Allow use of function references as callbacks (#1067)

* NERDTreeToggleVCS

* nerdtree toggle vcs documentation

* fix function documentation

* changelog

* Update CHANGELOG.md

* Update CHANGELOG.md

* simplify toggletreevcs

* Update CHANGELOG.md

.github/PULL_REQUEST_TEMPLATE.md

@@ -5,9 +5,12 @@ Closes #  <!-- Issue number this PR addresses. If none, remove this line. -->
 ---
 ### New Version Info
 
-- [ ] Derive a new version number. Increment the:
+#### Author's Instructions
-    - [ ] `MAJOR` version when you make incompatible API changes
+- [ ] Derive a new `MAJOR.MINOR.PATCH` version number. Increment the:
-    - [ ] `MINOR` version when you add functionality in a backwards-compatible manner
+    - `MAJOR` version when you make incompatible API changes
-    - [ ] `PATCH` version when you make backwards-compatible bug fixes
+    - `MINOR` version when you add functionality in a backwards-compatible manner
+    - `PATCH` version when you make backwards-compatible bug fixes
 - [ ] Update [CHANGELOG.md](https://github.com/scrooloose/nerdtree/blob/master/CHANGELOG.md), following the established pattern.
-- [ ] Tag the merge commit, e.g. `git tag -a 3.1.4 -m "v3.1.4" && git push origin --tags`
+#### Collaborator's Instructions
+- [ ] Review [CHANGELOG.md](https://github.com/scrooloose/nerdtree/blob/master/CHANGELOG.md), suggesting a different version number if necessary.
+- [ ] After merge, tag the merge commit, e.g. `git tag -a 3.1.4 -m "v3.1.4" && git push origin --tags`

CHANGELOG.md

@@ -1,18 +1,34 @@
-# Change Log
+# NERDTree Change Log
 
-#### 6.1...
+<!--
+    Introduce a new MAJOR.MINOR version with a 4-hash header.
+
+    PATCH versions are listed from newest to oldest under their respective MAJOR.MINOR version
+    in an unordered list.  The format is:
+        - **.PATCH**: Pull Request Title (PR Author) [PR Number](Link to PR)
+-->
+#### 6.4
+- **.0**: Allow use of function references as callbacks (HiPhish) [#1067](https://github.com/scrooloose/nerdtree/pull/1067)
+#### 6.3
+- **.0**: Add new command that behaves like NERDTreeToggle but defaults to the root of a VCS repository. (willfindlay) [#1060](https://github.com/scrooloose/nerdtree/pull/1060)
+#### 6.2
+- **.1**: Menu option, 'copy path to clipboard' is aware of VIM clipboard option (jhzn) [#1056](https://github.com/scrooloose/nerdtree/pull/1056)
+- **.0**: Support tab-specific CWDs (PhilRunninger) [#1032](https://github.com/scrooloose/nerdtree/pull/1032)
+#### 6.1
+- **.4**: Add VIM built-in package management to read me file. (pesarkhobeee) [#1049](https://github.com/scrooloose/nerdtree/pull/1049)
+- **.3**: Save/Set screen state also on WinLeave and WinEnter. (PhilRunninger) [#1048](https://github.com/scrooloose/nerdtree/pull/1048)
 - **.2**: Wrap saveScreenState's statements in a try-catch block. (PhilRunninger) [#1047](https://github.com/scrooloose/nerdtree/pull/1047)
 - **.1**: Catch errors when trying to read CHANGELOG.md. (PhilRunninger) [#1045](https://github.com/scrooloose/nerdtree/pull/1045)
 - **.0**: If file path doesn't exist, :NERDTreeFind its parent directory instead. (PhilRunninger) [#1043](https://github.com/scrooloose/nerdtree/pull/1043)
-#### 6.0...
+#### 6.0
 - **.1**: Reintroduce necessary variable mistakenly removed. (PhilRunninger) [#1040](https://github.com/scrooloose/nerdtree/pull/1040)
 - **.0**: Make the behavior of window splits consistent (dragonxlwang, PhilRunninger) [#1035](https://github.com/scrooloose/nerdtree/pull/1035)
-#### 5.3...
+#### 5.3
 - **.3**: Fix (p)ath not displaying in the minimal menu (tuzz) [#1038](https://github.com/scrooloose/nerdtree/pull/1038)
 - **.2**: Enable events when closing NerdTree window. (PhilRunninger) [#1037](https://github.com/scrooloose/nerdtree/pull/1037)
 - **.1**: Fix the `e` key mapping to use netrw if desired (PhilRunninger) [#1031](https://github.com/scrooloose/nerdtree/pull/1031)
 - **.0**: Add file extension and size to sorting capabilities (PhilRunninger) [#1029](https://github.com/scrooloose/nerdtree/pull/1029)
-#### 5.2...
+#### 5.2
 - **.9**: Suppress events for intermediate window/tab/buffer changes (PhilRunninger) [#1026](https://github.com/scrooloose/nerdtree/pull/1026)
 - **.8**: Revert [#1019](https://github.com/scrooloose/nerdtree/pull/1019) to fix nvim artifacts and flickering. (PhilRunninger) [#1021](https://github.com/scrooloose/nerdtree/pull/1021)
 - **.7**: Use :mode only in neovim. MacVim still needs to use :redraw! (PhilRunninger) [#1019](https://github.com/scrooloose/nerdtree/pull/1019)
@@ -23,7 +39,7 @@
 - **.2**: Make Enter work on the `.. ( up a dir )` line (PhilRunninger) [#1013](https://github.com/scrooloose/nerdtree/pull/1013)
 - **.1**: Fix nerdtree#version() on Windows. (PhilRunninger)
 - **.0**: Expand functionality of `<CR>` mapping. (PhilRunninger) [#1011](https://github.com/scrooloose/nerdtree/pull/1011)
-#### 5.1...
+#### 5.1
 - **.3**: Remove @mentions from PR template and change log. They weren't working. (PhilRunninger) [#1009](https://github.com/scrooloose/nerdtree/pull/1009)
 - **.2**: Fix NERDTree opening with the wrong size. (PhilRunninger) [#1008](https://github.com/scrooloose/nerdtree/pull/1008)
 - **.1**: Update Changelog and create PR Template (PhilRunninger) [#1007](https://github.com/scrooloose/nerdtree/pull/1007)

