Refactor resolution code in the vm to properly handle ambiguity errors.

runtime/vm/resolver_test.cc

 // Copyright (c) 2012, 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.
 
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler.h"
 #include "vm/dart_entry.h"
 #include "vm/object.h"
@@ skipping 74 matching lines @@
   SetupStaticFunction(test_library_name,
                       test_class_name,
                       test_static_function_name);
 
   const String& library_name = String::Handle(String::New(test_library_name));
   const Library& library =
       Library::Handle(Library::LookupLibrary(library_name));
   const String& class_name = String::Handle(String::New(test_class_name));
   const String& static_function_name =
       String::Handle(String::New(test_static_function_name));
+  String& ambiguity_error_msg = String::Handle();
 
   // Now try to resolve and invoke the static function in this class.
   {
     const int kNumArguments = 2;
     const Function& function = Function::Handle(
         Resolver::ResolveStatic(library,
                                 class_name,
                                 static_function_name,
                                 kNumArguments,
                                 Object::empty_array(),
-                                kResolveType));
-    EXPECT(!function.IsNull());
+                                kResolveType,
+                                &ambiguity_error_msg));
+    EXPECT(!function.IsNull());  // No ambiguity error expected.
     const Array& args = Array::Handle(Array::New(kNumArguments));
     const String& arg0 = String::Handle(String::New("junk"));
     args.SetAt(0, arg0);
     const Smi& arg1 = Smi::Handle(Smi::New(kTestValue));
     args.SetAt(1, arg1);
     const Smi& retval = Smi::Handle(
         reinterpret_cast<RawSmi*>(DartEntry::InvokeFunction(function, args)));
     EXPECT_EQ(kTestValue, retval.Value());
   }
 
   // Now try to resolve a static function with invalid argument count.
   {
     const int kNumArguments = 1;
     const Function& bad_function = Function::Handle(
         Resolver::ResolveStatic(library,
                                 class_name,
                                 static_function_name,
                                 kNumArguments,
                                 Object::empty_array(),
-                                kResolveType));
-    EXPECT(bad_function.IsNull());
+                                kResolveType,
+                                &ambiguity_error_msg));
+    EXPECT(bad_function.IsNull());  // No ambiguity error expected.
   }
 
   // Hierarchy walking.
   {
     const String& super_static_function_name =
         String::Handle(String::New("statCall"));
     const String& super_class_name = String::Handle(String::New("Base"));
     const int kNumArguments = 0;
     const Function& super_function = Function::Handle(
         Resolver::ResolveStatic(library,
                                 super_class_name,
                                 super_static_function_name,
                                 kNumArguments,
                                 Object::empty_array(),
-                                kResolveType));
-    EXPECT(!super_function.IsNull());
+                                kResolveType,
+                                &ambiguity_error_msg));
+    EXPECT(!super_function.IsNull());  // No ambiguity error expected.
   }
 }
 
 
 TEST_CASE(DartDynamicResolve) {
   const char* test_library_name = "ResolverApp";
   const char* test_class_name = "A";
   const char* test_function_name = "foo";
   const int kTestValue = 42;
 
   // Setup a function which can be invoked.
   SetupInstanceFunction(test_library_name,
                         test_class_name,
                         test_function_name);
 
   // Now create an instance object of the class and try to
   // resolve a function in it.
   const String& lib_name = String::Handle(String::New(test_library_name));
   const Library& lib = Library::Handle(Library::LookupLibrary(lib_name));
   ASSERT(!lib.IsNull());
+  String& ambiguity_error_msg = String::Handle();
   const Class& cls = Class::Handle(lib.LookupClass(
-      String::Handle(Symbols::New(test_class_name))));
-  EXPECT(!cls.IsNull());
+      String::Handle(Symbols::New(test_class_name)), &ambiguity_error_msg));
+  EXPECT(!cls.IsNull());  // No ambiguity error expected.
 
   Instance& receiver = Instance::Handle(Instance::New(cls));
   const String& function_name = String::Handle(String::New(test_function_name));
 
   // Now try to resolve and invoke the instance function in this class.
   {
     const int kNumArguments = 3;
     ArgumentsDescriptor args_desc(
         Array::Handle(ArgumentsDescriptor::New(kNumArguments)));
     const Function& function = Function::Handle(
@@ skipping 33 matching lines @@
         String::Handle(String::New("dynCall"));
     const Function& super_function = Function::Handle(
         Resolver::ResolveDynamic(receiver,
                                  super_function_name,
                                  args_desc));
     EXPECT(!super_function.IsNull());
   }
 }
 
 }  // namespace dart