From the doc comments for Main, MainStart is preferred:
Systems simulating "go test" should be updated to use MainStart.
Previously, before go1.18, the internal interface testDeps could be satisfied by an external package. Upgrading to go1.18 the new internal interface contains methods with references to a private struct corpusEntry for the added fuzzing support. MainStart isn't part of the go compatibility promise. I propose providing an implementation of testDeps like