diff --git a/tests/test-install.t b/tests/test-install.t
--- a/tests/test-install.t
+++ b/tests/test-install.t
@@ -250,6 +250,7 @@
 Note: we use this weird path to run pip and hg to avoid platform differences,
 since it's bin on most platforms but Scripts on Windows.
   $ ./installenv/*/pip install --no-index $TESTDIR/.. >> pip.log
+    Failed building wheel for mercurial (?)
   $ ./installenv/*/hg debuginstall || cat pip.log
   checking encoding (ascii)...
   checking Python executable (*) (glob)