2 * Copyright 2015 Facebook, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
17 #include <folly/Optional.h>
25 #include <glog/logging.h>
26 #include <gtest/gtest.h>
27 #include <boost/optional.hpp>
29 using std::unique_ptr;
30 using std::shared_ptr;
35 std::ostream& operator<<(std::ostream& os, const Optional<V>& v) {
37 os << "Optional(" << v.value() << ')';
45 NoDefault(int, int) {}
49 static_assert(sizeof(Optional<char>) == 2, "");
50 static_assert(sizeof(Optional<int>) == 8, "");
51 static_assert(sizeof(Optional<NoDefault>) == 4, "");
52 static_assert(sizeof(Optional<char>) == sizeof(boost::optional<char>), "");
53 static_assert(sizeof(Optional<short>) == sizeof(boost::optional<short>), "");
54 static_assert(sizeof(Optional<int>) == sizeof(boost::optional<int>), "");
55 static_assert(sizeof(Optional<double>) == sizeof(boost::optional<double>), "");
57 TEST(Optional, NoDefault) {
58 Optional<NoDefault> x;
66 TEST(Optional, String) {
67 Optional<std::string> maybeString;
68 EXPECT_FALSE(maybeString);
69 maybeString = "hello";
70 EXPECT_TRUE(bool(maybeString));
73 TEST(Optional, Const) {
74 { // default construct
75 Optional<const int> opt;
76 EXPECT_FALSE(bool(opt));
82 EXPECT_FALSE(bool(opt));
86 Optional<const int> opt(x);
91 Optional<const int> opt(std::move(x));
94 // no assignment allowed
97 TEST(Optional, Simple) {
99 EXPECT_FALSE(bool(opt));
100 EXPECT_EQ(42, opt.value_or(42));
102 EXPECT_TRUE(bool(opt));
104 EXPECT_EQ(4, opt.value_or(42));
108 EXPECT_FALSE(bool(opt));
113 /* implicit */ MoveTester(const char* s) : s_(s) {}
114 MoveTester(const MoveTester&) = default;
115 MoveTester(MoveTester&& other) noexcept {
116 s_ = std::move(other.s_);
119 MoveTester& operator=(const MoveTester&) = default;
120 MoveTester& operator=(MoveTester&& other) noexcept {
121 s_ = std::move(other.s_);
126 friend bool operator==(const MoveTester& o1, const MoveTester& o2);
130 bool operator==(const MoveTester& o1, const MoveTester& o2) {
131 return o1.s_ == o2.s_;
134 TEST(Optional, value_or_rvalue_arg) {
135 Optional<MoveTester> opt;
136 MoveTester dflt = "hello";
137 EXPECT_EQ("hello", opt.value_or(dflt));
138 EXPECT_EQ("hello", dflt);
139 EXPECT_EQ("hello", opt.value_or(std::move(dflt)));
141 EXPECT_EQ("world", opt.value_or("world"));
144 // Make sure that the const overload works on const objects
145 const auto& optc = opt;
146 EXPECT_EQ("hello", optc.value_or(dflt));
147 EXPECT_EQ("hello", dflt);
148 EXPECT_EQ("hello", optc.value_or(std::move(dflt)));
150 EXPECT_EQ("world", optc.value_or("world"));
154 EXPECT_EQ("meow", opt.value_or(dflt));
155 EXPECT_EQ("hello", dflt);
156 EXPECT_EQ("meow", opt.value_or(std::move(dflt)));
157 EXPECT_EQ("hello", dflt); // only moved if used
160 TEST(Optional, value_or_noncopyable) {
161 Optional<std::unique_ptr<int>> opt;
162 std::unique_ptr<int> dflt(new int(42));
163 EXPECT_EQ(42, *std::move(opt).value_or(std::move(dflt)));
166 struct ExpectingDeleter {
167 explicit ExpectingDeleter(int expected) : expected(expected) { }
169 void operator()(const int* ptr) {
170 EXPECT_EQ(*ptr, expected);
175 TEST(Optional, value_life_extention) {
176 // Extends the life of the value.