README.markdown

@@ -17,27 +17,62 @@ included documentation.
 Installation
 ------------
 
+Below are just some of the methods for installing NERDTree. Do not follow all of these instructions; just pick your favorite one. Other plugin managers exist, and NERDTree should install just fine with any of them.
+
+#### Vim 8+ packages
+
+If you are using VIM version 8 or higher you can use its built-in package management; see `:help packages` for more information. Just run these commands in your terminal:
+
+```bash
+git clone https://github.com/scrooloose/nerdtree.git ~/.vim/pack/vendor/start/nerdtree
+vim -u NONE -c "helptags ~/.vim/pack/vendor/start/nerdtree/doc" -c q
+```
+
+Otherwise, these are some of the several 3rd-party plugin managers you can choose from. Be sure you read the instructions for your chosen plugin, as there typically are additional steps you nee d to take.
+
 #### [pathogen.vim](https://github.com/tpope/vim-pathogen)
 
+In the terminal,
+```bash
 git clone https://github.com/scrooloose/nerdtree.git ~/.vim/bundle/nerdtree
+```
+In your vimrc,
+```vim
+call pathogen#infect()
+syntax on
+filetype plugin indent on
+```
 
-Then reload Vim, run `:helptags ~/.vim/bundle/nerdtree/doc/` or `:Helptags`, and check out `:help NERDTree.txt`.
+Then reload vim, run `:helptags ~/.vim/bundle/nerdtree/doc/` or `:Helptags`.
 
+#### [Vundle.vim](https://github.com/VundleVim/Vundle.vim)
+```vim
+call vundle#begin()
+Plugin 'scrooloose/nerdtree'
+call vundle#end()
+```
+
+#### [vim-plug](https://github.com/junegunn/vim-plug)
+```vim
+call plug#begin()
+Plug 'scrooloose/nerdtree'
+call plug#end()
+```
 
 #### [apt-vim](https://github.com/egalpin/apt-vim)
-
+```bash
 apt-vim install -y https://github.com/scrooloose/nerdtree.git
+```
 
-F.A.Q.
+F.A.Q. (here, and in the [Wiki](https://github.com/scrooloose/nerdtree/wiki))
 ------
 
-> Is there any support for `git` flags?
+#### Is there any support for `git` flags?
 
 Yes, install [nerdtree-git-plugin](https://github.com/Xuyuanp/nerdtree-git-plugin).
 
 ---
-
+#### Can I have the nerdtree on every tab automatically?
-> Can I have the nerdtree on every tab automatically?
 
