Make TypeSystem.resolveToBound() do what it promised in the documentation.

scheglov · commit-bot@chromium.org · commit 7d5432465735 · 2019-08-07T22:41:15.000Z
OTOH, we don't have TypeSystem.instantiateToBounds(), so I'm not 100% sure whether the doc is inaccurate, or instantiateToBounds() should be added. Or even if DartType.resolveToBound() should be used, not the version from TypeSystem. R=brianwilkerson@google.com, paulberry@google.com Change-Id: Ied333161d68af40314f4b8e2c3cee3b350d05f7c Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/110757 Reviewed-by: Brian Wilkerson <brianwilkerson@google.com> Reviewed-by: Paul Berry <paulberry@google.com> Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
diff --git a/pkg/analyzer/lib/src/generated/type_system.dart b/pkg/analyzer/lib/src/generated/type_system.dart
@@ -2633,7 +2633,31 @@ abstract class TypeSystem implements public.TypeSystem {
 
   @override
   DartType resolveToBound(DartType type) {
-    return instantiateToBounds(type);
+    if (type is TypeParameterTypeImpl) {
+      var element = type.element;
+
+      var bound = element.bound as TypeImpl;
+      if (bound == null) {
+        return typeProvider.objectType;
+      }
+
+      NullabilitySuffix nullabilitySuffix = type.nullabilitySuffix;
+      NullabilitySuffix newNullabilitySuffix;
+      if (nullabilitySuffix == NullabilitySuffix.question ||
+          bound.nullabilitySuffix == NullabilitySuffix.question) {
+        newNullabilitySuffix = NullabilitySuffix.question;
+      } else if (nullabilitySuffix == NullabilitySuffix.star ||
+          bound.nullabilitySuffix == NullabilitySuffix.star) {
+        newNullabilitySuffix = NullabilitySuffix.star;
+      } else {
+        newNullabilitySuffix = NullabilitySuffix.none;
+      }
+
+      var resolved = resolveToBound(bound) as TypeImpl;
+      return resolved.withNullability(newNullabilitySuffix);
+    }
+
+    return type;
   }
 
   /**
