I don't want there to be an edit/build/test cycle - I want my tests to be validated continuously. I want my IDE to point out instantly that I have made a change

I don't want there to be an edit/build/test cycle - I want my tests to be validated continuously. I want my IDE to point out instantly that I have made a change that breaks 3 of my 10 unit tests, and I want a panel that shows exactly what the output used to be for each test, and what it is now.