--- a/runtime/indent/tex.vim
+++ b/runtime/indent/tex.vim
@@ -1,12 +1,16 @@
-" Vim indent file
-" Language:     LaTeX
-" Maintainer:   Yichao Zhou <broken.zhou AT gmail.com>
-" Created:      Sat, 16 Feb 2002 16:50:19 +0100
-" Version: 1.0.0
+" Vim indent file for TeX
+" Language:             TeX
+" Maintainer:           Christian Brabandt <cb@256bit.org>
+" Previous Maintainer:  YiChao Zhou <broken.zhou AT gmail.com>
+" Latest Revision:      2017-05-03
+" Version:              0.9.3
+" Repository:           https://github.com/chrisbra/vim-tex-indent
+" Documention:          :h ft-tex-indent
+" Created:              Sat, 16 Feb 2002 16:50:19 +0100
 "   Please email me if you found something I can do.  Comments, bug report and
 "   feature request are welcome.
 
-" Last Update:  {{{
+" Last Update:  {{{1
 "               25th Sep 2002, by LH :
 "               (*) better support for the option
 "               (*) use some regex instead of several '||'.
@@ -15,122 +19,64 @@
 "               2005/06/15, Moshe Kaminsky <kaminsky AT math.huji.ac.il>
 "               (*) New variables:
 "                   g:tex_items, g:tex_itemize_env, g:tex_noindent_env
-"               2011/3/6, by Yichao Zhou <broken.zhou AT gmail.com>
+"               2011/3/6, by Zhou YiChao <broken.zhou AT gmail.com>
 "               (*) Don't change indentation of lines starting with '%'
 "                   I don't see any code with '%' and it doesn't work properly
 "                   so I add some code.
 "               (*) New features: Add smartindent-like indent for "{}" and  "[]".
 "               (*) New variables: g:tex_indent_brace
-"               2011/9/25, by Yichao Zhou <broken.zhou AT gmail.com>
+"               2011/9/25, by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Bug fix: smartindent-like indent for "[]"
 "               (*) New features: Align with "&".
 "               (*) New variable: g:tex_indent_and.
-"               2011/10/23 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2011/10/23 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Bug fix: improve the smartindent-like indent for "{}" and
 "               "[]".
-"               2012/02/27 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2012/02/27 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Bug fix: support default folding marker.
 "               (*) Indent with "&" is not very handy.  Make it not enable by
 "               default.
-"               2012/03/06 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2012/03/06 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Modify "&" behavior and make it default again.  Now "&"
 "               won't align when there are more then one "&" in the previous
 "               line.
 "               (*) Add indent "\left(" and "\right)"
 "               (*) Trust user when in "verbatim" and "lstlisting"
-"               2012/03/11 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2012/03/11 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Modify "&" so that only indent when current line start with
 "                   "&".
-"               2012/03/12 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2012/03/12 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Modify indentkeys.
-"               2012/03/18 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2012/03/18 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Add &cpo
-"               2013/05/02 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2013/05/02 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Fix problem about GetTeXIndent checker. Thank Albert Netymk
 "                   for reporting this.
-"               2014/06/23 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2014/06/23 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Remove the feature g:tex_indent_and because it is buggy.
 "               (*) If there is not any obvious indentation hints, we do not
 "                   alert our user's current indentation.
 "               (*) g:tex_indent_brace now only works if the open brace is the
 "                   last character of that line.
-"               2014/08/03 by Yichao Zhou <broken.zhou AT gmail.com>
+"               2014/08/03 by Zhou Yichao <broken.zhou AT gmail.com>
 "               (*) Indent current line if last line has larger indentation
-"               2016/11/08 by Yichao Zhou <broken.zhou AT gmail.com>
-"               (*) Fix problems for \[ and \].  Thanks Bruno for reporting.
-"               2017/04/30 by Yichao Zhou <broken.zhou AT gmail.com>
-"               (*) Fix a bug between g:tex_noindent_env and g:tex_indent_items
-"                   Now g:tex_noindent_env='document\|verbatim\|itemize' (Emacs
-"                   style) is supported.  Thanks Miles Wheeler for reporting.
-"               2018/02/07 by Yichao Zhou <broken.zhou AT gmail.com>
-"               (*) Make indentation more smart in the normal mode
+"               2014/08/09 by Zhou Yichao <broken.zhou AT gmail.com>
+"               (*) Add missing return value for s:GetEndIndentation(...)
+"               2017/05/02: new maintainer Christian Brabandt
+"               2017/05/02: use shiftwidth() function
+"               2017/05/02: do not add indent when environment starts and ends
+"                           at previous line
+"               2017/05/03: release 0.9.3 submitted for inclusion with Vim
 "
 " }}}
-
-" Document: {{{
-"
-" To set the following options (ok, currently it's just one), add a line like
-"   let g:tex_indent_items = 1
-" to your ~/.vimrc.
-"
-" * g:tex_indent_brace
-"
-"   If this variable is unset or non-zero, it will use smartindent-like style
-"   for "{}" and "[]".  Now this only works if the open brace is the last
-"   character of that line.
-"
-"         % Example 1
-"         \usetikzlibrary{
-"           external
-"         }
-"
-"         % Example 2
-"         \tikzexternalize[
-"           prefix=tikz]
-"
-" * g:tex_indent_items
-"
-"   If this variable is set, item-environments are indented like Emacs does
-"   it, i.e., continuation lines are indented with a shiftwidth.
-"
-"              set                      unset
-"   ------------------------------------------------------
-"       \begin{itemize}            \begin{itemize}
-"         \item blablabla            \item blablabla
-"           bla bla bla              bla bla bla
-"         \item blablabla            \item blablabla
-"           bla bla bla              bla bla bla
-"       \end{itemize}              \end{itemize}
-"
-"
-" * g:tex_items
-"
-"   A list of tokens to be considered as commands for the beginning of an item
-"   command. The tokens should be separated with '\|'. The initial '\' should
-"   be escaped. The default is '\\bibitem\|\\item'.
-"
-" * g:tex_itemize_env
-"
-"   A list of environment names, separated with '\|', where the items (item
-"   commands matching g:tex_items) may appear. The default is
-"   'itemize\|description\|enumerate\|thebibliography'.
-"
-" * g:tex_noindent_env
-"
-"   A list of environment names. separated with '\|', where no indentation is
-"   required. The default is 'document\|verbatim'.
-" }}}
-
-" Only define the function once
+" Only define the function once {{{1
 if exists("b:did_indent")
     finish
 endif
 
