Convert unit tests to the new message-passing API
Upstream changes force this update. The private API is now getting
more and more private.
Merge branch 'api-change'
daa62fb1cfdfc1a3fb594980c8c3c014f37dda7d
by Linas Vepštas <linasvepstas@gmail.com> · 2026-01-19T00:48:01.000Z