patch [ 1105730 ] Faster commonprefix in macpath, ntpath, etc.
diff --git a/Lib/os2emxpath.py b/Lib/os2emxpath.py
index 4c64324..5b1cb18 100644
--- a/Lib/os2emxpath.py
+++ b/Lib/os2emxpath.py
@@ -173,14 +173,13 @@
def commonprefix(m):
"Given a list of pathnames, returns the longest common leading component"
if not m: return ''
- prefix = m[0]
- for item in m:
- for i in range(len(prefix)):
- if prefix[:i+1] != item[:i+1]:
- prefix = prefix[:i]
- if i == 0: return ''
- break
- return prefix
+ s1 = min(m)
+ s2 = max(m)
+ n = min(len(s1), len(s2))
+ for i in xrange(n):
+ if s1[i] != s2[i]:
+ return s1[:i]
+ return s1[:n]
# Get size, mtime, atime of files.