[analyzer] copy generic type args when inferring a new function type for an ExecutableElement

pkg/analyzer/lib/src/task/strong_mode.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library analyzer.src.task.strong_mode;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/generated/ast.dart';
 import 'package:analyzer/src/generated/element.dart';
@@ skipping 10 matching lines @@
       //
       // Update the type of the parameter.
       //
       parameter.type = type;
       //
       // Update the type of the setter to reflect the new parameter type.
       //
       FunctionType functionType = element.type;
       if (functionType is FunctionTypeImpl) {
         element.type =
-            new FunctionTypeImpl(element, functionType.prunedTypedefs);
+            new FunctionTypeImpl(element, functionType.prunedTypedefs)
+              ..typeArguments = functionType.typeArguments;

[Jennifer Messerly, 2015/09/24 22:35:56]

not sure if y'all use cascades, let me know if there's a better way to format
this.

[Brian Wilkerson, 2015/09/24 22:49:27]

I haven't gotten in the habit of using them much, but don't have a problem with
them being used. As for formatting, we always run the formatter over everything
so that formatting is never a question.

       } else {
         assert(false);
       }
     } else {
       assert(false);
     }
   } else {
     throw new StateError('element is an instance of ${element.runtimeType}');
     assert(false);
   }
 }
 
 /**
  * Set the return type of the given [element] to the given [type].
  */
 void setReturnType(ExecutableElement element, DartType type) {
   if (element is ExecutableElementImpl) {
     //
     // Update the return type of the element, which is stored in two places:
     // directly in the element and indirectly in the type of the element.
     //
     element.returnType = type;
     FunctionType functionType = element.type;
     if (functionType is FunctionTypeImpl) {
-      element.type = new FunctionTypeImpl(element, functionType.prunedTypedefs);
+      element.type = new FunctionTypeImpl(element, functionType.prunedTypedefs)
+        ..typeArguments = functionType.typeArguments;
     } else {
       assert(false);
     }
   } else {
     assert(false);
   }
 }
 
 /**
  * Return the element for the single parameter of the given [setter], or `null`
@@ skipping 403 matching lines @@
         results.add(element);
       }
     }
   }
 }
 
 /**
  * A class of exception that is not used anywhere else.
  */
 class _CycleException implements Exception {}