Current Salary - sure, go ahead and hide. But expected salary imo if the company asks, then you should give. From an employer perspective, especially for junior-level hires, this would give me an up front indication of whether your salary expectations are within what I'm looking to pay. If your expectation higher than what I think you're worth, then we don't need to waste time going through interview and all that, no?

for what it's worth, it's typically HR who causing all this trouble. When I wanna hire a person I don't care what his last drawn salary is. But HR will campur tangan and say nono we must know what is his last drawn salary so that we can benchmark here and there and don't overpay him or whatever.