--- a/tests/test-check-py3-commands.t Fri Mar 03 14:08:02 2017 -0500
+++ b/tests/test-check-py3-commands.t Fri Mar 03 13:52:08 2017 -0500
@@ -12,3 +12,14 @@
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
debuginstall
TypeError: Can't convert 'bytes' object to str implicitly
+
+ $ cat > included-hgrc <<EOF
+ > [extensions]
+ > babar = imaginary_elephant
+ > EOF
+ $ cat >> $HGRCPATH <<EOF
+ > %include $TESTTMP/included-hgrc
+ > EOF
+ $ $PYTHON3 `which hg` version | tail -1
+ *** failed to import extension babar from imaginary_elephant: *: 'imaginary_elephant' (glob)
+ warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.