main.cpp

#include "bimap.h"

#include "gtest/gtest.h"
#include <random>

struct test_object {
  int a = 0;
  test_object() = default;
  explicit test_object(int b) : a(b) {}
  test_object(test_object &&other) noexcept { std::swap(a, other.a); }
  friend bool operator<(test_object const &c, test_object const &b) {
    return c.a < b.a;
  }
  friend bool operator==(test_object const &c, test_object const &b) {
    return c.a == b.a;
  }
};

TEST(bimap, leak_check) {
  bimap<int, int> b;

  std::mt19937 e(std::random_device{}());
  for (size_t i = 0; i < 10000; i++) {
    b.insert(e(), e());
  }
}

TEST(bimap, simple) {
  bimap<int, int> b;
  b.insert(4, 4);
  EXPECT_EQ(b.at_right(4), b.at_left(4));
}

TEST(bimap, custom_comparator) {
  bimap<int, int, std::greater<>> b;
  b.insert(3, 4);
  b.insert(1, 5);
  b.insert(10, -10);

  int prev = *b.begin_left();
  for (auto it = ++b.begin_left(); it != b.end_left(); it++) {
    EXPECT_GT(prev, *it);
  }
  prev = *b.begin_right();
  for (auto it = ++b.begin_right(); it != b.end_right(); it++) {
    EXPECT_LT(prev, *it);
  }
}

struct vector_compare {
  using vec = std::pair<int, int>;
  enum distance_type { euclidean, manhattan };

  explicit vector_compare(distance_type p = euclidean) : type(p) {}

  bool operator()(vec a, vec b) const {
    if (type == euclidean) {
      return euc(a) < euc(b);
    } else {
      return man(a) < man(b);
    }
  }

private:
  static double euc(vec x) {
    return sqrt(x.first * x.first + x.second * x.second);
  }

  static double man(vec x) { return abs(x.first) + abs(x.second); }

  distance_type type;
};

TEST(bimap, custom_parametrized_comparator) {
  using vec = std::pair<int, int>;
  bimap<vec, vec, vector_compare, vector_compare> b(
      (vector_compare(vector_compare::manhattan)));
  b.insert({0, 1}, {35, 3});
  b.insert({20, -20}, {20, -20});
  b.insert({35, 3}, {3, -1});
  b.insert({3, -1}, {0, 1});

  std::vector<vec> correct_left = {{0, 1}, {3, -1}, {35, 3}, {20, -20}};
  std::vector<vec> correct_right = {{0, 1}, {3, -1}, {20, -20}, {35, 3}};
  auto lit = b.begin_left();
  auto rit = b.begin_right();
  for (int i = 0; i < 4; i++) {
    EXPECT_EQ(*lit++, correct_left[i]);
    EXPECT_EQ(*rit++, correct_right[i]);
  }
}

TEST(bimap, copies) {
  bimap<int, int> b;
  b.insert(3, 4);
  bimap<int, int> b1(b);
  EXPECT_EQ(*b.find_left(3).flip(), 4);
  b1.insert(4, 5);
  EXPECT_EQ(b.find_left(4), b.end_left());

  b1.insert(10, -10);
  b = b1;
  EXPECT_NE(b.find_right(-10), b.end_right());
}

TEST(bimap, insert) {
  bimap<int, int> b;
  b.insert(4, 10);
  b.insert(10, 4);
  EXPECT_EQ(*b.find_right(4).flip(), 10);
  EXPECT_EQ(b.at_left(10), 4);
}

TEST(bimap, insert_move) {
  bimap<int, test_object> b;
  test_object x(3), x2(3);
  b.insert(4, std::move(x));
  EXPECT_EQ(x.a, 0);
  EXPECT_EQ(b.at_right(x2), 4);
  EXPECT_EQ(b.at_left(4), x2);

  bimap<test_object, int> b2;
  test_object y(4), y2(4);
  b2.insert(std::move(y), 3);
  EXPECT_EQ(y.a, 0);
  EXPECT_EQ(b2.at_left(y2), 3);
  EXPECT_EQ(b2.at_right(3), y2);
}

TEST(bimap, at) {
  bimap<int, int> b;
  b.insert(4, 3);

  EXPECT_THROW(b.at_left(1), std::out_of_range);
  EXPECT_THROW(b.at_right(300), std::out_of_range);
  EXPECT_EQ(b.at_left(4), 3);
  EXPECT_EQ(b.at_right(3), 4);
}

TEST(bimap, at_or_default) {
  bimap<int, int> b;
  b.insert(4, 2);

  EXPECT_EQ(b.at_left_or_default(5), 0);
  EXPECT_EQ(b.at_right(0), 5);

