Add VIM built-in package management to readme (#1049)

* Save/Set screen state also on WinLeave and WinEnter.

The particular use case here is when switching tabs with `gt` and the
NERDTrees have been mirrored.

* Update version number and change log.

.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

@@ -1,22 +1,39 @@
-# Change Log
+# NERDTree Change Log
 
-#### 5.3...
+<!--
-- **.3**: Fix (p)ath not displaying in the minimal menu [#1038](https://github.com/scrooloose/nerdtree/pull/1038)
+    Introduce a new MAJOR.MINOR version with a 4-hash header.
-- **.2**: Enable events when closing NerdTree window. [#1037](https://github.com/scrooloose/nerdtree/pull/1037)
+
-- **.1**: Fix the `e` key mapping to use netrw if desired [#1031](https://github.com/scrooloose/nerdtree/pull/1031)
+    PATCH versions are listed from newest to oldest under their respective MAJOR.MINOR version
-- **.0**: Add file extension and size to sorting capabilities [#1029](https://github.com/scrooloose/nerdtree/pull/1029)
+    in an unordered list.  The format is:
-#### 5.2...
+        - **.PATCH**: Pull Request Title (PR Author) [PR Number](Link to PR)
-- **.9**: Suppress events for intermediate window/tab/buffer changes [#1026](https://github.com/scrooloose/nerdtree/pull/1026)
+-->
+
+#### 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
+- **.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
+- **.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
+- **.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! [#1019](https://github.com/scrooloose/nerdtree/pull/1019)
+- **.7**: Use :mode only in neovim. MacVim still needs to use :redraw! (PhilRunninger) [#1019](https://github.com/scrooloose/nerdtree/pull/1019)
-- **.6**: In CHANGELOG.md and PR template, make reference to PR a true HTML link. [#1017](https://github.com/scrooloose/nerdtree/pull/1017)
+- **.6**: In CHANGELOG.md and PR template, make reference to PR a true HTML link. (PhilRunninger) [#1017](https://github.com/scrooloose/nerdtree/pull/1017)
 - **.5**: Use `:mode` instead of `:redraw!` when updating menu. (PhilRunninger) [#1016](https://github.com/scrooloose/nerdtree/pull/1016)
 - **.4**: When searching for root line num, stop at end of file. (PhilRunninger) [#1015](https://github.com/scrooloose/nerdtree/pull/1015)
 - **.3**: Fix `<CR>` key map on the bookmark (lkebin) [#1014](https://github.com/scrooloose/nerdtree/pull/1014)
 - **.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

@@ -17,6 +17,13 @@ included documentation.
 Installation
 ------------
 
+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:
+
+    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 other options:
+
 #### [pathogen.vim](https://github.com/tpope/vim-pathogen)
 
     git clone https://github.com/scrooloose/nerdtree.git ~/.vim/bundle/nerdtree

autoload/nerdtree.vim

@@ -4,24 +4,33 @@ endif
 let g:loaded_nerdtree_autoload = 1
 
 let s:rootNERDTreePath = resolve(expand("<sfile>:p:h:h"))
+
+"FUNCTION: nerdtree#version(...) {{{1
+"  If any value is given as an argument, the entire line of text from the
+"  change log is shown for the current version; otherwise, only the version
+"  number is shown.
 function! nerdtree#version(...)
-    let l:changelog = readfile(join([s:rootNERDTreePath, "CHANGELOG.md"], nerdtree#slash()))
     let l:text = 'Unknown'
-    let l:line = 0
+    try
-    while l:line <= len(l:changelog)
+        let l:changelog = readfile(join([s:rootNERDTreePath, "CHANGELOG.md"], nerdtree#slash()))
-        if l:changelog[l:line] =~ '\d\+\.\d\+'
+        let l:line = 0
-            let l:text = substitute(l:changelog[l:line], '.*\(\d\+.\d\+\).*', '\1', '')
+        while l:line <= len(l:changelog)
-            let l:text .= substitute(l:changelog[l:line+1], '^.\{-}\(\.\d\+\).\{-}:\(.*\)', a:0>0 ? '\1:\2' : '\1', '')
+            if l:changelog[l:line] =~ '\d\+\.\d\+'
-            break
+                let l:text = substitute(l:changelog[l:line], '.*\(\d\+.\d\+\).*', '\1', '')
-        endif
+                let l:text .= substitute(l:changelog[l:line+1], '^.\{-}\(\.\d\+\).\{-}:\(.*\)', a:0>0 ? '\1:\2' : '\1', '')
-        let l:line += 1
+                break
-    endwhile
+            endif
+            let l:line += 1
+        endwhile
+    catch
+    endtry
     return l:text
 endfunction
 
