete=dir -bar NERDTreeToggle :call g:NERDTreeCreator.New().togglePrimary('<args>')
+command! -n=? -complete=dir -bar NERDTree :call g:NERDTreeCreator.CreatePrimary('<args>')
+command! -n=? -complete=dir -bar NERDTreeToggle :call g:NERDTreeCreator.TogglePrimary('<args>')
 command! -n=0 -bar NERDTreeClose :call nerdtree#closeTreeIfOpen()
-command! -n=1 -complete=customlist,nerdtree#completeBookmarks -bar NERDTreeFromBookmark call g:NERDTreeCreator.New().createPrimary('<args>')
-command! -n=0 -bar NERDTreeMirror call g:NERDTreeCreator.New().createMirror()
+command! -n=1 -complete=customlist,nerdtree#completeBookmarks -bar NERDTreeFromBookmark call g:NERDTreeCreator.CreatePrimary('<args>')
+command! -n=0 -bar NERDTreeMirror call g:NERDTreeCreator.CreateMirror()
 command! -n=0 -bar NERDTreeFind call nerdtree#findAndRevealPath()
 command! -n=0 -bar NERDTreeFocus call NERDTreeFocus()
 command! -n=0 -bar NERDTreeCWD call NERDTreeCWD()
@@ -201,7 +201,7 @@ function! NERDTreeFocus()
     if nerdtree#isTreeOpen()
         call nerdtree#putCursorInTreeWin()
     else
-        call g:NERDTreeCreator.New().togglePrimary("")
+        call g:NERDTreeCreator.TogglePrimary("")
     endif
 endfunction
 

plugin/nerdtree/creator.vim

@@ -27,6 +27,12 @@ function! s:Creator._broadcastInitEvent()
     silent doautocmd User NERDTreeInit
 endfunction
 
+"FUNCTION: s:Creator.CreatePrimary(a:name) {{{1
+function! s:Creator.CreatePrimary(name)
+    let creator = s:Creator.New()
+    call creator.createPrimary(a:name)
+endfunction
+
 "FUNCTION: s:Creator.createPrimary(a:name) {{{1
 "name: the name of a bookmark or a directory
 function! s:Creator.createPrimary(name)
@@ -63,6 +69,12 @@ function! s:Creator.createPrimary(name)
     call self._broadcastInitEvent()
 endfunction
 
+"FUNCTION: s:Creator.CreateSecondary(dir) {{{1
+function! s:Creator.CreateSecondary(dir)
+    let creator = s:Creator.New()
+    call creator.createSecondary(a:dir)
+endfunction
+
 "FUNCTION: s:Creator.createSecondary(dir) {{{1
 function! s:Creator.createSecondary(dir)
     try
@@ -94,6 +106,12 @@ function! s:Creator.createSecondary(dir)
     call self._broadcastInitEvent()
 endfunction
 
+" FUNCTION: s:Creator.CreateMirror() {{{1
+function! s:Creator.CreateMirror()
+    let creator = s:Creator.New()
+    call creator.createMirror()
+endfunction
+
 " FUNCTION: s:Creator.createMirror() {{{1
 function! s:Creator.createMirror()
     "get the names off all the nerd tree buffers
@@ -248,6 +266,12 @@ function! s:Creator._setupStatusline()
     endif
 endfunction
 
+"FUNCTION: s:Creator.TogglePrimary(dir) {{{1
+function! s:Creator.TogglePrimary(dir)
+    let creator = s:Creator.New()
+    call creator.togglePrimary(a:dir)
+endfunction
+
 "FUNCTION: s:Creator.togglePrimary(dir) {{{1
 "Toggles the NERD tree. I.e the NERD tree is open, it is closed, if it is
 "closed it is restored or initialized (if it doesnt exist)

plugin/nerdtree/opener.vim

@@ -185,7 +185,7 @@ endfunction
 function! s:Opener._openDirectory(node)
     if self._treetype ==# "secondary"
         call self._gotoTargetWin()
-        call g:NERDTreeCreator.New().createSecondary(a:node.path.str())
+        call g:NERDTreeCreator.CreateSecondary(a:node.path.str())
     else
         call self._gotoTargetWin()
         if empty(self._where)
@@ -193,9 +193,9 @@ function! s:Opener._openDirectory(node)
             call nerdtree#renderView()
             call a:node.putCursorHere(0, 0)
         elseif self._where == 't'
-            call g:NERDTreeCreator.New().createPrimary(a:node.path.str())
+            call g:NERDTreeCreator.CreatePrimary(a:node.path.str())
         else
-            call g:NERDTreeCreator.New().createSecondary(a:node.path.str())
+            call g:NERDTreeCreator.CreateSecondary(a:node.path.str())
         endif
     endif
 

plugin/nerdtree/tree_dir_node.vim

@@ -351,7 +351,7 @@ endfunction
 "FUNCTION: TreeDirNode._openInNewTab() {{{1
 function! s:TreeDirNode._openInNewTab()
     tabnew
-    call g:NERDTreeCreator.New().createPrimary(self.path.str())
+    call g:NERDTreeCreator.CreatePrimary(self.path.str())
 endfunction
 
 "FUNCTION: TreeDirNode.openRecursively() {{{1