cpp-useful-iterators/test/recursive_iterator_accessors_test.cxx

#include "iterator/recursive_iterator.hpp"

#include <map>
#include <vector>

#include <gmock/gmock.h>

TEST(RecursiveIteratorTest, CanStdGetToAllLayersOfInternalIteration) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator(obj);
  EXPECT_TRUE((testing::StaticAssertTypeEq<
               decltype(std::get<0>(rit)),
               iterator::end_aware_iterator<decltype(obj)::iterator>>()));
  EXPECT_TRUE(
      (testing::StaticAssertTypeEq<decltype(std::get<1>(rit)),
                                   iterator::end_aware_iterator<std::vector<
                                       std::map<int, int>>::iterator>>()));
  EXPECT_TRUE((testing::StaticAssertTypeEq<
               decltype(std::get<2>(rit)),
               iterator::end_aware_iterator<std::map<int, int>::iterator>>()));
  EXPECT_TRUE((testing::StaticAssertTypeEq<
               decltype(*rit), std::tuple<int const &, int const &, int &>>()));
}

TEST(RecursiveIteratorTest, CanAccessInternalIteratorsWithGet) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator(obj);
  EXPECT_THAT(std::get<0>(rit), make_end_aware_iterator(obj));
  EXPECT_THAT(std::get<1>(rit), make_end_aware_iterator(obj[1]));
  EXPECT_THAT(std::get<2>(rit), make_end_aware_iterator(obj[1][0]));
}

// TODO: This ought to be implemented as a compiles-test
TEST(RecursiveIteratorTest, CanCastCompatibleIterators) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator(obj);
  iterator::recursive_iterator<decltype(obj)::const_iterator> cit(rit);
}

TEST(RecursiveIteratorTest, EmptyCtorIsEnd) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator(obj);
  EXPECT_THAT(rit, testing::Ne(decltype(rit)()));
  EXPECT_THAT(std::distance(rit, decltype(rit)()), 4);
  std::advance(rit, 4);
  EXPECT_THAT(rit, decltype(rit)());
}

TEST(BoundedRecursiveIteratorTest, CanStdGetToNLayersOfInternalIteration) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator<2>(obj);
  EXPECT_TRUE((testing::StaticAssertTypeEq<
               decltype(std::get<0>(rit)),
               iterator::end_aware_iterator<decltype(obj)::iterator>>()));
  EXPECT_TRUE(
      (testing::StaticAssertTypeEq<decltype(std::get<1>(rit)),
                                   iterator::end_aware_iterator<std::vector<
                                       std::map<int, int>>::iterator>>()));
  EXPECT_TRUE(
      (testing::StaticAssertTypeEq<
          decltype(*rit), std::tuple<int const &, std::map<int, int> &>>()));
}

TEST(BoundedRecursiveIteratorTest, CanAccessInternalIteratorsWithGet) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator<2>(obj);
  EXPECT_THAT(std::get<0>(rit), make_end_aware_iterator(obj));
  EXPECT_THAT(std::get<1>(rit), make_end_aware_iterator(obj[1]));
}

// TODO: This ought to be implemented as a compiles-test
TEST(BoundedRecursiveIteratorTest, CanCastCompatibleIterators) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator<2>(obj);
  iterator::recursive_iterator_n<decltype(obj)::const_iterator, 2> cit(rit);
}

TEST(BoundedRecursiveIteratorTest, EmptyCtorIsEnd) {
  std::map<int, std::vector<std::map<int, int>>> obj{
      {1, {{{1, 1}}, {{2, 2}}}}, // 2 1-element maps
      {2, {{{3, 3}, {4, 4}}}}    // 1 2-element map
  };
  auto rit = make_recursive_iterator<2>(obj);
  EXPECT_THAT(rit, testing::Ne(decltype(rit)()));
  EXPECT_THAT(std::distance(rit, decltype(rit)()), 3);
  std::advance(rit, 3);
  EXPECT_THAT(rit, decltype(rit)());
}

// TEST(RecursiveIteratorTest, CanConstructInPlaceFromIterators) {
//  std::map<int, std::vector<std::map<int, int>>> const obj{
//      {1, {{{1, 1}}, {{2, 2}}}}, {2, {{{3, 3}, {4, 4}}}}};
//  auto const it = make_end_aware_iterator(obj.begin(), obj.end());
//  auto const it_1 = ++make_end_aware_iterator(it->second);
//  auto const it_2 = make_end_aware_iterator(*it_1);
//  // Note that this carries the weakness of non bounds-checking that our
//  // iterators are all sitting on the same hierarchy...
//  EXPECT_NO_THROW(make_recursive_iterator(it, it_1, it_2));
//}
//
// TEST(RecursiveIteratorTest, InternalIteratorsFromStdGetMatchCtorArgs) {
//  std::map<int, std::vector<std::map<int, int>>> const obj{
//      {1, {{{1, 1}}, {{2, 2}}}}, {2, {{{3, 3}, {4, 4}}}}};
//  auto const it = make_end_aware_iterator(obj.begin(), obj.end());
//  auto const it_1 = ++make_end_aware_iterator(it->second);
//  auto const it_2 = make_end_aware_iterator(*it_1);
//  iterator::recursive_iterator<decltype(obj.cbegin())> rit{iterator::in_place,
//                                                           it, it_1, it_2};
//  EXPECT_THAT(std::get<0>(rit), it);
//  EXPECT_THAT(std::get<1>(rit), it_1);
//  EXPECT_THAT(std::get<2>(rit), it_2);
//}