 Nope. If this is something you want then chances are you aren't using tabs and
 buffers as they were intended to be used. Read this
@@ -46,53 +81,65 @@ http://stackoverflow.com/questions/102384/using-vims-tabs-like-buffers
 If you are interested in this behaviour then consider [vim-nerdtree-tabs](https://github.com/jistr/vim-nerdtree-tabs)
 
 ---
-> How can I open a NERDTree automatically when vim starts up?
+#### How can I open a NERDTree automatically when vim starts up?
 
 Stick this in your vimrc: `autocmd vimenter * NERDTree`
 
 ---
-> How can I open a NERDTree automatically when vim starts up if no files were specified?
+#### How can I open a NERDTree automatically when vim starts up if no files were specified?
 
 Stick this in your vimrc:
-
+```vim
 autocmd StdinReadPre * let s:std_in=1
 autocmd VimEnter * if argc() == 0 && !exists("s:std_in") | NERDTree | endif
+```
 
 Note: Now start vim with plain `vim`, not `vim .`
 
 ---
-> How can I open NERDTree automatically when vim starts up on opening a directory?
+#### What if I'm also opening a saved session, for example `vim -S session_file.vim`? I don't want NERDTree to open in that scenario.
+```vim
+autocmd StdinReadPre * let s:std_in=1
+autocmd VimEnter * if argc() == 0 && !exists("s:std_in") && v:this_session == "" | NERDTree | endif
+```
 
+---
+#### How can I open NERDTree automatically when vim starts up on opening a directory?
+```vim
 autocmd StdinReadPre * let s:std_in=1
 autocmd VimEnter * if argc() == 1 && isdirectory(argv()[0]) && !exists("s:std_in") | exe 'NERDTree' argv()[0] | wincmd p | ene | exe 'cd '.argv()[0] | endif
+```
 
 This window is tab-specific, meaning it's used by all windows in the tab. This trick also prevents NERDTree from hiding when first selecting a file.
 
 Note: Executing `vim ~/some-directory` will open NERDTree and a new edit window. `exe 'cd '.argv()[0]` sets the `pwd` of the new edit window to `~/some-directory`
 
 ---
-> How can I map a specific key or shortcut to open NERDTree?
+#### How can I map a specific key or shortcut to open NERDTree?
 
 Stick this in your vimrc to open NERDTree with `Ctrl+n` (you can set whatever key you want):
-
+```vim
 map <C-n> :NERDTreeToggle<CR>
+```
 
 ---
-> How can I close vim if the only window left open is a NERDTree?
+#### How can I close vim if the only window left open is a NERDTree?
 
 Stick this in your vimrc:
-
+```vim
 autocmd bufenter * if (winnr("$") == 1 && exists("b:NERDTree") && b:NERDTree.isTabTree()) | q | endif
+```
 
 ---
-> Can I have different highlighting for different file extensions?
+#### Can I have different highlighting for different file extensions?
 
 See here: https://github.com/scrooloose/nerdtree/issues/433#issuecomment-92590696
 
 ---
-> How can I change default arrows?
+#### How can I change default arrows?
 
 Use these variables in your vimrc. Note that below are default arrow symbols
-
+```vim
 let g:NERDTreeDirArrowExpandable = '▸'
 let g:NERDTreeDirArrowCollapsible = '▾'
+```

doc/NERDTree.txt

@@ -125,6 +125,14 @@ The following features and functionality are provided by the NERDTree:
     again.  If no NERDTree exists for this tab then this command acts the
     same as the |:NERDTree| command.
 
+:NERDTreeToggleVCS [<start-directory> | <bookmark>]            *:NERDTreeToggleVCS*
+    Like |:NERDTreeToggle|, but searches up the directory tree to find the top of
+    the version control system repository, and roots the NERDTree there. It
+    works with Git, Subversion, Mercurial, Bazaar, and Darcs repositories. A
+    couple of examples: >
+        :NERDTreeToggleVCS /home/marty/nerdtree/doc  (opens /home/marty/nerdtree)
+        :NERDTreeToggleVCS              (opens root of repository containing CWD)
+
 :NERDTreeFocus                                                  *:NERDTreeFocus*
     Opens (or reopens) the NERDTree if it is not currently visible;
     otherwise, the cursor is moved to the already-open NERDTree.
@@ -849,9 +857,17 @@ above nodes would then be sorted like this: >
     z110.txt
 <
 ------------------------------------------------------------------------------
-                                                             *NERDTreeChDirMode*
+                                                                *NERDTreeUseTCD*
+Values: 0 or 1.
+Default: 0.
 
