Steps to reproduce the issue

1. Clone this repo and change to the branch 4.0.-dev
2. run composer i

Expected result

No warnings or abandoned messages.

Actual result

I see this message

Loading composer repositories with package information
Installing dependencies (including require-dev) from lock file
Package operations: 29 installs, 0 updates, 0 removals
...
Package phpunit/phpunit-mock-objects is abandoned, you should avoid using it. No replacement was suggested.
Package phpunit/dbunit is abandoned, you should avoid using it. No replacement was suggested.

System information (as much as possible)

composer --version
Composer version 1.9.1 2019-11-01 17:20:17

Additional comments