Fix wrong canonicalization of signature class due to name collision (issue 6353).

runtime/vm/object.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 "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/bigint_operations.h"
@@ skipping 3903 matching lines @@
 
 RawString* Function::BuildSignature(
     bool instantiate,
     NameVisibility name_visibility,
     const AbstractTypeArguments& instantiator) const {
   const GrowableObjectArray& pieces =
       GrowableObjectArray::Handle(GrowableObjectArray::New());
   const String& kCommaSpace = String::Handle(Symbols::New(", "));
   const String& kColonSpace = String::Handle(Symbols::New(": "));
   const String& kLParen = String::Handle(Symbols::New("("));
-  const String& kRParen = String::Handle(Symbols::New(") => "));
+  const String& kRParenArrow = String::Handle(Symbols::New(") => "));
   const String& kLBracket = String::Handle(Symbols::New("["));
   const String& kRBracket = String::Handle(Symbols::New("]"));
   const String& kLBrace = String::Handle(Symbols::New("{"));
   const String& kRBrace = String::Handle(Symbols::New("}"));
   String& name = String::Handle();
-  if (!instantiate && !is_static()) {
-    // Prefix the signature with its type parameters, if any (e.g. "<K, V>").
+  if (!instantiate && !is_static() && (name_visibility == kInternalName)) {
+    // Prefix the signature with its class and type parameters, if any (e.g.
+    // "Map<K, V>(K) => bool").
     // The signature of static functions cannot be type parameterized.
     const String& kSpaceExtendsSpace =
         String::Handle(Symbols::New(" extends "));
     const String& kLAngleBracket = String::Handle(Symbols::New("<"));
     const String& kRAngleBracket = String::Handle(Symbols::New(">"));
     const Class& function_class = Class::Handle(Owner());
     ASSERT(!function_class.IsNull());
     const TypeArguments& type_parameters = TypeArguments::Handle(
         function_class.type_parameters());
     if (!type_parameters.IsNull()) {
+      const String& function_class_name = String::Handle(function_class.Name());
+      pieces.Add(function_class_name);
       intptr_t num_type_parameters = type_parameters.Length();
       pieces.Add(kLAngleBracket);
       TypeParameter& type_parameter = TypeParameter::Handle();
       AbstractType& bound = AbstractType::Handle();
       for (intptr_t i = 0; i < num_type_parameters; i++) {
         type_parameter ^= type_parameters.TypeAt(i);
         name = type_parameter.name();
         pieces.Add(name);
         bound = type_parameter.bound();
-        if (!bound.IsNull() && !bound.IsDynamicType()) {
+        if (!bound.IsNull() && !bound.IsObjectType()) {
           pieces.Add(kSpaceExtendsSpace);
           name = bound.BuildName(name_visibility);
           pieces.Add(name);
         }
         if (i < num_type_parameters - 1) {
           pieces.Add(kCommaSpace);
         }
       }
       pieces.Add(kRAngleBracket);
     }
@@ skipping 42 matching lines @@
       if (i != (num_params - 1)) {
         pieces.Add(kCommaSpace);
       }
     }
     if (num_opt_pos_params > 0) {
       pieces.Add(kRBracket);
     } else {
       pieces.Add(kRBrace);
     }
   }
-  pieces.Add(kRParen);
+  pieces.Add(kRParenArrow);
   AbstractType& res_type = AbstractType::Handle(result_type());
   if (instantiate && !res_type.IsInstantiated()) {
     res_type = res_type.InstantiateFrom(instantiator);
   }
   name = res_type.BuildName(name_visibility);
   pieces.Add(name);
   const Array& strings = Array::Handle(Array::MakeArray(pieces));
   return Symbols::New(String::Handle(String::ConcatAll(strings)));
 }
 
@@ skipping 8130 matching lines @@
   }
   return result.raw();
 }
 
 
 const char* WeakProperty::ToCString() const {
   return "_WeakProperty";
 }
 
 }  // namespace dart