123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474475476477478479480481482483484485486487488489490491492493494495496497498499500501502503504505506507508509510511512513514515516517518519520521522523524525526527528529530531532533534535536537538539540541542543544 |
- /*
- * Copyright 2017-present Facebook, Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- #include <algorithm>
- #include <cassert>
- #include <cstddef>
- #include <deque>
- #include <functional>
- #include <map>
- #include <set>
- #include <tuple>
- #include <type_traits>
- #include <utility>
- #include <vector>
- #include <folly/container/Iterator.h>
- #include <folly/portability/GTest.h>
- namespace {
- /**
- * Container type used for unit tests.
- */
- template <typename T>
- using Container = std::deque<T>;
- // Constructor and assignment operator call counters for struct Object.
- std::size_t gDefaultCtrCnt;
- std::size_t gCopyCtrCnt;
- std::size_t gMoveCtrCnt;
- std::size_t gExplicitCtrCnt;
- std::size_t gMultiargCtrCnt;
- std::size_t gCopyOpCnt;
- std::size_t gMoveOpCnt;
- std::size_t gConvertOpCnt;
- /**
- * Class that increases various counters to keep track of how objects have
- * been constructed or assigned to, to verify iterator behavior.
- */
- struct Object {
- Object() {
- ++gDefaultCtrCnt;
- }
- Object(const Object&) {
- ++gCopyCtrCnt;
- }
- Object(Object&&) noexcept {
- ++gMoveCtrCnt;
- }
- explicit Object(int) {
- ++gExplicitCtrCnt;
- }
- explicit Object(int, int) {
- ++gMultiargCtrCnt;
- }
- Object& operator=(const Object&) {
- ++gCopyOpCnt;
- return *this;
- }
- Object& operator=(Object&&) noexcept {
- ++gMoveOpCnt;
- return *this;
- }
- Object& operator=(int) noexcept {
- ++gConvertOpCnt;
- return *this;
- }
- };
- /**
- * Reset all call counters to 0.
- */
- void init_counters() {
- gDefaultCtrCnt = gCopyCtrCnt = gMoveCtrCnt = gExplicitCtrCnt =
- gMultiargCtrCnt = gCopyOpCnt = gMoveOpCnt = gConvertOpCnt = 0;
- }
- /**
- * Test for iterator copy and move.
- */
- template <typename Iterator>
- void copy_and_move_test(Container<int>& q, Iterator it) {
- assert(q.empty());
- const auto it2(it); // copy construct
- it = it2; // copy assign from const
- it = it; // self assign
- auto it3(std::move(it)); // move construct
- it = std::move(it3); // move assign
- // Make sure iterator still works.
- it = 4711; // emplace
- EXPECT_EQ(q, Container<int>{4711});
- }
- /**
- * Test for emplacement with perfect forwarding.
- */
- template <typename Iterator>
- void emplace_test(Container<Object>& q, Iterator it) {
- using folly::make_emplace_args;
- assert(q.empty());
- init_counters();
- it = Object{}; // default construct + move construct
- Object obj; // default construct
- it = obj; // copy construct
- it = std::move(obj); // move construct
- const Object obj2; // default construct
- it = obj2; // copy construct from const
- it = std::move(obj2); // copy construct (const defeats move)
- it = 0; // explicit construct
- it = make_emplace_args(0, 0); // explicit multiarg construct
- it = std::make_pair(0, 0); // implicit multiarg construct
- it = std::make_tuple(0, 0); // implicit multiarg construct
- auto args = make_emplace_args(Object{}); // default construct + move construct
- it = args; // copy construct
- it = const_cast<const decltype(args)&>(args); // copy construct from const
- it = std::move(args); // move construct
- auto args2 = std::make_tuple(Object{}); // default construct + move construct
- it = args2; // (implicit multiarg) copy construct
- it = std::move(args2); // (implicit multiarg) move construct
- auto args3 = std::make_pair(0, 0);
- it = args3; // implicit multiarg construct
- it = std::move(args3); // implicit multiarg construct
- ASSERT_EQ(q.size(), 16);
- EXPECT_EQ(gDefaultCtrCnt, 5);
- EXPECT_EQ(gCopyCtrCnt, 6);
- EXPECT_EQ(gMoveCtrCnt, 6);
- EXPECT_EQ(gExplicitCtrCnt, 1);
- EXPECT_EQ(gMultiargCtrCnt, 5);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- }
- } // namespace
- using namespace folly;
- /**
- * Basic tests for folly::emplace_iterator.
