match: override 'visitdir' in subdirmatcher The manifest.manifest class has a _treeinmem member than one can manually set to True to test that the treemanifest class works as a drop-in replacement for manifestdict (which is mostly a requirement for treemanifest repos to work). However, it doesn't quite work at the moment. These tests fail: test-largefiles-misc.t test-rebase-newancestor.t test-subrepo.t test-subrepo-deep-nested-change.t test-subrepo-recursion.t All but test-rebase-newancestor.t fail because they trigger calls to subdirmatcher.visitdir(), which tries to access a _excluderoots field that does not exist on the subdirmatcher. Let's fix that by overriding visitdir() in a similar way to how matchfn is overridden, i.e. by prepending the directory before calling the superclass method.