177 const auto& ptr = Optional<std::unique_ptr<int, ExpectingDeleter>>(
178 {new int(42), ExpectingDeleter{1337}}).value();
182 TEST(Optional, value_move) {
183 auto ptr = Optional<std::unique_ptr<int, ExpectingDeleter>>(
184 {new int(42), ExpectingDeleter{1337}}).value();
188 TEST(Optional, dereference_life_extention) {
189 // Extends the life of the value.
190 const auto& ptr = *Optional<std::unique_ptr<int, ExpectingDeleter>>(
191 {new int(42), ExpectingDeleter{1337}});
195 TEST(Optional, dereference_move) {
196 auto ptr = *Optional<std::unique_ptr<int, ExpectingDeleter>>(
197 {new int(42), ExpectingDeleter{1337}});
201 TEST(Optional, EmptyConstruct) {
203 EXPECT_FALSE(bool(opt));
204 Optional<int> test1(opt);
205 EXPECT_FALSE(bool(test1));
206 Optional<int> test2(std::move(opt));
207 EXPECT_FALSE(bool(test2));
210 TEST(Optional, Unique) {
211 Optional<unique_ptr<int>> opt;
214 EXPECT_FALSE(bool(opt));
216 opt.emplace(new int(5));
217 EXPECT_TRUE(bool(opt));
222 opt = unique_ptr<int>(new int(6));
225 opt = unique_ptr<int>(new int(7));
228 // move it out by move construct
229 Optional<unique_ptr<int>> moved(std::move(opt));
230 EXPECT_TRUE(bool(moved));
231 EXPECT_FALSE(bool(opt));
232 EXPECT_EQ(7, **moved);
234 EXPECT_TRUE(bool(moved));
235 opt = std::move(moved); // move it back by move assign
236 EXPECT_FALSE(bool(moved));
237 EXPECT_TRUE(bool(opt));
241 TEST(Optional, Shared) {
243 Optional<shared_ptr<int>> opt;
244 EXPECT_FALSE(bool(opt));
246 opt.emplace(new int(5));
247 EXPECT_TRUE(bool(opt));
249 EXPECT_EQ(ptr.get(), opt->get());
250 EXPECT_EQ(2, ptr.use_count());
252 EXPECT_EQ(1, ptr.use_count());
255 EXPECT_EQ(2, ptr.use_count());
256 EXPECT_EQ(ptr.get(), opt->get());
258 EXPECT_EQ(1, ptr.use_count());
260 opt = std::move(ptr);
261 EXPECT_EQ(1, opt->use_count());
262 EXPECT_EQ(nullptr, ptr.get());
264 Optional<shared_ptr<int>> copied(opt);
265 EXPECT_EQ(2, opt->use_count());
266 Optional<shared_ptr<int>> moved(std::move(opt));
267 EXPECT_EQ(2, moved->use_count());
268 moved.emplace(new int(6));
269 EXPECT_EQ(1, moved->use_count());
271 EXPECT_EQ(2, moved->use_count());
275 TEST(Optional, Order) {
276 std::vector<Optional<int>> vect{
283 std::vector<Optional<int>> expected {
290 std::sort(vect.begin(), vect.end());
291 EXPECT_EQ(vect, expected);
294 TEST(Optional, Swap) {
295 Optional<std::string> a;
296 Optional<std::string> b;
299 EXPECT_FALSE(a.hasValue());
300 EXPECT_FALSE(b.hasValue());
303 EXPECT_TRUE(a.hasValue());
304 EXPECT_FALSE(b.hasValue());
305 EXPECT_EQ("hello", a.value());
308 EXPECT_FALSE(a.hasValue());
309 EXPECT_TRUE(b.hasValue());
310 EXPECT_EQ("hello", b.value());