- */
- TEST(EmplaceIterator, EmplacerTest) {
- {
- Container<int> q;
- copy_and_move_test(q, emplacer(q, q.begin()));
- }
- {
- Container<Object> q;
- emplace_test(q, emplacer(q, q.begin()));
- }
- {
- Container<int> q;
- auto it = emplacer(q, q.begin());
- it = 0;
- it = 1;
- it = 2;
- it = emplacer(q, q.begin());
- it = 3;
- it = 4;
- EXPECT_EQ(q, Container<int>({3, 4, 0, 1, 2}));
- }
- }
- /**
- * Basic tests for folly::front_emplace_iterator.
- */
- TEST(EmplaceIterator, FrontEmplacerTest) {
- {
- Container<int> q;
- copy_and_move_test(q, front_emplacer(q));
- }
- {
- Container<Object> q;
- emplace_test(q, front_emplacer(q));
- }
- {
- Container<int> q;
- auto it = front_emplacer(q);
- it = 0;
- it = 1;
- it = 2;
- it = front_emplacer(q);
- it = 3;
- it = 4;
- EXPECT_EQ(q, Container<int>({4, 3, 2, 1, 0}));
- }
- }
- /**
- * Basic tests for folly::back_emplace_iterator.
- */
- TEST(EmplaceIterator, BackEmplacerTest) {
- {
- Container<int> q;
- copy_and_move_test(q, back_emplacer(q));
- }
- {
- Container<Object> q;
- emplace_test(q, back_emplacer(q));
- }
- {
- Container<int> q;
- auto it = back_emplacer(q);
- it = 0;
- it = 1;
- it = 2;
- it = back_emplacer(q);
- it = 3;
- it = 4;
- EXPECT_EQ(q, Container<int>({0, 1, 2, 3, 4}));
- }
- }
- /**
- * Basic tests for folly::hint_emplace_iterator.
- */
- TEST(EmplaceIterator, HintEmplacerTest) {
- {
- init_counters();
- std::map<int, Object> m;
- auto it = hint_emplacer(m, m.end());
- it = make_emplace_args(
- std::piecewise_construct,
- std::forward_as_tuple(0),
- std::forward_as_tuple(0));
- it = make_emplace_args(
- std::piecewise_construct,
- std::forward_as_tuple(1),
- std::forward_as_tuple(0, 0));
- it = make_emplace_args(
- std::piecewise_construct,
- std::forward_as_tuple(2),
- std::forward_as_tuple(Object{}));
- ASSERT_EQ(m.size(), 3);
- EXPECT_EQ(gDefaultCtrCnt, 1);
- EXPECT_EQ(gCopyCtrCnt, 0);
- EXPECT_EQ(gMoveCtrCnt, 1);
- EXPECT_EQ(gExplicitCtrCnt, 1);
- EXPECT_EQ(gMultiargCtrCnt, 1);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- }
- {
- struct O {
- explicit O(int i_) : i(i_) {}
- bool operator<(const O& other) const {
- return i < other.i;
- }
- bool operator==(const O& other) const {
- return i == other.i;
- }
- int i;
- };
- std::vector<int> v1 = {0, 1, 2, 3, 4};
- std::vector<int> v2 = {0, 2, 4};
- std::set<O> diff;
- std::set_difference(
- v1.begin(),
- v1.end(),
- v2.begin(),
- v2.end(),
- hint_emplacer(diff, diff.end()));
- ASSERT_EQ(diff, std::set<O>({O(1), O(3)}));
- }
- }
- /**
- * Test std::copy() with explicit conversion. This would not compile with a
- * std::back_insert_iterator, because the constructor of Object that takes a
- * single int is explicit.
