Calculate real path for symlinked IPython package in sysinfo

See discussion on  #5725

IPython/utils/sysinfo.py

@@ -1,170 +1,170 b''
 # encoding: utf-8
 """
 Utilities for getting information about IPython and the system it's running in.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2008-2011  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
 import platform
 import pprint
 import sys
 import subprocess
 
 from IPython.core import release
 from IPython.utils import py3compat, _sysinfo, encoding
 
 #-----------------------------------------------------------------------------
 # Code
 #-----------------------------------------------------------------------------
 
 def pkg_commit_hash(pkg_path):
     """Get short form of commit hash given directory `pkg_path`
 
     We get the commit hash from (in order of preference):
 
     * IPython.utils._sysinfo.commit
     * git output, if we are in a git repository
 
     If these fail, we return a not-found placeholder tuple
 
     Parameters
     ----------
     pkg_path : str
        directory containing package
        only used for getting commit from active repo
 
     Returns
     -------
     hash_from : str
        Where we got the hash from - description
     hash_str : str
        short form of hash
     """
     # Try and get commit from written commit text file
     if _sysinfo.commit:
         return "installation", _sysinfo.commit
 
     # maybe we are in a repository
     proc = subprocess.Popen('git rev-parse --short HEAD',
                             stdout=subprocess.PIPE,
                             stderr=subprocess.PIPE,
                             cwd=pkg_path, shell=True)
     repo_commit, _ = proc.communicate()
     if repo_commit:
         return 'repository', repo_commit.strip()
     return '(none found)', '<not found>'
 
 
 def pkg_info(pkg_path):
     """Return dict describing the context of this package
 
     Parameters
     ----------
     pkg_path : str
        path containing __init__.py for package
 
     Returns
     -------
     context : dict
        with named parameters of interest
     """
     src, hsh = pkg_commit_hash(pkg_path)
     return dict(
         ipython_version=release.version,
         ipython_path=pkg_path,
         commit_source=src,
         commit_hash=hsh,
         sys_version=sys.version,
         sys_executable=sys.executable,
         sys_platform=sys.platform,
         platform=platform.platform(),
         os_name=os.name,
         default_encoding=encoding.DEFAULT_ENCODING,
         )
 
 def get_sys_info():
     """Return useful information about IPython and the system, as a dict."""
     p = os.path
-    path = p.dirname(p.abspath(p.join(__file__, '..')))
+    path = p.realpath(p.dirname(p.abspath(p.join(__file__, '..'))))
     return pkg_info(path)
 
 @py3compat.doctest_refactor_print
 def sys_info():
     """Return useful information about IPython and the system, as a string.
 
     Examples
     --------
     ::
     
         In [2]: print sys_info()
         {'commit_hash': '144fdae',      # random
          'commit_source': 'repository',
          'ipython_path': '/home/fperez/usr/lib/python2.6/site-packages/IPython',
          'ipython_version': '0.11.dev',
          'os_name': 'posix',
          'platform': 'Linux-2.6.35-22-generic-i686-with-Ubuntu-10.10-maverick',
          'sys_executable': '/usr/bin/python',
          'sys_platform': 'linux2',
          'sys_version': '2.6.6 (r266:84292, Sep 15 2010, 15:52:39) \\n[GCC 4.4.5]'}
     """
     return pprint.pformat(get_sys_info())
 
 def _num_cpus_unix():
     """Return the number of active CPUs on a Unix system."""
     return os.sysconf("SC_NPROCESSORS_ONLN")
 
 
 def _num_cpus_darwin():
     """Return the number of active CPUs on a Darwin system."""
     p = subprocess.Popen(['sysctl','-n','hw.ncpu'],stdout=subprocess.PIPE)
     return p.stdout.read()
 
 
 def _num_cpus_windows():
     """Return the number of active CPUs on a Windows system."""
     return os.environ.get("NUMBER_OF_PROCESSORS")
 
 
 def num_cpus():
    """Return the effective number of CPUs in the system as an integer.
 
    This cross-platform function makes an attempt at finding the total number of
    available CPUs in the system, as returned by various underlying system and
    python calls.
 
    If it can't find a sensible answer, it returns 1 (though an error *may* make
    it return a large positive number that's actually incorrect).
    """
 
    # Many thanks to the Parallel Python project (http://www.parallelpython.com)
    # for the names of the keys we needed to look up for this function.  This
    # code was inspired by their equivalent function.
 
    ncpufuncs = {'Linux':_num_cpus_unix,
                 'Darwin':_num_cpus_darwin,
                 'Windows':_num_cpus_windows,
                 # On Vista, python < 2.5.2 has a bug and returns 'Microsoft'
                 # See http://bugs.python.org/issue1082 for details.
                 'Microsoft':_num_cpus_windows,
                 }
 
    ncpufunc = ncpufuncs.get(platform.system(),
                             # default to unix version (Solaris, AIX, etc)
                             _num_cpus_unix)
 
    try:
        ncpus = max(1,int(ncpufunc()))
    except:
        ncpus = 1
    return ncpus