util: add functions to check symlink/exec bits

These are not yet used.

mercurial/posix.py

@@ -557,3 +557,11 b' class unixdomainserver(socket.socket):'
         if self.realpath != self.path:
             okayifmissing(os.unlink, self.realpath)
             okayifmissing(os.rmdir, os.path.dirname(self.realpath))
+
+def statislink(st):
+    '''check whether a stat result is a symlink'''
+    return st and stat.S_ISLNK(st.st_mode)
+
+def statisexec(st):
+    '''check whether a stat result is an executable file'''
+    return st and (st.st_mode & 0100 != 0)

mercurial/util.py

@@ -65,6 +65,8 b' spawndetached = platform.spawndetached'
 split = platform.split
 sshargs = platform.sshargs
 statfiles = getattr(osutil, 'statfiles', platform.statfiles)
+statisexec = platform.statisexec
+statislink = platform.statislink
 termwidth = platform.termwidth
 testpid = platform.testpid
 umask = platform.umask

mercurial/windows.py

@@ -337,3 +337,11 b' def lookupreg(key, valname=None, scope=N'
             pass
 
 expandglobs = True
+
+def statislink(st):
+    '''check whether a stat result is a symlink'''
+    return False
+
+def statisexec(st):
+    '''check whether a stat result is an executable file'''
+    return False