Generate with carefully steered AI, sanity check carefully. For a big enough project writing actually comprehensive test coverage completely by hand could be months of work.
Even state of the art AI models seem to have no taste, or sense of 'hang on, what's even the point of this test' so I've seen them diligently write hundreds of completely pointless tests and sometimes the reason they're pointless is some subtle thing that's hard to notice amongst all the legit looking expect code.
Even state of the art AI models seem to have no taste, or sense of 'hang on, what's even the point of this test' so I've seen them diligently write hundreds of completely pointless tests and sometimes the reason they're pointless is some subtle thing that's hard to notice amongst all the legit looking expect code.