 let s:cpo_save = &cpo
 set cpo&vim
-
-" Define global variable {{{
-
+" Define global variable {{{1
 let b:did_indent = 1
 
 if !exists("g:tex_indent_items")
@@ -147,7 +93,7 @@ if g:tex_indent_items
         let g:tex_itemize_env = 'itemize\|description\|enumerate\|thebibliography'
     endif
     if !exists('g:tex_items')
-        let g:tex_items = '\\bibitem\|\\item'
+        let g:tex_items = '\\bibitem\|\\item' 
     endif
 else
     let g:tex_items = ''
@@ -156,17 +102,17 @@ endif
 if !exists("g:tex_noindent_env")
     let g:tex_noindent_env = 'document\|verbatim\|lstlisting'
 endif "}}}
-
-" VIM Setting " {{{
+" VIM Setting " {{{1
 setlocal autoindent
 setlocal nosmartindent
 setlocal indentexpr=GetTeXIndent()
 setlocal indentkeys&
 exec 'setlocal indentkeys+=[,(,{,),},],\&' . substitute(g:tex_items, '^\|\(\\|\)', ',=', 'g')
 let g:tex_items = '^\s*' . substitute(g:tex_items, '^\(\^\\s\*\)*', '', '')
+
+let b:undo_indent = 'setlocal indentexpr< indentkeys< smartindent< autoindent<'
 " }}}
-
-function! GetTeXIndent() " {{{
+function! GetTeXIndent() " {{{1
     " Find a non-blank line above the current line.
     let lnum = prevnonblank(v:lnum - 1)
     let cnum = v:lnum
@@ -178,7 +124,7 @@ function! GetTeXIndent() " {{{
 
     " At the start of the file use zero indent.
     if lnum == 0
-        return 0
+        return 0 
     endif
 
     let line = substitute(getline(lnum), '\s*%.*', '','g')     " last line
@@ -192,9 +138,9 @@ function! GetTeXIndent() " {{{
             return indent(v:lnum)
         end
     endif
-
+    
     if lnum == 0
-        return 0
+        return 0 
     endif
 
     let ind = indent(lnum)
@@ -205,16 +151,12 @@ function! GetTeXIndent() " {{{
         return indent(v:lnum)
     endif
 
