/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions
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 * 1.  Redistributions of source code must retain the above copyright
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// Tests for the red-black tree class.

#include "platform/PODRedBlackTree.h"

#include "platform/testing/ArenaTestHelpers.h"
#include "platform/testing/TreeTestHelpers.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "wtf/Vector.h"

namespace blink {

using ArenaTestHelpers::TrackedAllocator;
using TreeTestHelpers::initRandom;
using TreeTestHelpers::nextRandom;

TEST(PODRedBlackTreeTest, TestTreeAllocatesFromArena) {
  RefPtr<TrackedAllocator> allocator = TrackedAllocator::create();
  {
    typedef PODFreeListArena<PODRedBlackTree<int>::Node> PODIntegerArena;
    RefPtr<PODIntegerArena> arena = PODIntegerArena::create(allocator);
    PODRedBlackTree<int> tree(arena);
    int numAdditions = 2 * PODArena::DefaultChunkSize / sizeof(int);
    for (int i = 0; i < numAdditions; ++i)
      tree.add(i);
    EXPECT_GT(allocator->numRegions(), 1);
  }
  EXPECT_EQ(allocator->numRegions(), 0);
}

TEST(PODRedBlackTreeTest, TestSingleElementInsertion) {
  PODRedBlackTree<int> tree;
  tree.add(5);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(5));
}

TEST(PODRedBlackTreeTest, TestMultipleElementInsertion) {
  PODRedBlackTree<int> tree;
  tree.add(4);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(4));
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(3));
  tree.add(5);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(5));
  EXPECT_TRUE(tree.contains(4));
  EXPECT_TRUE(tree.contains(3));
}

TEST(PODRedBlackTreeTest, TestDuplicateElementInsertion) {
  PODRedBlackTree<int> tree;
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_EQ(3, tree.size());
  EXPECT_TRUE(tree.contains(3));
}

TEST(PODRedBlackTreeTest, TestSingleElementInsertionAndDeletion) {
  PODRedBlackTree<int> tree;
  tree.add(5);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(5));
  tree.remove(5);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_FALSE(tree.contains(5));
}

TEST(PODRedBlackTreeTest, TestMultipleElementInsertionAndDeletion) {
  PODRedBlackTree<int> tree;
  tree.add(4);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(4));
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(3));
  tree.add(5);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(5));
  EXPECT_TRUE(tree.contains(4));
  EXPECT_TRUE(tree.contains(3));
  tree.remove(4);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(3));
  EXPECT_FALSE(tree.contains(4));
  EXPECT_TRUE(tree.contains(5));
  tree.remove(5);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_TRUE(tree.contains(3));
  EXPECT_FALSE(tree.contains(4));
  EXPECT_FALSE(tree.contains(5));
  EXPECT_EQ(1, tree.size());
}

TEST(PODRedBlackTreeTest, TestDuplicateElementInsertionAndDeletion) {
  PODRedBlackTree<int> tree;
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(3);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_EQ(3, tree.size());
  EXPECT_TRUE(tree.contains(3));
  tree.remove(3);
  ASSERT_TRUE(tree.checkInvariants());
  tree.remove(3);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_EQ(1, tree.size());
  EXPECT_TRUE(tree.contains(3));
  tree.remove(3);
  ASSERT_TRUE(tree.checkInvariants());
  EXPECT_EQ(0, tree.size());
  EXPECT_FALSE(tree.contains(3));
}

TEST(PODRedBlackTreeTest, FailingInsertionRegressionTest1) {
  // These numbers came from a previously-failing randomized test run.
  PODRedBlackTree<int> tree;
  tree.add(5113);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(4517);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(3373);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(9307);
  ASSERT_TRUE(tree.checkInvariants());
  tree.add(7077);
  ASSERT_TRUE(tree.checkInvariants());
}

namespace {
void InsertionAndDeletionTest(const int32_t seed, const int treeSize) {
  initRandom(seed);
  const int maximumValue = treeSize;
  // Build the tree.
  PODRedBlackTree<int> tree;
  Vector<int> values;
  for (int i = 0; i < treeSize; i++) {
    int value = nextRandom(maximumValue);
    tree.add(value);
    ASSERT_TRUE(tree.checkInvariants()) << "Test failed for seed " << seed;
    values.append(value);
  }
  // Churn the tree's contents.
  for (int i = 0; i < treeSize; i++) {
    // Pick a random value to remove.
    int index = nextRandom(treeSize);
    int value = values[index];
    // Remove this value.
    tree.remove(value);
    ASSERT_TRUE(tree.checkInvariants()) << "Test failed for seed " << seed;
    // Replace it with a new one.
    value = nextRandom(maximumValue);
    values[index] = value;
    tree.add(value);
    ASSERT_TRUE(tree.checkInvariants()) << "Test failed for seed " << seed;
  }
}
}  // anonymous namespace

TEST(PODRedBlackTreeTest, RandomDeletionAndInsertionRegressionTest1) {
  InsertionAndDeletionTest(12311, 100);
}

}  // namespace blink