 " SECTION: General Functions {{{1
 "============================================================
 
+"FUNCTION: nerdtree#slash() {{{2
 function! nerdtree#slash()
 
     if nerdtree#runningWindows()
@@ -49,7 +58,6 @@ function! nerdtree#and(x,y)
             if (l:x % 2) && (l:y % 2)
                 let l:result += float2nr(pow(2, l:n))
             endif
-            echomsg l:x . ", " . l:y . " => " l:result
             let l:x = float2nr(l:x / 2)
             let l:y = float2nr(l:y / 2)
             let l:n += 1

autoload/nerdtree/ui_glue.vim

@@ -284,6 +284,9 @@ endfunction
 " FUNCTION: s:findAndRevealPath(pathStr) {{{1
 function! s:findAndRevealPath(pathStr)
     let l:pathStr = !empty(a:pathStr) ? a:pathStr : expand('%:p')
+    if !filereadable(l:pathStr)
+        let l:pathStr = fnamemodify(l:pathStr, ':h')
+    endif
 
     if empty(l:pathStr)
         call nerdtree#echoWarning('no file for the current buffer')

lib/nerdtree/nerdtree.vim

@@ -148,12 +148,19 @@ function! s:NERDTree.GetWinNum()
         return bufwinnr(t:NERDTreeBufName)
     endif
 
+    " If WindowTree, there is no t:NERDTreeBufName variable. Search all windows.
+    for w in range(1,winnr('$'))
+        if bufname(winbufnr(w)) =~# '^' . g:NERDTreeCreator.BufNamePrefix() . '\d\+$'
+            return w
+        endif
+    endfor
+
     return -1
 endfunction
 
 "FUNCTION: s:NERDTree.IsOpen() {{{1
 function! s:NERDTree.IsOpen()
-    return s:NERDTree.GetWinNum() != -1 || bufname('%') =~# '^' . g:NERDTreeCreator.BufNamePrefix() . '\d\+$'
+    return s:NERDTree.GetWinNum() != -1
 endfunction
 
 "FUNCTION: s:NERDTree.isTabTree() {{{1

lib/nerdtree/opener.vim

@@ -71,9 +71,9 @@ endfunction
 function! s:Opener._gotoTargetWin()
     if b:NERDTree.isWinTree()
         if self._where == 'v'
-            vsplit
+            call self._newVSplit()
         elseif self._where == 'h'
-            split
+            call self._newSplit()
         elseif self._where == 't'
             tabnew
         endif
@@ -153,44 +153,18 @@ endfunction
 
