coverage run's "source" can be a path or a module.

coverage xml pretends it's a path, so we need to give a path that
exists on the file system for <sources> to be set.

.tox-coveragerc

@@ -2,10 +2,11 @@
 branch = True
 source =
     hyperlink
+    ../hyperlink
 
 [paths]
 source =
    ../hyperlink
    */lib/python*/site-packages/hyperlink
    */Lib/site-packages/hyperlink
-   pypy/site-packages/hyperlink
+   */pypy/site-packages/hyperlink