[test] test generic params with implicit some

Author: angela-laar

test/type/implicit_some/opaque_parameters.swift

@@ -62,10 +62,9 @@ func consumingA(fn: (P) -> Void) { } // expected-error{{'some' cannot appear in
 func consumingB(fn: FnType<P>) { } // expected-error{{'some' cannot appear in parameter position in parameter type '(P) -> Void'}}
 
 
-// TO-DO Handle plain generic opaque parameters
 func takePrimaryCollections(
-  _ strings:some Collection<String>,
-  _ ints : some Collection<Int>
+  _ strings: Collection<String>,
+  _ ints : Collection<Int>
 ) {
   for s in strings {
     let _: String = s
@@ -75,9 +74,8 @@ func takePrimaryCollections(
     let _: Int = i
   }
 }
-// TO-DO Handle plain generic opaque parameters
 func takeMatchedPrimaryCollections<T: Equatable>(
-  _ first: some Collection<T>, _ second: some Collection<T>
+  _ first: Collection<T>, _ second: Collection<T>
 ) -> Bool {
   first.elementsEqual(second)
 }

test/type/implicit_some/opaque_return.swift

@@ -125,3 +125,14 @@ enum E {
 protocol Q {
     func f() -> Int
 }
+
+func findBiggerCollection<T : Numeric>( _ first: Collection<T>, _ second: Collection<T>) -> Collection<T> {
+  // expected-error@-1 {{function declares an opaque return type 'Collection<T>', but the return statements in its body do not have matching underlying types}}
+  if (first.count > second.count) { return first } //expected-note {{return statement has underlying type 'Collection<T>'}}
+  return second //expected-note {{return statement has underlying type 'Collection<T>'}}
+}
+
+func createCollection() -> Collection<Int> {
+  let a = [9,2,0]
+  return a
+}