diff -r 2cd5f1fac788 -r c93d046d4300 tests/blackbox-readonly-dispatch.py
--- a/tests/blackbox-readonly-dispatch.py	Sat Nov 17 19:11:45 2018 +0900
+++ b/tests/blackbox-readonly-dispatch.py	Mon Nov 12 21:10:51 2018 +0900
@@ -2,6 +2,7 @@
 import os
 from mercurial import (
     dispatch,
+    extensions,
     ui as uimod,
 )
 
@@ -11,6 +12,7 @@
     Prints command and result value, but does not handle quoting.
     """
     ui = uimod.ui.load()
+    extensions.populateui(ui)
     ui.status(b"running: %s\n" % cmd)
     req = dispatch.request(cmd.split(), ui)
     result = dispatch.dispatch(req)