 " FUNCTION: Opener._newSplit() {{{1
 function! s:Opener._newSplit()
-    " Save the user's settings for splitbelow and splitright
-    let savesplitbelow=&splitbelow
-    let savesplitright=&splitright
-
-    " 'there' will be set to a command to move from the split window
-    " back to the explorer window
-    "
-    " 'back' will be set to a command to move from the explorer window
-    " back to the newly split window
-    "
-    " 'right' and 'below' will be set to the settings needed for
-    " splitbelow and splitright IF the explorer is the only window.
-    "
-    let there= g:NERDTreeWinPos ==# "left" ? "wincmd h" : "wincmd l"
-    let back = g:NERDTreeWinPos ==# "left" ? "wincmd l" : "wincmd h"
-    let right= g:NERDTreeWinPos ==# "left"
-    let below=0
-
-    " Attempt to go to adjacent window
-    call nerdtree#exec(back, 1)
-
     let onlyOneWin = (winnr("$") ==# 1)
-
+    let savesplitright = &splitright
-    " If no adjacent window, set splitright and splitbelow appropriately
     if onlyOneWin
-        let &splitright=right
+        let &splitright = (g:NERDTreeWinPos ==# "left")
-        let &splitbelow=below
-    else
-        " found adjacent window - invert split direction
-        let &splitright=!right
-        let &splitbelow=!below
     endif
-
+    " If only one window (ie. NERDTree), split vertically instead.
     let splitMode = onlyOneWin ? "vertical" : ""
 
     " Open the new window
     try
-        exec(splitMode." sp ")
+        call nerdtree#exec('wincmd p', 1)
+        call nerdtree#exec(splitMode . " split",1)
     catch /^Vim\%((\a\+)\)\=:E37/
         call g:NERDTree.CursorToTreeWin()
         throw "NERDTree.FileAlreadyOpenAndModifiedError: ". self._path.str() ." is already open and modified."
@@ -200,14 +174,12 @@ function! s:Opener._newSplit()
 
     "resize the tree window if no other window was open before
     if onlyOneWin
-        let size = exists("b:NERDTreeOldWindowSize") ? b:NERDTreeOldWindowSize : g:NERDTreeWinSize
+        let size = exists('b:NERDTreeOldWindowSize') ? b:NERDTreeOldWindowSize : g:NERDTreeWinSize
-        call nerdtree#exec(there, 1)
+        call nerdtree#exec('wincmd p', 1)
-        exec("silent ". splitMode ." resize ". size)
+        call nerdtree#exec('silent '. splitMode .' resize '. size, 1)
         call nerdtree#exec('wincmd p', 0)
     endif
 
-    " Restore splitmode settings
-    let &splitbelow=savesplitbelow
     let &splitright=savesplitright
 endfunction
 
@@ -215,7 +187,10 @@ endfunction
 function! s:Opener._newVSplit()
     let l:winwidth = winwidth('.')
 
-    if winnr('$') == 1
+    let onlyOneWin = (winnr("$") ==# 1)
+    let savesplitright = &splitright
+    if onlyOneWin
+        let &splitright = (g:NERDTreeWinPos ==# "left")
         let l:winwidth = g:NERDTreeWinSize
     endif
 
@@ -229,6 +204,7 @@ function! s:Opener._newVSplit()
     execute 'silent vertical resize ' . l:winwidth
 
     call nerdtree#exec(l:currentWindowNumber . 'wincmd w', 0)
+    let &splitright=savesplitright
 endfunction
 
 " FUNCTION: Opener.open(target) {{{1

lib/nerdtree/ui.vim

@@ -355,12 +355,15 @@ endfunction
 " scroll position
 function! s:UI.saveScreenState()
     let win = winnr()
-    call g:NERDTree.CursorToTreeWin()
     let self._screenState = {}
-    let self._screenState['oldPos'] = getpos(".")
+    try
-    let self._screenState['oldTopLine'] = line("w0")
+        call g:NERDTree.CursorToTreeWin()
-    let self._screenState['oldWindowSize']= winwidth("")
+        let self._screenState['oldPos'] = getpos(".")
-    call nerdtree#exec(win . "wincmd w", 1)
+        let self._screenState['oldTopLine'] = line("w0")
+        let self._screenState['oldWindowSize']= winwidth("")
+        call nerdtree#exec(win . "wincmd w", 1)
+    catch
+    endtry
 endfunction
 
 " FUNCTION: s:UI.setShowHidden(val) {{{1

plugin/NERD_tree.vim

@@ -170,10 +170,10 @@ 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