diff -r 9b3f95d9783d -r beede158ea8a mercurial/util.py
--- a/mercurial/util.py	Fri Dec 22 23:17:04 2017 +0800
+++ b/mercurial/util.py	Sat Dec 30 21:07:03 2017 -0500
@@ -109,6 +109,7 @@
 expandglobs = platform.expandglobs
 explainexit = platform.explainexit
 findexe = platform.findexe
+getfstype = platform.getfstype
 gethgcmd = platform.gethgcmd
 getuser = platform.getuser
 getpid = os.getpid
@@ -1519,13 +1520,6 @@
 
     return ''.join(result)
 
-def getfstype(dirpath):
-    '''Get the filesystem type name from a directory (best-effort)
-
-    Returns None if we are unsure. Raises OSError on ENOENT, EPERM, etc.
-    '''
-    return getattr(osutil, 'getfstype', lambda x: None)(dirpath)
-
 def checknlink(testfile):
     '''check whether hardlink count reporting works properly'''