Fix sub-dir functionality in posts stored in a DBKnowledgeRepository (#171)

Author: sryza

knowledge_repo/repositories/dbrepository.py

@@ -204,15 +204,15 @@ def _kp_read_ref(self, path, reference, revision=None):
         return data
 
     def _kp_dir(self, path, parent=None, revision=None):
-        if parent:
-            path = posixpath.join(path, parent)
+        ref_prefix = parent + '/' if parent else ''
         revision = revision or self._kp_get_revision(path, enforce_exists=True)
         refs = (self.session.query(self.PostRef.ref)
                             .filter(self.PostRef.path == path)
+                            .filter(self.PostRef.ref.like(ref_prefix + '%'))
                             .filter(self.PostRef.revision == revision)).all()
         for (ref,) in refs:
             if ref is not None:
-                yield ref
+                yield posixpath.relpath(ref, parent or '')
 
     def _kp_has_ref(self, path, reference, revision=None):
         revision = revision or self._kp_get_revision(path, enforce_exists=True)