What I meant to say is that I don't want to change the assertions on existing tests that check for output like `system (set by ${RBENV_ROOT}/version)`. There are 4 such changes in this PR, but I want to avoid them. I'd rather change the tests setup 4 times to explicitly provide a global version file, and leave the assertions intact.

Then I would add new tests that explicitly verify that there is *no* global version file, and write new assertions for those tests.