I've done this. Told them up front what my current salary was. Tild them directly they could meet or beat it and we'd be good. Went through weeks of interviews.

They offered me a $20k per year lower salary than what I was making. Because that was their salary for my region.

I told them that was unacceptable. That I was uo front about the minimum I'd accept. They countered with a $15k paycut.

They seemed genuinely syrprised when I said no.