Commit a308b435 authored by Committed by Marge Bot
The `mkOneConFull` function of the pattern match checker used to try to guess the type arguments of the data type's type constructor by looking at the ambient type of the match. This doesn't work well for Pattern Synonyms, where the result type isn't even necessarily a TyCon application, and it shows in #11336 and #17112. Also the effort seems futile; why try to try hard when the type checker has already done the hard lifting? After this patch, we instead supply the type constructors arguments as an argument to the function and lean on the type-annotated AST.
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