> The user has configured color = true (so color will return true in RSpec 3)
output_stream has been configured to a non-tty.

That's a good point, I'll add that one too.

> Actually...while we technically probably should, I just realized that there's no public API available in 2.99 that provides the behavior of color on 3.0 so there's nothing to suggest the user to use instead to keep the same behavior that they are relying on. So I'm thinking we don't bother for this case since it's such an edge case anyway.

They can't be relying on the behaviour, as it's new behaviour, they can only be relying on the old behaviour, which is provided by `color_enabled?` which is why it recommends it.