Make ClassFinalizer indifferent on whether we are generating a snapshot or not.

runtime/vm/class_finalizer.h

 // 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.
 
 #ifndef VM_CLASS_FINALIZER_H_
 #define VM_CLASS_FINALIZER_H_
 
 #include "vm/allocation.h"
 #include "vm/growable_array.h"
 
 namespace dart {
 
 class AbstractType;
 class AbstractTypeArguments;
 class Class;
 class Error;
 class Function;
 class GrowableObjectArray;
 class RawAbstractType;
 class RawClass;
 class RawType;
 class Script;
 class Type;
 class UnresolvedClass;
 
 // Traverses all pending, unfinalized classes, validates and marks them as
 // finalized.
-class ClassFinalizer : public AllStatic {
+class ClassFinalizer : public ValueObject {
  public:
+  // Malformed types will not be tolerated when generating a snapshot.
   enum {
     kGeneratingSnapshot = true,

[hausner, 2012/08/22 00:15:39]

Shouldn't the constants be named for what they affect (whether or not to
tolerate malformed types)?

As usual, I find the redefinitions of true and false unhelpful in general.

[regis, 2012/08/22 02:24:26]

Agreed. Note that the enum predated this cl. Also, I could not come up with a
better name. I thought of "strict_checking", which would apply nicely to
checking malformed types, but would have the reverse meaning for checking native
resolvers, which we only do when NOT generating a snapshot. I am open to
suggestions :-)

Regarding the style, I can live without enum and with repeating the name of the
formal parameter in a comment at the call site:
class_finalizer(/* strict_checking = */ true);
But there is always a danger for the comments to become obsolete.

     kNotGeneratingSnapshot = false
   };
-
-  // Add 'interface' to 'interface_list' if it is not already in the list and
-  // return true. Also return true if 'interface' is not added, because it is
-  // not unique, i.e. it is already in the list.
-  // Return false if 'interface' conflicts with an interface already in the list
-  // with the same class, but different type arguments.
-  // In the case of a conflict, set 'conflicting' to the existing interface.
-  static bool AddInterfaceIfUnique(const GrowableObjectArray& interface_list,
-                                   const AbstractType& interface,
-                                   AbstractType* conflicting);
+  explicit ClassFinalizer(bool generating_snapshot)

[hausner, 2012/08/22 00:15:39]

cf above. I would call this parameter "tolerate_malformed_types" or something
similar.

[regis, 2012/08/22 02:24:26]

Would it be strange to check for native resolver only if !strict_checking?

+      : generating_snapshot_(generating_snapshot) { }
 
   // Modes for type resolution and finalization. The ordering is relevant.
   enum FinalizationKind {
     kIgnore,                 // Parsed type is ignored and replaced by Dynamic.
     kDoNotResolve,           // Type resolution is postponed.
     kTryResolve,             // Type resolution is attempted, but not required.
     kFinalize,               // Type resolution and type finalization are
                              // required; a malformed type is tolerated.
     kCanonicalize,           // Same as kFinalize, but with canonicalization.
     kCanonicalizeWellFormed  // Error-free resolution, finalization, and
                              // canonicalization are required; a malformed type
                              // is not tolerated.
   };
 
   // Finalize given type while parsing class cls.
   // Also canonicalize type if applicable.
-  static RawAbstractType* FinalizeType(const Class& cls,
-                                       const AbstractType& type,
-                                       FinalizationKind finalization);
+  RawAbstractType* FinalizeType(const Class& cls,
+                                const AbstractType& type,
+                                FinalizationKind finalization) const;
 
   // Replace the malformed type with Dynamic and, depending on the given type
   // finalization mode and execution mode, mark the type as malformed or report
   // a compile time error. Prepend prev_error if not null.
-  static void FinalizeMalformedType(const Error& prev_error,
-                                    const Class& cls,
-                                    const Type& type,
-                                    FinalizationKind finalization,
-                                    const char* format, ...);
+  void FinalizeMalformedType(const Error& prev_error,
+                             const Class& cls,
+                             const Type& type,
+                             FinalizationKind finalization,
+                             const char* format, ...) const;
 