-    " Add a 'shiftwidth' after beginning of environments.
-    " Don't add it for \begin{document} and \begin{verbatim}
-    " if line =~ '^\s*\\begin{\(.*\)}'  && line !~ 'verbatim'
-    " LH modification : \begin does not always start a line
-    " ZYC modification : \end after \begin won't cause wrong indent anymore
-    if line =~ '\\begin{.*}' 
-        if line !~ g:tex_noindent_env
-            let ind = ind + shiftwidth()
-            let stay = 0
-        endif
+    " Add a 'shiftwidth' after beginning of environments
+    " But don't do it for g:tex_noindent_env or when it also ends at the
+    " previous line.
+    if line =~ '\\begin{.*}'  && line !~ '\\end{.*}' && line !~ g:tex_noindent_env
+        let ind = ind + shiftwidth()
+        let stay = 0
 
         if g:tex_indent_items
             " Add another sw for item-environments
@@ -248,27 +190,29 @@ function! GetTeXIndent() " {{{
     endif
 
     if g:tex_indent_brace
-        if line =~ '[[{]$'
+        let char = line[strlen(line)-1]
+        if char == '[' || char == '{'
             let ind += shiftwidth()
             let stay = 0
         endif
 
-        if cline =~ '^\s*\\\?[\]}]' && s:CheckPairedIsLastCharacter(v:lnum, indent(v:lnum))
+        let cind = indent(v:lnum)
+        let char = cline[cind]
+        if (char == ']' || char == '}') &&
+                    \ s:CheckPairedIsLastCharacter(v:lnum, cind)
             let ind -= shiftwidth()
             let stay = 0
         endif
 
-        if line !~ '^\s*\\\?[\]}]'
-            for i in range(indent(lnum)+1, strlen(line)-1)
-                let char = line[i]
-                if char == ']' || char == '}'
-                    if s:CheckPairedIsLastCharacter(lnum, i)
-                        let ind -= shiftwidth()
-                        let stay = 0
-                    endif
+        for i in range(indent(lnum)+1, strlen(line)-1)
+            let char = line[i]
+            if char == ']' || char == '}'
+                if s:CheckPairedIsLastCharacter(lnum, i)
+                    let ind -= shiftwidth()
+                    let stay = 0
                 endif
-            endfor
-        endif
+            endif
+        endfor
     endif
 
     " Special treatment for 'item'
@@ -287,9 +231,8 @@ function! GetTeXIndent() " {{{
         endif
     endif
 
-    if stay && mode() == 'i'
-        " If there is no obvious indentation hint, and indentation is triggered
-        " in insert mode, we trust our user.
+    if stay
+        " If there is no obvious indentation hint, we trust our user.
         if empty(cline)
             return ind
         else
@@ -299,8 +242,7 @@ function! GetTeXIndent() " {{{
         return ind
     endif
 endfunction "}}}
-
-function! s:GetLastBeginIndentation(lnum) " {{{
+function! s:GetLastBeginIndentation(lnum) " {{{1
     let matchend = 1
     for lnum in range(a:lnum-1, max([a:lnum - g:tex_max_scan_line, 1]), -1)
         let line = getline(lnum)
@@ -311,19 +253,19 @@ function! s:GetLastBeginIndentation(lnum
             let matchend -= 1
         endif
         if matchend == 0
+            if line =~ g:tex_itemize_env
+                return indent(lnum) + 2 * shiftwidth()
+            endif
             if line =~ g:tex_noindent_env
                 return indent(lnum)
             endif
-            if line =~ g:tex_itemize_env
-                return indent(lnum) + 2 * shiftwidth()
-            endif
             return indent(lnum) + shiftwidth()
         endif
     endfor
     return -1
 endfunction
 
-function! s:GetEndIndentation(lnum) " {{{
+function! s:GetEndIndentation(lnum) " {{{1
     if getline(a:lnum) =~ '\\begin{.*}.*\\end{.*}'
         return -1
     endif
@@ -350,15 +292,12 @@ endfunction
 
 " Most of the code is from matchparen.vim
 function! s:CheckPairedIsLastCharacter(lnum, col) "{{{
+    " Get the character under the cursor and check if it's in 'matchpairs'.
     let c_lnum = a:lnum
     let c_col = a:col+1
 
-    let line = getline(c_lnum)
-    if line[c_col-1] == '\'
-        let c_col = c_col + 1
-    endif
-    let c = line[c_col-1]
 
+    let c = getline(c_lnum)[c_col-1]
     let plist = split(&matchpairs, '.\zs[:,]')
     let i = index(plist, c)
     if i < 0
@@ -407,8 +346,8 @@ function! s:CheckPairedIsLastCharacter(l
     endif
 
     return 0
-endfunction "}}}
-
+endfunction
+" Reset cpo setting {{{1
 let &cpo = s:cpo_save
 unlet s:cpo_save