Rewrite copytree as copyfiles

This inverts the logic of copytree to allow copying single files at
the top level.

mercurial/commands.py

@@ -607,7 +607,7 b' def clone(ui, source, dest=None, **opts)'
         # we use a lock here because because we're not nicely ordered
         l = lock.lock(os.path.join(source, ".hg", "lock"))
 
-        util.copytree(os.path.join(source, ".hg"), os.path.join(dest, ".hg"),
+        util.copyfiles(os.path.join(source, ".hg"), os.path.join(dest, ".hg"),
                       copyfile)
 
         for fn in "dirstate", "lock", "hgrc", "localtags":

mercurial/util.py

@@ -217,20 +217,17 b' def rename(src, dst):'
         os.unlink(dst)
         os.rename(src, dst)
 
-def copytree(src, dst, copyfile):
+def copyfiles(src, dst, copyfile):
     """Copy a directory tree, files are copied using 'copyfile'."""
-    names = os.listdir(src)
-    os.mkdir(dst)
 
-    for name in names:
-        srcname = os.path.join(src, name)
-        dstname = os.path.join(dst, name)
-        if os.path.isdir(srcname):
-            copytree(srcname, dstname, copyfile)
-        elif os.path.isfile(srcname):
-            copyfile(srcname, dstname)
-        else:
-            pass
+    if os.path.isdir(src):
+        os.mkdir(dst)
+        for name in os.listdir(src):
+            srcname = os.path.join(src, name)
+            dstname = os.path.join(dst, name)
+            copyfiles(srcname, dstname, copyfile)
+    else:
+        copyfile(src, dst)
 
 def opener(base):
     """