// 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.

#include "platform/assert.h"
#include "vm/scavenger.h"
#include "vm/unit_test.h"
#include "vm/visitor.h"

namespace dart {

// Expects to visit no objects (since the space should be empty).
class FailingObjectVisitor : public ObjectVisitor {
 public:
  FailingObjectVisitor() : ObjectVisitor(NULL) {}
  virtual void VisitObject(RawObject* obj) {
    EXPECT(false);
  }
};

// Expects to visit no objects (since the space should be empty).
class FailingObjectPointerVisitor : public ObjectPointerVisitor {
 public:
  FailingObjectPointerVisitor() : ObjectPointerVisitor(NULL) {}
  virtual void VisitPointers(RawObject** first, RawObject** last) {
    EXPECT(false);
  }
};

// Expects to visit no objects (since the space should be empty).
class FailingFindObjectVisitor : public FindObjectVisitor {
 public:
  FailingFindObjectVisitor() : FindObjectVisitor(NULL) {}
  virtual bool FindObject(RawObject* obj) const {
    EXPECT(false);
    return false;
  }
};

TEST_CASE(ZeroSizeScavenger) {
  Scavenger* scavenger = new Scavenger(NULL, 0, kNewObjectAlignmentOffset);
  EXPECT(!scavenger->Contains(reinterpret_cast<uword>(&scavenger)));
  EXPECT_EQ(0, scavenger->UsedInWords());
  EXPECT_EQ(0, scavenger->CapacityInWords());
  EXPECT_EQ(static_cast<uword>(0), scavenger->TryAllocate(kObjectAlignment));
  FailingObjectVisitor obj_visitor;
  scavenger->VisitObjects(&obj_visitor);
  FailingObjectPointerVisitor ptr_visitor;
  scavenger->VisitObjectPointers(&ptr_visitor);
  FailingFindObjectVisitor find_visitor;
  scavenger->FindObject(&find_visitor);
  delete scavenger;
}

TEST_CASE(ZeroSizeScavengerGC) {
  // Ensure 'Scavenge' doesn't crash. We must supply an actual heap.
  Scavenger* scavenger =
      new Scavenger(Isolate::Current()->heap(), 0, kNewObjectAlignmentOffset);
  scavenger->Scavenge();
  delete scavenger;
}

}  // namespace dart