Merge pull request #5390 from minrk/finish-5333

finish PR  #5333

IPython/html/utils.py

@@ -102,10 +102,22 b" def is_hidden(abs_path, abs_root=''):"
     if any(part.startswith('.') for part in inside_root.split(os.sep)):
         return True
     
+    # check that dirs can be listed
+    # may fail on Windows junctions or non-user-readable dirs
+    if os.path.isdir(abs_path):
+        try:
+            os.listdir(abs_path)
+        except OSError:
+            return True
+    
     # check UF_HIDDEN on any location up to root
     path = abs_path
     while path and path.startswith(abs_root) and path != abs_root:
-        st = os.stat(path)
+        try:
+            # may fail on Windows junctions
+            st = os.stat(path)
+        except OSError:
+            return True
         if getattr(st, 'st_flags', 0) & UF_HIDDEN:
             return True
         path = os.path.dirname(path)