Le jeudi 09 juin 2011 à 08:16 +0200, Georg Brandl a écrit :
> On 06/09/11 02:00, brian.curtin wrote:
> > http://hg.python.org/cpython/rev/88e318166eaf
> > changeset: 70713:88e318166eaf
> > branch: 3.2
> > parent: 70700:0aa3064d1cef
> > user: Brian Curtin <br...@python.org>
> > date: Wed Jun 08 18:17:18 2011 -0500
> > summary:
> > Fix #11583. Changed os.path.isdir to use GetFileAttributes instead of
> > os.stat.
> >
> > By changing to the Windows GetFileAttributes API in nt._isdir we can figure
> > out if the path is a directory without opening the file via os.stat. This
> > has
> > the minor benefit of speeding up os.path.isdir by at least 2x for regular
> > files and 10-15x improvements were seen on symbolic links (which opened the
> > file multiple times during os.stat). Since os.path.isdir is used in
> > several places on interpreter startup, we get a minor speedup in startup
> > time.
> >
> > files:
> > Lib/ntpath.py | 13 ++++++++++
> > Misc/NEWS | 3 ++
> > Modules/posixmodule.c | 37 +++++++++++++++++++++++++++++++
> > 3 files changed, 53 insertions(+), 0 deletions(-)
> >
> >
> > diff --git a/Lib/ntpath.py b/Lib/ntpath.py
> > --- a/Lib/ntpath.py
> > +++ b/Lib/ntpath.py
> > @@ -672,3 +672,16 @@
> > def sameopenfile(f1, f2):
> > """Test whether two file objects reference the same file"""
> > return _getfileinformation(f1) == _getfileinformation(f2)
> > +
> > +
> > +try:
> > + # The genericpath.isdir implementation uses os.stat and checks the mode
> > + # attribute to tell whether or not the path is a directory.
> > + # This is overkill on Windows - just pass the path to GetFileAttributes
> > + # and check the attribute from there.
> > + from nt import _isdir
> > +except ImportError:
> > + from genericpath import isdir as _isdir
> > +
> > +def isdir(path):
> > + return _isdir(path)
>
> Not that it matters, but ISTM that this would be faster as
>
> try:
> from nt import _isdir as isdir
> except ImportError:
> pass
I would matter if _isdir() had a docstring, but it doesn't :-)
genericpath.isdir() has the following doc:
def isdir(s):
"""Return true if the pathname refers to an existing directory."""
Victor
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