Actually I've never been heavily involved in hiring a junior. Even at my own level (>26 years prof. experience) I'd happily do a test before a formal interview

Actually I've never been heavily involved in hiring a junior. Even at my own level (>26 years prof. experience) I'd happily do a test before a formal interview (though I'd likely want a brief chat with someone from the company to get a feel for what sort of shop they run first). And I would be judging the employer on the quality of their test.