base/containers/flat_set_unittest.cc

// Copyright 2017 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/containers/flat_set.h"

#include <string>

#include "base/memory/ptr_util.h"
#include "base/test/move_only_int.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"

// A flat_set is basically a interface to flat_tree. So several basic
// operations are tested to make sure things are set up properly, but the bulk
// of the tests are in flat_tree_unittests.cc.

using ::testing::ElementsAre;

namespace base {

namespace {

class ImplicitInt {
 public:
  // NOLINTNEXTLINE(google-explicit-constructor)
  ImplicitInt(int data) : data_(data) {}

 private:
  friend bool operator<(const ImplicitInt& lhs, const ImplicitInt& rhs) {
    return lhs.data_ < rhs.data_;
  }

  int data_;
};

}  // namespace

TEST(FlatSet, IncompleteType) {
  struct A {
    using Set = flat_set<A>;
    int data;
    Set set_with_incomplete_type;
    Set::iterator it;
    Set::const_iterator cit;

    // We do not declare operator< because clang complains that it's unused.
  };

  A a;
}

TEST(FlatSet, RangeConstructor) {
  flat_set<int>::value_type input_vals[] = {1, 1, 1, 2, 2, 2, 3, 3, 3};

  flat_set<int> cont(std::begin(input_vals), std::end(input_vals));
  EXPECT_THAT(cont, ElementsAre(1, 2, 3));
}

TEST(FlatSet, MoveConstructor) {
  int input_range[] = {1, 2, 3, 4};

  flat_set<MoveOnlyInt> original(std::begin(input_range),
                                 std::end(input_range));
  flat_set<MoveOnlyInt> moved(std::move(original));

  EXPECT_EQ(1U, moved.count(MoveOnlyInt(1)));
  EXPECT_EQ(1U, moved.count(MoveOnlyInt(2)));
  EXPECT_EQ(1U, moved.count(MoveOnlyInt(3)));
  EXPECT_EQ(1U, moved.count(MoveOnlyInt(4)));
}

TEST(FlatSet, InitializerListConstructor) {
  flat_set<int> cont({1, 2, 3, 4, 5, 6, 10, 8});
  EXPECT_THAT(cont, ElementsAre(1, 2, 3, 4, 5, 6, 8, 10));
}

TEST(FlatSet, InsertFindSize) {
  base::flat_set<int> s;
  s.insert(1);
  s.insert(1);
  s.insert(2);

  EXPECT_EQ(2u, s.size());
  EXPECT_EQ(1, *s.find(1));
  EXPECT_EQ(2, *s.find(2));
  EXPECT_EQ(s.end(), s.find(7));
}

TEST(FlatSet, CopySwap) {
  base::flat_set<int> original;
  original.insert(1);
  original.insert(2);
  EXPECT_THAT(original, ElementsAre(1, 2));

  base::flat_set<int> copy(original);
  EXPECT_THAT(copy, ElementsAre(1, 2));

  copy.erase(copy.begin());
  copy.insert(10);
  EXPECT_THAT(copy, ElementsAre(2, 10));

  original.swap(copy);
  EXPECT_THAT(original, ElementsAre(2, 10));
  EXPECT_THAT(copy, ElementsAre(1, 2));
}

TEST(FlatSet, UsingTransparentCompare) {
  using ExplicitInt = base::MoveOnlyInt;
  base::flat_set<ExplicitInt> s;
  const auto& s1 = s;
  int x = 0;

  // Check if we can use lookup functions without converting to key_type.
  // Correctness is checked in flat_tree tests.
  s.count(x);
  s1.count(x);
  s.find(x);
  s1.find(x);
  s.contains(x);
  s1.contains(x);
  s.equal_range(x);
  s1.equal_range(x);
  s.lower_bound(x);
  s1.lower_bound(x);
  s.upper_bound(x);
  s1.upper_bound(x);
  s.erase(x);

  // Check if we broke overload resolution.
  s.emplace(0);
  s.emplace(1);
  s.erase(s.begin());
  s.erase(s.cbegin());
}

TEST(FlatSet, UsingInitializerList) {
  base::flat_set<ImplicitInt> s;
  const auto& s1 = s;

  // Check if the calls can be resolved. Correctness is checked in flat_tree
  // tests.
  s.count({1});
  s1.count({2});
  s.find({3});
  s1.find({4});
  s.contains({5});
  s1.contains({6});
  s.equal_range({7});
  s1.equal_range({8});
  s.lower_bound({9});
  s1.lower_bound({10});
  s.upper_bound({11});
  s1.upper_bound({12});
  s.erase({13});
}

}  // namespace base