-Values: 0, 1 or 2.
+By default, NERDTree will use the `:cd` command to change the current working
+directory. If this setting is turned on, and the `:tcd` command is available, it
+will be used instead.
+
+------------------------------------------------------------------------------
+                                                             *NERDTreeChDirMode*
+Values: 0, 1, 2, or 3.
 Default: 0.
 
 Use this setting to tell the script when (if at all) to change the current
@@ -871,6 +887,9 @@ the CWD is changed whenever the tree root is changed. For example, if the CWD
 is /home/marty/foobar and you make the node for /home/marty/foobar/baz the new
 root then the CWD will become /home/marty/foobar/baz.
 
+If the set to 3, then it behaves the same as if set to 2, and the CWD is
+changed whenever changing tabs to whatever the tree root is on that tab.
+
 ------------------------------------------------------------------------------
                                                    *NERDTreeHighlightCursorline*
 Values: 0 or 1.
@@ -980,7 +999,6 @@ then (to single click activate it) you must click somewhere in
 
 ------------------------------------------------------------------------------
                                                             *NERDTreeQuitOnOpen*
-
 Values: 0,1,2 or 3.
 Default: 0
 
@@ -1297,6 +1315,10 @@ following code conventions are used:
 See this blog post for more details:
  http://got-ravings.blogspot.com/2008/09/vim-pr0n-prototype-based-objects.html
 
+A number of API functions take a callback argument to call. The callback can
+be either a string with the name of a function to call, or a |Funcref| object
+which will be called directly.
+
 ------------------------------------------------------------------------------
 4.1. Key map API                                             *NERDTreeKeymapAPI*
 

lib/nerdtree/key_map.vim

@@ -66,7 +66,7 @@ endfunction
 "FUNCTION: KeyMap.invoke() {{{1
 "Call the KeyMaps callback function
 function! s:KeyMap.invoke(...)
-    let Callback = function(self.callback)
+    let Callback = type(self.callback) == v:t_func ? self.callback : function(self.callback)
     if a:0
         call Callback(a:1)
     else

lib/nerdtree/menu_item.vim

@@ -79,7 +79,7 @@ endfunction
 "specified
 function! s:MenuItem.enabled()
     if self.isActiveCallback != -1
-        return {self.isActiveCallback}()
+        return type(self.isActiveCallback) == v:t_func ? self.isActiveCallback() : {self.isActiveCallback}()
     endif
     return 1
 endfunction
@@ -94,9 +94,13 @@ function! s:MenuItem.execute()
         call mc.showMenu()
     else
         if self.callback != -1
+            if type(self.callback) == v:t_func
+                call self.callback()
+            else
                 call {self.callback}()
             endif
         endif
+    endif
 endfunction
 
 "FUNCTION: MenuItem.isSeparator() {{{1

lib/nerdtree/nerdtree.vim

@@ -20,7 +20,7 @@ function! s:NERDTree.changeRoot(node)
     call self.root.open()
 
     "change dir to the dir of the new root if instructed to
-    if g:NERDTreeChDirMode ==# 2
+    if g:NERDTreeChDirMode >= 2
         call self.root.path.changeToDir()
     endif
 

lib/nerdtree/notifier.vim

@@ -14,8 +14,9 @@ endfunction
 function! s:Notifier.NotifyListeners(event, path, nerdtree, params)
     let event = g:NERDTreeEvent.New(a:nerdtree, a:path, a:event, a:params)
 
-    for listener in s:Notifier.GetListenersForEvent(a:event)
+    for Listener in s:Notifier.GetListenersForEvent(a:event)
-        call {listener}(event)
+    	let Callback = type(Listener) == v:t_func ? Listener : function(Listener)
+        call Callback(event)
     endfor
 endfunction
 

lib/nerdtree/path.vim

@@ -87,8 +87,13 @@ function! s:Path.changeToDir()
     endif
 
     try
+        if g:NERDTreeUseTCD && exists(":tcd") == 2
+            execute "tcd " . dir
+            call nerdtree#echo("Tab's CWD is now: " . getcwd())
+        else
             execute "cd " . dir
             call nerdtree#echo("CWD is now: " . getcwd())
+        endif
     catch
         throw "NERDTree.PathChangeError: cannot change CWD to " . dir
     endtry
@@ -495,8 +500,9 @@ function! s:Path.ignore(nerdtree)
             endif
         endfor
 