- */
- TEST(EmplaceIterator, Copy) {
- init_counters();
- Container<int> in({0, 1, 2});
- Container<Object> out;
- std::copy(in.begin(), in.end(), back_emplacer(out));
- EXPECT_EQ(3, out.size());
- EXPECT_EQ(gDefaultCtrCnt, 0);
- EXPECT_EQ(gCopyCtrCnt, 0);
- EXPECT_EQ(gMoveCtrCnt, 0);
- EXPECT_EQ(gExplicitCtrCnt, 3);
- EXPECT_EQ(gMultiargCtrCnt, 0);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- }
- /**
- * Test std::transform() with multi-argument constructors. This would require
- * a temporary Object with std::back_insert_iterator.
- */
- TEST(EmplaceIterator, Transform) {
- init_counters();
- Container<int> in({0, 1, 2});
- Container<Object> out;
- std::transform(in.begin(), in.end(), back_emplacer(out), [](int i) {
- return make_emplace_args(i, i);
- });
- EXPECT_EQ(3, out.size());
- EXPECT_EQ(gDefaultCtrCnt, 0);
- EXPECT_EQ(gCopyCtrCnt, 0);
- EXPECT_EQ(gMoveCtrCnt, 0);
- EXPECT_EQ(gExplicitCtrCnt, 0);
- EXPECT_EQ(gMultiargCtrCnt, 3);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- }
- /**
- * Test multi-argument store and forward.
- */
- TEST(EmplaceIterator, EmplaceArgs) {
- Object o1;
- const Object o2;
- Object& o3 = o1;
- const Object& o4 = o3;
- Object o5;
- {
- // Test copy construction.
- auto args = make_emplace_args(0, o1, o2, o3, o4, Object{}, std::cref(o2));
- init_counters();
- auto args2 = args;
- EXPECT_EQ(gDefaultCtrCnt, 0);
- EXPECT_EQ(gCopyCtrCnt, 5);
- EXPECT_EQ(gMoveCtrCnt, 0);
- EXPECT_EQ(gExplicitCtrCnt, 0);
- EXPECT_EQ(gMultiargCtrCnt, 0);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- // Test copy assignment.
- init_counters();
- args = args2;
- EXPECT_EQ(gDefaultCtrCnt, 0);
- EXPECT_EQ(gCopyCtrCnt, 0);
- EXPECT_EQ(gMoveCtrCnt, 0);
- EXPECT_EQ(gExplicitCtrCnt, 0);
- EXPECT_EQ(gMultiargCtrCnt, 0);
- EXPECT_EQ(gCopyOpCnt, 5);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- }
- {
- // Test RVO.
- init_counters();
- auto args = make_emplace_args(
- 0, o1, o2, o3, o4, Object{}, std::cref(o2), rref(std::move(o5)));
- EXPECT_EQ(gDefaultCtrCnt, 1);
- EXPECT_EQ(gCopyCtrCnt, 4);
- EXPECT_EQ(gMoveCtrCnt, 1);
- EXPECT_EQ(gExplicitCtrCnt, 0);
- EXPECT_EQ(gMultiargCtrCnt, 0);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- // Test move construction.
- init_counters();
- auto args2 = std::move(args);
- EXPECT_EQ(gDefaultCtrCnt, 0);
- EXPECT_EQ(gCopyCtrCnt, 0);
- EXPECT_EQ(gMoveCtrCnt, 5);
- EXPECT_EQ(gExplicitCtrCnt, 0);
- EXPECT_EQ(gMultiargCtrCnt, 0);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 0);
- EXPECT_EQ(gConvertOpCnt, 0);
- // Test move assignment.
- init_counters();
- args = std::move(args2);
- EXPECT_EQ(gDefaultCtrCnt, 0);
- EXPECT_EQ(gCopyCtrCnt, 0);
- EXPECT_EQ(gMoveCtrCnt, 0);
- EXPECT_EQ(gExplicitCtrCnt, 0);
- EXPECT_EQ(gMultiargCtrCnt, 0);
- EXPECT_EQ(gCopyOpCnt, 0);
- EXPECT_EQ(gMoveOpCnt, 5);
- EXPECT_EQ(gConvertOpCnt, 0);
- // Make sure arguments are stored correctly. lvalues by reference, rvalues
- // by (moved) copy. Rvalues cannot be stored by reference because they may
- // refer to an expired temporary by the time they are accessed.
