diff --git a/hgext/phabricator.py b/hgext/phabricator.py
--- a/hgext/phabricator.py
+++ b/hgext/phabricator.py
@@ -671,8 +671,10 @@
     pos = 0
     length = len(text)
     while pos < length:
-        symbol = b''.join(itertools.takewhile(lambda ch: ch not in special,
-                                              view[pos:]))
+        symbol = b''.join(pycompat.iterbytestr(itertools.takewhile(
+            lambda ch: ch not in special,
+            view[pos:]
+        )))
         if symbol:
             yield (b'symbol', symbol, pos)
             pos += len(symbol)