-        for callback in g:NERDTree.PathFilters()
+        for Callback in g:NERDTree.PathFilters()
-            if {callback}({'path': self, 'nerdtree': a:nerdtree})
+            let Callback = type(Callback) == v:t_func ? Callback : function(Callback)
+            if Callback({'path': self, 'nerdtree': a:nerdtree})
                 return 1
             endif
         endfor

nerdtree_plugin/fs_menu.vim

@@ -369,7 +369,11 @@ endfunction
 function! NERDTreeCopyPath()
     let l:nodePath = g:NERDTreeFileNode.GetSelected().path.str()
     if has("clipboard")
+        if &clipboard == "unnamedplus"
+            let @+ = l:nodePath
+        else
             let @* = l:nodePath
+        endif
         call nerdtree#echo("The path [" . l:nodePath . "] was copied to your clipboard.")
     else
         call nerdtree#echo("The full path is: " . l:nodePath)

nerdtree_plugin/vcs.vim

@@ -11,6 +11,7 @@
 "
 " ============================================================================
 command! -n=? -complete=dir -bar NERDTreeVCS :call <SID>CreateTabTreeVCS('<args>')
+command! -n=? -complete=dir -bar NERDTreeToggleVCS :call <SID>ToggleTabTreeVCS('<args>')
 
 " FUNCTION: s:CreateTabTreeVCS(a:name) {{{1
 function! s:CreateTabTreeVCS(name)
@@ -19,6 +20,14 @@ function! s:CreateTabTreeVCS(name)
     call g:NERDTreeCreator.createTabTree(empty(l:path) ? "" : l:path._str())
 endfunction
 
+" FUNCTION: s:ToggleTabTreeVCS(a:name) {{{1
+" Behaves the same as ToggleTabTree except roots directory at VCS root
+function! s:ToggleTabTreeVCS(name)
+    let l:path = g:NERDTreeCreator._pathForString(a:name)
+    let l:path = s:FindParentVCSRoot(l:path)
+    call g:NERDTreeCreator.toggleTabTree(empty(l:path) ? "" : l:path._str())
+endfunction
+
 " FUNCTION: s:FindParentVCSRoot(a:path) {{{1
 " Finds the root version control system folder of the given path. If a:path is
 " not part of a repository, return the original path.

plugin/NERD_tree.vim

@@ -48,6 +48,7 @@ call s:initVariable("g:NERDTreeAutoCenterThreshold", 3)
 call s:initVariable("g:NERDTreeCaseSensitiveSort", 0)
 call s:initVariable("g:NERDTreeNaturalSort", 0)
 call s:initVariable("g:NERDTreeSortHiddenFirst", 1)
+call s:initVariable("g:NERDTreeUseTCD", 0)
 call s:initVariable("g:NERDTreeChDirMode", 0)
 call s:initVariable("g:NERDTreeCreatePrefix", "silent")
 call s:initVariable("g:NERDTreeMinimalUI", 0)
@@ -170,10 +171,10 @@ call nerdtree#ui_glue#setupCommands()
 "============================================================
 augroup NERDTree
     "Save the cursor position whenever we close the nerd tree
-    exec "autocmd BufLeave ". g:NERDTreeCreator.BufNamePrefix() ."* if g:NERDTree.IsOpen() | call b:NERDTree.ui.saveScreenState() | endif"
+    exec "autocmd BufLeave,WinLeave ". g:NERDTreeCreator.BufNamePrefix() ."* if g:NERDTree.IsOpen() | call b:NERDTree.ui.saveScreenState() | endif"
 
     "disallow insert mode in the NERDTree
-    exec "autocmd BufEnter ". g:NERDTreeCreator.BufNamePrefix() ."* stopinsert"
+    exec "autocmd BufEnter,WinEnter ". g:NERDTreeCreator.BufNamePrefix() ."* stopinsert"
 augroup END
 
 if g:NERDTreeHijackNetrw
@@ -183,6 +184,12 @@ if g:NERDTreeHijackNetrw
     augroup END
 endif
 
+if g:NERDTreeChDirMode == 3
+    augroup NERDTreeChDirOnTabSwitch
+        autocmd TabEnter * if g:NERDTree.ExistsForTab()|call g:NERDTree.ForCurrentTab().getRoot().path.changeToDir()|endif
+    augroup END
+endif
+
 " SECTION: Public API {{{1
 "============================================================
 function! NERDTreeAddMenuItem(options)