[Python-checkins] python/dist/src/Lib glob.py,1.11,1.12
jlgijsbers at users.sourceforge.net
jlgijsbers at users.sourceforge.net
Sat Jan 8 14:13:22 CET 2005
Update of /cvsroot/python/python/dist/src/Lib
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv8739/Lib
Modified Files:
glob.py
Log Message:
Patch #943206:
`glob.glob()` currently calls itself recursively to build a list of matches of
the dirname part of the pattern and then filters by the basename part. This is
effectively BFS. ``glob.glob('*/*/*/*/*/foo')`` will build a huge list of all
directories 5 levels deep even if only a handful of them contain a ``foo``
entry. A generator-based recusion would never have to store these list at once
by implementing DFS. This patch converts the `glob` function to an `iglob`
recursive generator . `glob()` now just returns ``list(iglob(pattern))``.
I also cleaned up the code a bit (reduced duplicate `has_magic()` checks and
created a second `glob0` helper func so that the main loop need not be
duplicated).
Thanks to Cherniavsky Beni for the patch!
Index: glob.py
===================================================================
RCS file: /cvsroot/python/python/dist/src/Lib/glob.py,v
retrieving revision 1.11
retrieving revision 1.12
diff -u -d -r1.11 -r1.12
--- glob.py 30 Aug 2004 10:19:54 -0000 1.11
+++ glob.py 8 Jan 2005 13:13:14 -0000 1.12
@@ -4,7 +4,7 @@
import fnmatch
import re
-__all__ = ["glob"]
+__all__ = ["glob", "iglob"]
def glob(pathname):
"""Return a list of paths matching a pathname pattern.
@@ -12,35 +12,42 @@
The pattern may contain simple shell-style wildcards a la fnmatch.
"""
+ return list(iglob(pathname))
+
+def iglob(pathname):
+ """Return a list of paths matching a pathname pattern.
+
+ The pattern may contain simple shell-style wildcards a la fnmatch.
+
+ """
if not has_magic(pathname):
if os.path.lexists(pathname):
- return [pathname]
- else:
- return []
+ yield pathname
+ return
dirname, basename = os.path.split(pathname)
if not dirname:
- return glob1(os.curdir, basename)
- elif has_magic(dirname):
- list = glob(dirname)
+ for name in glob1(os.curdir, basename):
+ yield name
+ return
+ if has_magic(dirname):
+ dirs = iglob(dirname)
else:
- list = [dirname]
- if not has_magic(basename):
- result = []
- for dirname in list:
- if basename or os.path.isdir(dirname):
- name = os.path.join(dirname, basename)
- if os.path.lexists(name):
- result.append(name)
+ dirs = [dirname]
+ if has_magic(basename):
+ glob_in_dir = glob1
else:
- result = []
- for dirname in list:
- sublist = glob1(dirname, basename)
- for name in sublist:
- result.append(os.path.join(dirname, name))
- return result
+ glob_in_dir = glob0
+ for dirname in dirs:
+ for name in glob_in_dir(dirname, basename):
+ yield os.path.join(dirname, name)
+
+# These 2 helper functions non-recursively glob inside a literal directory.
+# They return a list of basenames. `glob1` accepts a pattern while `glob0`
+# takes a literal basename (so it only has to check for its existence).
def glob1(dirname, pattern):
- if not dirname: dirname = os.curdir
+ if not dirname:
+ dirname = os.curdir
try:
names = os.listdir(dirname)
except os.error:
@@ -49,6 +56,17 @@
names=filter(lambda x: x[0]!='.',names)
return fnmatch.filter(names,pattern)
+def glob0(dirname, basename):
+ if basename == '':
+ # `os.path.split()` returns an empty basename for paths ending with a
+ # directory separator. 'q*x/' should match only directories.
+ if os.isdir(dirname):
+ return [basename]
+ else:
+ if os.path.lexists(os.path.join(dirname, basename)):
+ return [basename]
+ return []
+
magic_check = re.compile('[*?[]')
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