- static_assert(
- std::is_same<
- int,
- std::tuple_element_t<0, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- Object,
- std::tuple_element_t<1, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- Object,
- std::tuple_element_t<2, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- Object,
- std::tuple_element_t<3, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- Object,
- std::tuple_element_t<4, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- Object,
- std::tuple_element_t<5, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- std::reference_wrapper<const Object>,
- std::tuple_element_t<6, decltype(args)::storage_type>>::value,
- "");
- static_assert(
- std::is_same<
- rvalue_reference_wrapper<Object>,
- std::tuple_element_t<7, decltype(args)::storage_type>>::value,
- "");
- // Check whether args.get() restores the original argument type for
- // rvalue references to emplace_args.
- static_assert(
- std::is_same<int&&, decltype(get_emplace_arg<0>(std::move(args)))>::
- value,
- "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<1>(std::move(args)))>::
- value,
- "");
- static_assert(
- std::is_same<
- const Object&,
- decltype(get_emplace_arg<2>(std::move(args)))>::value,
- "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<3>(std::move(args)))>::
- value,
- "");
- static_assert(
- std::is_same<
- const Object&,
- decltype(get_emplace_arg<4>(std::move(args)))>::value,
- "");
- static_assert(
- std::is_same<Object&&, decltype(get_emplace_arg<5>(std::move(args)))>::
- value,
- "");
- static_assert(
- std::is_same<
- const Object&,
- decltype(get_emplace_arg<6>(std::move(args)))>::value,
- "");
- static_assert(
- std::is_same<Object&&, decltype(get_emplace_arg<7>(std::move(args)))>::
- value,
- "");
- // lvalue references to emplace_args should behave mostly like std::tuples.
- // Note that get_emplace_arg<7>(args) does not compile, because
- // folly::rvalue_reference_wrappers can only be unwrapped through an rvalue
- // reference.
- static_assert(
- std::is_same<int&, decltype(get_emplace_arg<0>(args))>::value, "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<1>(args))>::value, "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<2>(args))>::value, "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<3>(args))>::value, "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<4>(args))>::value, "");
- static_assert(
- std::is_same<Object&, decltype(get_emplace_arg<5>(args))>::value, "");
- static_assert(
- std::is_same<const Object&, decltype(get_emplace_arg<6>(args))>::value,
- "");
- }
- }
- /**
- * Test implicit unpacking.
- */
- TEST(EmplaceIterator, ImplicitUnpack) {
- static std::size_t multiCtrCnt;
- static std::size_t pairCtrCnt;
- static std::size_t tupleCtrCnt;
- struct Object2 {
- Object2(int, int) {
- ++multiCtrCnt;
- }
- explicit Object2(const std::pair<int, int>&) {
- ++pairCtrCnt;
- }
- explicit Object2(const std::tuple<int, int>&) {
- ++tupleCtrCnt;
- }
- };
- auto test = [](auto&& it, bool expectUnpack) {
- multiCtrCnt = pairCtrCnt = tupleCtrCnt = 0;
- it = std::make_pair(0, 0);
- it = std::make_tuple(0, 0);
- if (expectUnpack) {
- EXPECT_EQ(multiCtrCnt, 2);
- EXPECT_EQ(pairCtrCnt, 0);
- EXPECT_EQ(tupleCtrCnt, 0);
- } else {
- EXPECT_EQ(multiCtrCnt, 0);
- EXPECT_EQ(pairCtrCnt, 1);
- EXPECT_EQ(tupleCtrCnt, 1);
- }
- };
- Container<Object2> q;
- test(emplacer(q, q.begin()), true);
- test(emplacer<false>(q, q.begin()), false);
- test(front_emplacer(q), true);
- test(front_emplacer<false>(q), false);
- test(back_emplacer(q), true);
- test(back_emplacer<false>(q), false);
- }
|