-  // Return false if we still have classes pending to be finalized.
-  static bool AllClassesFinalized();
-
-  // Return whether class finalization failed.
   // The function returns true if the finalization was successful.
   // If finalization fails, an error message is set in the sticky error field
   // in the object store.
-  static bool FinalizePendingClasses() {
-    return FinalizePendingClasses(kNotGeneratingSnapshot);
-  }
-  static bool FinalizePendingClassesForSnapshotCreation() {
-    return FinalizePendingClasses(kGeneratingSnapshot);
-  }
+  // Malformed types are tolerated or not, depending on the finalizer instance.
+  bool FinalizePendingClasses() const;
 
-  // Verify that the pending classes have been properly prefinalized. This is
+  // Return false if we still have classes to be finalized.
+  static bool AllClassesFinalized();
+
+  // Convenience function finalizing all pending classes when not generating a
+  // snapshot (malformed types are tolerated).
+  // The function returns true if the finalization was successful.
+  // If finalization fails, an error message is set in the sticky error field
+  // in the object store.
+  static bool FinalizeAllClasses();
+
+  // Verify that the classes have been properly prefinalized. This is
   // needed during bootstrapping where the classes have been preloaded.
   static void VerifyBootstrapClasses();
 
  private:
-  static bool FinalizePendingClasses(bool generating_snapshot);
-  static void FinalizeClass(const Class& cls, bool generating_snapshot);
+  void FinalizeClass(const Class& cls) const;
   static bool IsSuperCycleFree(const Class& cls);
-  static bool IsAliasCycleFree(const Class& cls,
-                               GrowableArray<intptr_t>* visited);
+  bool IsAliasCycleFree(const Class& cls,
+                        GrowableArray<intptr_t>* visited) const;
   static void CheckForLegalConstClass(const Class& cls);
   static RawClass* ResolveClass(const Class& cls,
                                 const UnresolvedClass& unresolved_class);
-  static void ResolveSuperType(const Class& cls);
+  void ResolveSuperType(const Class& cls) const;
   static void ResolveFactoryClass(const Class& cls);
-  static void ResolveInterfaces(const Class& cls,
-                                GrowableArray<intptr_t>* visited);
-  static void FinalizeTypeParameters(const Class& cls);
-  static void FinalizeTypeArguments(const Class& cls,
-                                    const AbstractTypeArguments& arguments,
-                                    FinalizationKind finalization);
-  static void ResolveType(const Class& cls,
-                          const AbstractType& type,
-                          FinalizationKind finalization);
-  static void ResolveAndFinalizeUpperBounds(const Class& cls);
-  static void ResolveAndFinalizeSignature(const Class& cls,
-                                          const Function& function);
-  static void ResolveAndFinalizeMemberTypes(const Class& cls);
+  void ResolveInterfaces(const Class& cls,
+                         GrowableArray<intptr_t>* visited) const;
+  void FinalizeTypeParameters(const Class& cls) const;
+  void FinalizeTypeArguments(const Class& cls,
+                             const AbstractTypeArguments& arguments,
+                             FinalizationKind finalization) const;
+  void ResolveType(const Class& cls,
+                   const AbstractType& type,
+                   FinalizationKind finalization) const;
+  void ResolveAndFinalizeUpperBounds(const Class& cls) const;
+  void ResolveAndFinalizeSignature(const Class& cls,
+                                   const Function& function) const;
+  void ResolveAndFinalizeMemberTypes(const Class& cls) const;
   static void PrintClassInformation(const Class& cls);
-  static void VerifyClassImplements(const Class& cls);
   static void CollectInterfaces(const Class& cls,
                                 const GrowableObjectArray& interfaces);
   static void ReportError(const Error& error);
   static void ReportError(const Script& script,
                           intptr_t token_index,
                           const char* format, ...);
   static void ReportError(const char* format, ...);
+
+  const bool generating_snapshot_;
+
+  DISALLOW_COPY_AND_ASSIGN(ClassFinalizer);
 };
 
 }  // namespace dart
 
 #endif  // VM_CLASS_FINALIZER_H_