Tests should cover public etntrypoints only. 100% coverage is fanatic and people who advocate it are overdue for a vacation or maybe mental institutionalization. Anyone who would change a private function to publica to make it “testable” has lost his way.
And anyone who talks about “refactoring” for “testability” is someone I don’t want to hear from, much less work with. Buzzword bullshit, meaning nothing.
I don’t like unit tests, they’re too much work and yield too little value. What tests I do write are for public entrypoints only since any failure will lead to investigation.
There is way too much talk about testing and not enough about coding.