  EXPECT_EQ(b.at_right_or_default(1), 0);
  EXPECT_EQ(b.at_left(0), 1);

  // b has (5, 0)
  EXPECT_EQ(b.at_left_or_default(42), 0);
  // (5, 0) is replaced with (42, 0)
  EXPECT_EQ(b.at_right(0), 42);

  // b has (0, 1)
  EXPECT_EQ(b.at_right_or_default(1000), 0);
  // (0, 1) is replaced with (0, 1000)
  EXPECT_EQ(b.at_left(0), 1000);
}

TEST(bimap, find) {
  bimap<int, int> b;
  b.insert(3, 4);
  b.insert(4, 5);
  b.insert(42, 1000);

  EXPECT_EQ(*b.find_right(5).flip(), 4);
  EXPECT_EQ(*b.find_left(3).flip(), 4);
  EXPECT_EQ(b.find_left(3436), b.end_left());
  EXPECT_EQ(b.find_right(-1000), b.end_right());
}

TEST(bimap, empty) {
  bimap<int, int> b;
  EXPECT_TRUE(b.empty());
  b.insert(1, 1);
  EXPECT_FALSE(b.empty());
}

TEST(bimap, insert_exist) {
  bimap<int, int> b;
  b.insert(1, 2);
  b.insert(2, 3);
  b.insert(3, 4);
  EXPECT_EQ(b.size(), 3);
  auto it = b.insert(2, -1);
  EXPECT_EQ(it, b.end_left());
  EXPECT_EQ(b.size(), 3);
}

TEST(bimap, erase_iterator) {
  bimap<int, int> b;
  auto it = b.insert(1, 2);
  b.insert(5, 10);
  b.insert(100, 200);
  auto it1 = b.erase_left(it);
  EXPECT_EQ(b.size(), 2);
  EXPECT_EQ(*it1, 5);

  it = b.insert(-1, -2);
  auto itr = b.erase_right(it.flip());
  EXPECT_EQ(b.size(), 2);
  EXPECT_EQ(*itr, 10);
}

TEST(bimap, erase_value) {
  bimap<int, int> b;

  b.insert(111, 222);
  b.insert(333, 444);
  EXPECT_TRUE(b.erase_left(111));
  EXPECT_EQ(b.size(), 1);
  EXPECT_FALSE(b.erase_right(333333));
  EXPECT_EQ(b.size(), 1);
}

TEST(bimap, erase_range) {
  bimap<int, int> b;

  b.insert(1, 2);
  auto f = b.insert(2, 3);
  b.insert(3, 4);
  auto l = b.insert(4, 5);
  b.insert(5, 6);

  auto it = b.erase_left(f, l);
  EXPECT_EQ(*it, 4);
  EXPECT_EQ(b.size(), 3);

  auto f1 = b.insert(100, 4).flip();
  auto l1 = b.insert(200, 10).flip();

  auto it1 = b.erase_right(f1, l1);
  EXPECT_EQ(*it1, 10);
  EXPECT_EQ(b.size(), 2);

  b.erase_left(b.begin_left(), b.end_left());
  EXPECT_TRUE(b.empty());
}

TEST(bimap, lower_bound) {
  bimap<int, int> b;

  std::vector<std::pair<int, int>> data = {
      {1, 2}, {2, 3}, {3, 4}, {8, 16}, {32, 66}};

  std::shuffle(data.begin(), data.end(), std::random_device{});
  for (auto const &p : data) {
    b.insert(p.first, p.second);
  }

  EXPECT_EQ(*b.lower_bound_left(5), 8);
  EXPECT_EQ(*b.lower_bound_right(4), 4);
  EXPECT_EQ(*b.lower_bound_left(4).flip(), 16);
  EXPECT_EQ(b.lower_bound_right(100), b.end_right());
  EXPECT_EQ(b.lower_bound_left(100), b.end_left());
}

TEST(bimap, upper_bound) {
  bimap<int, int> b;

  std::vector<std::pair<int, int>> data = {
      {1, 2}, {2, 3}, {3, 4}, {8, 16}, {32, 66}};

  std::shuffle(data.begin(), data.end(), std::random_device{});
  for (auto const &p : data) {
    b.insert(p.first, p.second);
  }

