https://www.loudersound.com/features/purple-rain-by-prince-the-story-behind-the-song
This is simply not true: "On August 3, 1983, Prince and the Revolution broke off from filming Purple Rain and recording its soundtrack album" https://www.loudersound.com/features/purple-rain-by-prince-the-story-behind-the-song … . Duane Tudahl just wrote an entire book that meticulously details this period, why not check that?
Or simply check http://princevault.com/index.php?title=Album:_Purple_Rain … and http://princevault.com/index.php?title=Film:_Purple_Rain … . I mean: "Shooting started on 1 November 1983 in Minneapolis." And apart from "Darling Nikki", not a single track was recorded before 3 August 1983 (except from some raw demos or rehearsal recordings).
This isn't some obscure album, this is a landmark album whose recording process has been documented in great detail by various experts. Why then write absolute nonsense? Why not ask an expert? Why not do some basic research?