add a failing test case to demonstrate a substitution issue

pkg/analyzer/test/generated/resolver_test.dart

 // Copyright (c) 2014, 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 engine.resolver_test;
 
 import 'dart:collection';
 
 import 'package:analyzer/src/context/context.dart' as newContext;
 import 'package:analyzer/src/generated/ast.dart';
@@ skipping 12201 matching lines @@
     expect(e.type.toString(), '(E) → List<T>');
 
     SimpleIdentifier c = _findIdentifier('cOfString');
     FunctionType ft = (c.staticType as InterfaceType).getMethod('f').type;
     expect(ft.toString(), '(String) → List<T>');
     DartType t = e.typeParameters[0].type;
     ft = ft.substitute2([typeProvider.intType], [t]);
     expect(ft.toString(), '(String) → List<int>');
   }
 
+  void fail_genericMethod_nested() {
+    // TODO(jmesserly): this test currently fails because we incorrectly capture
+    // S in FunctionTypeImpl.substitute. We should probably rename free
+    // variables during substitution to avoid it.
+    _resolveTestUnit(r'''
+class C<T> {
+  /*=T*/ f/*<S>*/(/*=S*/ x) {
+    new C<S>().f/*<int>*/(3);
+    return null;
+  }
+}
+''');
+    SimpleIdentifier f = _findIdentifier('f/*<int>*/(3);');
+    expect(f.staticType.toString(), '(int) → S');
+  }
+
   void test_genericMethod_functionTypedParameter() {
     if (!AnalysisEngine.instance.useTaskModel) {
       return;
     }
     _resolveTestUnit(r'''
 class C<E> {
   List/*<T>*/ f/*<T>*/(/*=T*/ f(E e)) => null;
 }
 main() {
   C<String> cOfString;
@@ skipping 2976 matching lines @@
 
   void _resolveTestUnit(String code) {
     testCode = code;
     testSource = addSource(testCode);
     LibraryElement library = resolve2(testSource);
     assertNoErrors(testSource);
     verify([testSource]);
     testUnit = resolveCompilationUnit(testSource, library);
   }
 }