diff --git a/kallithea/lib/vcs/backends/hg/repository.py b/kallithea/lib/vcs/backends/hg/repository.py
--- a/kallithea/lib/vcs/backends/hg/repository.py
+++ b/kallithea/lib/vcs/backends/hg/repository.py
@@ -272,7 +272,7 @@ class MercurialRepository(BaseRepository
             self.get_changeset(rev1)
         self.get_changeset(rev2)
         if path:
-            file_filter = mercurial.match.exact(path)
+            file_filter = mercurial.match.exact([safe_bytes(path)])
         else:
             file_filter = None