Merge pull request #60734 from tshortli/check-func-param-result-builder-availability

Sema: Check the availability of result builder attributes on function parameters

Author: tshortli

lib/Sema/TypeCheckAccess.cpp

@@ -1868,6 +1868,9 @@ class DeclAvailabilityChecker : public DeclVisitor<DeclAvailabilityChecker> {
         checkType(wrapperType, wrapperAttrs[index]->getTypeRepr(), fn);
       }
 
+      if (auto attr = P->getAttachedResultBuilder())
+        checkType(P->getResultBuilderType(), attr->getTypeRepr(), fn);
+
       checkType(P->getInterfaceType(), P->getTypeRepr(), fn);
     }
   }

test/Constraints/result_builder_availability.swift

@@ -5,13 +5,16 @@
 @available(*, unavailable)
 @resultBuilder
 struct UnavailableBuilder {
-// expected-note@-1 {{'UnavailableBuilder' has been explicitly marked unavailable here}}
+// expected-note@-1 2 {{'UnavailableBuilder' has been explicitly marked unavailable here}}
   static func buildBlock() {}
 }
 
 @UnavailableBuilder public func usesUnavailableBuilder() {}
 // expected-error@-1 {{'UnavailableBuilder' is unavailable}}
 
+public func takesUnavailableBuilder(@UnavailableBuilder _ fn: () -> ()) {}
+// expected-error@-1 {{'UnavailableBuilder' is unavailable}}
+
 enum Either<T,U> {
   case first(T)
   case second(U)