A couple more small changes,

also added __init__ file to new utils test dir

IPython/nbconvert/utils/pandoc.py

@@ -1,135 +1,128 b''
 """Utility for calling pandoc"""
 #-----------------------------------------------------------------------------
-# Copyright (c) 2013 the IPython Development Team.
+# Copyright (c) 2014 the IPython Development Team.
 #
 # Distributed under the terms of the Modified BSD License.
 #
 # The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
-
 from __future__ import print_function
 
 # Stdlib imports
 import subprocess
 import re
 import warnings
 from io import TextIOWrapper, BytesIO
 
 # IPython imports
 from IPython.utils.py3compat import cast_bytes
 from IPython.utils.version import check_version
 from IPython.utils.process import is_cmd_found, FindCmdError
 
-
 from .exceptions import ConversionException
 
 #-----------------------------------------------------------------------------
 # Classes and functions
 #-----------------------------------------------------------------------------
 _minimal_version = "1.12.1"
 
 def pandoc(source, fmt, to, extra_args=None, encoding='utf-8'):
     """Convert an input string in format `from` to format `to` via pandoc.
 
     Parameters
     ----------
     source : string
       Input string, assumed to be valid format `from`.
     fmt : string
       The name of the input format (markdown, etc.)
     to : string
       The name of the output format (html, etc.)
 
     Returns
     -------
     out : unicode
       Output as returned by pandoc.
 
     Exceptions
     ----------
     This function will raise PandocMissing if pandoc is not installed.
     Any error messages generated by pandoc are printed to stderr.
 
     """
     cmd = ['pandoc', '-f', fmt, '-t', to]
     if extra_args:
         cmd.extend(extra_args)
 
     # this will raise an exception that will pop us out of here
     check_pandoc_version()
     
     # we can safely continue
     p = subprocess.Popen(cmd, stdin=subprocess.PIPE, stdout=subprocess.PIPE)
     out, _ = p.communicate(cast_bytes(source, encoding))
     out = TextIOWrapper(BytesIO(out), encoding, 'replace').read()
     return out.rstrip('\n')
 
 
 def get_pandoc_version():
     """Gets the Pandoc version if Pandoc is installed.
     
     Return
     ------
     If the minimal version is not met, it will probe Pandoc for its version, cache it and return that value.
     If the minimal version is met, it will return the cached version and stop probing Pandoc 
     (unless `clean_cache()` is called).
 
     Exceptions
     ----------
     PandocMissing will be raised if pandoc is unavailable.
     """
     global __version
 
-    if __version is not None:
-        return __version
-    else:
+    if __version is None:
         if not is_cmd_found('pandoc'):
             raise PandocMissing()
 
         out = subprocess.check_output( ['pandoc', '-v'], universal_newlines=True)
         pv_re = re.compile(r'(\d{0,3}\.\d{0,3}\.\d{0,3})')
         __version = pv_re.search(out).group(0)
         return __version
 
 
 def check_pandoc_version():
     """Returns True if minimal pandoc version is met.
 
     Exceptions
     ----------
     PandocMissing will be raised if pandoc is unavailable.
     """
     v = get_pandoc_version()
     ok = check_version(v , _minimal_version )
     if not ok:
         warnings.warn( "You are using an old version of pandoc (%s)\n" % v + 
                        "Recommended version is %s.\nTry updating." % _minimal_version + 
                        "http://johnmacfarlane.net/pandoc/installing.html.\nContinuing with doubts...",
                        RuntimeWarning, stacklevel=2)
     return ok
 
 #-----------------------------------------------------------------------------
 # Exception handling
 #-----------------------------------------------------------------------------
 class PandocMissing(ConversionException):
     """Exception raised when Pandoc is missing. """
     def __init__(self, *args, **kwargs):
         super(PandocMissing, self).__init__( "Pandoc wasn't found.\n" +
                                              "Please check that pandoc is installed:\n" +
                                              "http://johnmacfarlane.net/pandoc/installing.html" )
 
 #-----------------------------------------------------------------------------
 # Internal state management
 #-----------------------------------------------------------------------------
 def clean_cache():
     global __version
     __version = None
 
 __version = None
-
-
-

IPython/nbconvert/utils/tests/test_pandoc.py

@@ -1,63 +1,62 b''
 """Test Pandoc module"""
-
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2014 The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 import os
 
 from IPython.testing import decorators as dec
 
 from .base import TestsBase
 from ..utils import pandoc
 
 #-----------------------------------------------------------------------------
 # Classes and functions
 #-----------------------------------------------------------------------------
 class TestPandoc(TestsBase):
     """Collection of Pandoc tests"""
 
     def __init__(self, *args, **kwargs):
         super(TestPandoc, self).__init__(*args, **kwargs)
         self.original_env = os.environ.copy()
 
     @dec.onlyif_cmds_exist('pandoc')
     def test_pandoc_available(self):
         """ Test behaviour that pandoc functions raise PandocMissing as documented """
         pandoc.clean_cache()
 
         os.environ["PATH"] = ""
         assert pandoc_function_raised_missing(pandoc.get_pandoc_version) == True
         assert pandoc_function_raised_missing(pandoc.check_pandoc_version) == True
         assert pandoc_function_raised_missing(pandoc.pandoc, "", "markdown", "html") == True
 
         # original_env["PATH"] should contain pandoc
         os.environ["PATH"] = self.original_env["PATH"]
         assert pandoc_function_raised_missing(pandoc.get_pandoc_version) == False
         assert pandoc_function_raised_missing(pandoc.check_pandoc_version) == False
         assert pandoc_function_raised_missing(pandoc.pandoc, "", "markdown", "html") == False
         
     @dec.onlyif_cmds_exist('pandoc')
     def test_minimal_version(self):
         original_minversion = pandoc._minimal_version
 
         pandoc._minimal_version = "120.0"
         assert not pandoc.check_pandoc_version()
 
         pandoc._minimal_version = pandoc.get_pandoc_version()
         assert pandoc.check_pandoc_version()
 
 
 def pandoc_function_raised_missing(f, *args, **kwargs):
     try:
         f(*args, **kwargs)
     except pandoc.PandocMissing:
         return True
     else:
         return False