Specify both Python 2 and Python 3

Author: yssl

README.md

@@ -1,7 +1,5 @@
 # VIntSearch
 
-*Currently, this plugin only supports the vim compiled with python 2 support (+python).*
-
 VIntSearch is a vim plugin providing an integrated interface across various types of searches. It currently supports symbol search, text search, and file search.
 Search results are given in the quickfix window and a user can conviniently move forward / backward through the integrated search history.
 VIntSearch means **V**im **Int**egrated **Search**.
@@ -39,8 +37,10 @@ VIntSearch means **V**im **Int**egrated **Search**.
 - Manual install (not recommended)
     - Download this plugin and extract it in `~/.vim/`
 
-This plugin requires a version of vim with python support. You can check your vim with `:echo has('python')`.
-- Linux: If your vim doesn't support python, one of the easiest solutions would be installing a more featured version of vim by `sudo apt-get install vim-gtk-py2`.
+## Requirements
+
+This plugin requires a version of vim with Python 2 (+python) or Python 3 (+python3) support. You can check your vim with `:echo has('python')` or `:echo has('python3')`.
+- Ubuntu: If your vim doesn't support python, one of the easiest solutions would be installing a more featured version of vim by `sudo apt-get install vim-gtk`.
 - Windows: gvim for Windows is already equipped with python support.
 
 ## Getting Started

autoload/VIntSearch.vim

@@ -3,6 +3,17 @@
 " Author:       yssl <http://github.com/yssl>
 " License:      MIT License
 
+" Support for Python3 and Python2
+" from https://github.com/Valloric/YouCompleteMe
+function! s:UsingPython3()
+	if has('python3')
+		return 1
+	endif
+	return 0
+endfunction
+let s:using_python3 = s:UsingPython3()
+let s:pythonX_until_EOF = s:using_python3 ? "python3 << EOF" : "python << EOF"
+
 " wrappers
 function! VIntSearch#Cc(linenum, use_quickfix)
 	call s:Cc(a:linenum, a:use_quickfix)
@@ -384,14 +395,14 @@ function! s:ClearStack()
 endfunction
 
 function! s:PrintStack()
-python << EOF
+exec s:pythonX_until_EOF
 import vim
 def ltrunc(s, width, prefix=''):
-    if width >= len(s): prefix = ''
-    return prefix+s[-width+len(prefix):]
+	if width >= len(s): prefix = ''
+	return prefix+s[-width+len(prefix):]
 def rtrunc(s, width, postfix=''):
-    if width >= len(s): postfix = ''
-    return s[:width-len(postfix)]+postfix
+	if width >= len(s): postfix = ''
+	return s[:width-len(postfix)]+postfix
 def toWidthColMat(rowMat):
 	colMat = [[None]*len(rowMat) for c in range(len(rowMat[0]))]
 	for r in range(len(rowMat)):
@@ -413,7 +424,7 @@ for i in range(len(searchstack)+1):
 		ss = searchstack[i]
 		propMat.append([mark, str(i+1), ss['keyword'], ss['type'],\
 						ss['file'], ss['line'], \
-	   					ss['text'].lstrip().replace('\t',' ')]) 
+						ss['text'].lstrip().replace('\t',' ')]) 
 	else:
 		propMat.append([mark,'','','','','','']) 
 
@@ -614,7 +625,7 @@ function! s:GetRepoDirFrom(filepath)
 	if a:filepath==#''
 		return ''
 	endif
-python << EOF
+exec s:pythonX_until_EOF
 repodirs = vim.eval('g:vintsearch_repodirs')
 filepath = vim.eval('a:filepath')
 dir = os.path.dirname(filepath)
@@ -626,7 +637,7 @@ while True:
 			exist = True
 			break
 	if exist:
-	   break	
+		break	
 
 	prevdir = dir
 	dir = os.path.dirname(dir)
@@ -850,7 +861,7 @@ function! s:GetCtagsQFList(keyword)
 		redir END
 		let tags = []
 
-python << EOF
+exec s:pythonX_until_EOF
 	import vim
 
 	def splitTaglineByIndexes(tagline, indexes):

doc/VIntSearch.txt

@@ -42,13 +42,8 @@ VIntSearch means Vim Integrated Search.
 - Search keyword can be from a word under the cursor, visually selected text,
   or any string you type.
 
-This plugin requires a version of vim with python support.
-You can check your vim with `:echo has('python')`.
-
-- Linux: If your vim doesn't support python, one of the easiest solutions 
-would be installing a more featured version of vim by `sudo apt-get install vim-gtk`.
-
-- Windows: gvim for Windows is already equipped with python support.
+This plugin requires a version of vim with Python 2 (+python) or Python 3 (+python3) 
+support. You can check your vim with `:echo has('python')` or `:echo has('python3')`.
 
 ==============================================================================
 2. Getting Started                                 *VIntSearch-gettingstarted*

plugin/VIntSearch.vim

@@ -12,6 +12,14 @@ set cpo&vim
 
 """""""""""""""""""""""""""""""""""""""""""""
 
+" vim version checking
+if !has('python3') && !has('python')
+	echohl WarningMsg
+	echomsg 'VIntSearch unavailable: requires vim with Python support'
+	echohl None
+	finish
+endif
+
 "" global variables
 if !exists('g:vintsearch_searchpathmode')
 	" search path is the root dir of grep search path tree or the dir where tags