I asked the trivia question "Which two Tim Burton-directed films did Danny Elfman not score?" Polly Pospisil, a local trivia contest quizmaster whose games I've attended, got one answer (Ed Wood), but wasn't sure of the second (Sweeney Todd):
Her: Wasn't it some war movie he directed?
Me: No, not a war film. Unless it was a WAR ON NECKS. USING KNIVES. (Whoa. Channeling @FatboyRoberts & @CortWebber there...)
Elfman didn't score Ed Wood because he and Burton were on the outs by the time Burton shot it, though in at least one 1994 interview Elfman claimed he was going to score it. Howard Shore, who at the time had the same agent as Elfman, got the job and scored it admirably. Elfman and Burton patched things up and became friends again during filming of Mars Attacks!, and the story I've heard is that late in that film's production, Burton personally asked Shore if he'd step aside from Mars Attacks! so Elfman could score it.
And Sweeney Todd was already fully scored, of course, by Stephen Sondheim.