  EXPECT_EQ(*b.upper_bound_left(5), 8);
  EXPECT_EQ(*b.upper_bound_right(-100), 2);
  EXPECT_EQ(b.upper_bound_right(100), b.end_right());
  EXPECT_EQ(b.upper_bound_left(400), b.end_left());
}

template <typename T>
std::vector<std::pair<T, T>>
eliminate_same(std::vector<T> &lefts, std::vector<T> &rights, std::mt19937 &e) {
  // std::sort(lefts.begin(), lefts.end());
  auto last = std::unique(lefts.begin(), lefts.end());
  lefts.erase(last, lefts.end());
  last = std::unique(rights.begin(), rights.end());
  rights.erase(last, rights.end());

  size_t min = std::min(lefts.size(), rights.size());
  lefts.resize(min);
  rights.resize(min);

  std::shuffle(lefts.begin(), lefts.end(), e);
  std::shuffle(rights.begin(), rights.end(), e);

  std::vector<std::pair<T, T>> res(min);
  for (size_t i = 0; i < min; i++) {
    res[i] = {lefts[i], rights[i]};
  }

  return res;
}

static constexpr uint32_t seed = 1488228;

TEST(bimap_randomized, comparison) {
  std::cout << "Seed used for randomized compare test is " << seed << std::endl;

  bimap<uint32_t, uint32_t> b1;
  bimap<uint32_t, uint32_t> b2;

  size_t total = 40000;
  std::mt19937 e(seed);
  std::vector<uint32_t> lefts(total), rights(total);
  for (size_t i = 0; i < total; i++) {
    lefts[i] = e();
    rights[i] = e();
  }
  auto future_insertions = eliminate_same(lefts, rights, e);

  std::shuffle(future_insertions.begin(), future_insertions.end(), e);
  for (auto p : future_insertions) {
    b1.insert(p.first, p.second);
  }

  std::shuffle(future_insertions.begin(), future_insertions.end(), e);
  for (auto p : future_insertions) {
    b2.insert(p.first, p.second);
  }

  EXPECT_EQ(b1.size(), b2.size());
  EXPECT_EQ(b1, b2);
}

TEST(bimap_randomized, invariant_check) {
  std::cout << "Seed used for randomized invariant test is " << seed
            << std::endl;
  bimap<int, int> b;

  std::mt19937 e(seed);
  size_t ins = 0, skip = 0, total = 50000;
  for (size_t i = 0; i < total; i++) {
    auto op = e() % 10;
    if (op > 2) {
      ins++;
      b.insert(e(), e());
    } else {
      if (b.empty()) {
        skip++;
        continue;
      }
      auto it = b.end_left();
      while (it == b.end_left()) {
        it = b.lower_bound_left(e());
      }
      b.erase_left(it);
    }
    if (i % 100 == 0) {
      int previous = *b.begin_left();
      for (auto it = ++b.begin_left(); it != b.end_left(); it++) {
        EXPECT_GT(*it, previous);
        previous = *it;
      }
      previous = *b.begin_right();
      for (auto it = ++b.begin_right(); it != b.end_right(); it++) {
        EXPECT_GT(*it, previous);
        previous = *it;
      }
    }
  }
  std::cout << "Invariant check stats:" << std::endl;
  std::cout << "Performed " << ins << " insertions and " << total - ins - skip
            << " erasures. " << skip << " skipped." << std::endl;
}

TEST(bimap_randomized, compare_to_two_maps) {
  std::cout << "Seed used for randomized cmp2map test is " << seed << std::endl;

  bimap<int, int> b;
  std::map<int, int> left_view, right_view;

  std::mt19937 e(seed);
  size_t ins = 0, skip = 0, total = 60000;
  for (size_t i = 0; i < total; i++) {
    unsigned int op = e() % 10;
    if (op > 2) {
      ins++;
      // insertion
      int l = e(), r = e();
      b.insert(l, r);
      left_view.insert({l, r});
      right_view.insert({r, l});
    } else {
      // erasure
      if (b.empty()) {
        skip++;
        continue;
      }
      auto it = b.end_left();
      while (it == b.end_left()) {
        it = b.lower_bound_left(e());
      }
      EXPECT_EQ(left_view.erase(*it), 1);
      EXPECT_EQ(right_view.erase(*it.flip()), 1);
      b.erase_left(it);
    }
    if (i % 100 == 0) {
      // check
      EXPECT_EQ(b.size(), left_view.size());
      EXPECT_EQ(b.size(), right_view.size());
      auto lit = b.begin_left();
      auto mlit = left_view.begin();
      for (; lit != b.end_left() && mlit != left_view.end(); lit++, mlit++) {
        EXPECT_EQ(*lit, mlit->first);
        EXPECT_EQ(*lit.flip(), mlit->second);
      }
    }
  }
  std::cout << "Comparing to maps stat:" << std::endl;
  std::cout << "Performed " << ins << " insertions and " << total - ins - skip
            << " erasures. " << skip << " skipped." << std::endl;
}