313 EXPECT_TRUE(a.hasValue());
314 EXPECT_EQ("bye", a.value());
319 TEST(Optional, Comparisons) {
324 EXPECT_TRUE(o_ <= (o_));
325 EXPECT_TRUE(o_ == (o_));
326 EXPECT_TRUE(o_ >= (o_));
328 EXPECT_TRUE(o1 < o2);
329 EXPECT_TRUE(o1 <= o2);
330 EXPECT_TRUE(o1 <= (o1));
331 EXPECT_TRUE(o1 == (o1));
332 EXPECT_TRUE(o1 != o2);
333 EXPECT_TRUE(o1 >= (o1));
334 EXPECT_TRUE(o2 >= o1);
335 EXPECT_TRUE(o2 > o1);
337 EXPECT_FALSE(o2 < o1);
338 EXPECT_FALSE(o2 <= o1);
339 EXPECT_FALSE(o2 <= o1);
340 EXPECT_FALSE(o2 == o1);
341 EXPECT_FALSE(o1 != (o1));
342 EXPECT_FALSE(o1 >= o2);
343 EXPECT_FALSE(o1 >= o2);
344 EXPECT_FALSE(o1 > o2);
346 /* folly::Optional explicitly doesn't support comparisons with contained value
348 EXPECT_TRUE(1 <= o2);
349 EXPECT_TRUE(1 <= o1);
350 EXPECT_TRUE(1 == o1);
351 EXPECT_TRUE(2 != o1);
352 EXPECT_TRUE(1 >= o1);
353 EXPECT_TRUE(2 >= o1);
356 EXPECT_FALSE(o2 < 1);
357 EXPECT_FALSE(o2 <= 1);
358 EXPECT_FALSE(o2 <= 1);
359 EXPECT_FALSE(o2 == 1);
360 EXPECT_FALSE(o2 != 2);
361 EXPECT_FALSE(o1 >= 2);
362 EXPECT_FALSE(o1 >= 2);
363 EXPECT_FALSE(o1 > 2);
366 // boost::optional does support comparison with contained value, which can
367 // lead to confusion when a bool is contained
368 boost::optional<int> boi(3);
369 EXPECT_TRUE(boi < 5);
370 EXPECT_TRUE(boi <= 4);
371 EXPECT_TRUE(boi == 3);
372 EXPECT_TRUE(boi != 2);
373 EXPECT_TRUE(boi >= 1);
374 EXPECT_TRUE(boi > 0);
375 EXPECT_TRUE(1 < boi);
376 EXPECT_TRUE(2 <= boi);
377 EXPECT_TRUE(3 == boi);
378 EXPECT_TRUE(4 != boi);
379 EXPECT_TRUE(5 >= boi);
380 EXPECT_TRUE(6 > boi);
382 boost::optional<bool> bob(false);
383 EXPECT_TRUE((bool)bob);
384 EXPECT_TRUE(bob == false); // well that was confusing
385 EXPECT_FALSE(bob != false);
388 TEST(Optional, Conversions) {
389 Optional<bool> mbool;
390 Optional<short> mshort;
391 Optional<char*> mstr;
394 //These don't compile
403 // intended explicit operator bool, for if (opt).
407 // Truthy tests work and are not ambiguous
408 if (mbool && mshort && mstr && mint) { // only checks not-empty
409 if (*mbool && *mshort && *mstr && *mint) { // only checks value
415 EXPECT_TRUE(bool(mbool));
416 EXPECT_FALSE(*mbool);
419 EXPECT_TRUE(bool(mbool));
423 EXPECT_FALSE(bool(mbool));
425 // No conversion allowed; does not compile
426 // EXPECT_TRUE(mbool == false);
429 TEST(Optional, Pointee) {
431 EXPECT_FALSE(get_pointer(x));
433 EXPECT_TRUE(get_pointer(x));
435 EXPECT_TRUE(*x == 2);
437 EXPECT_FALSE(get_pointer(x));
440 TEST(Optional, MakeOptional) {
441 // const L-value version
442 const std::string s("abc");
443 auto optStr = make_optional(s);
444 ASSERT_TRUE(optStr.hasValue());
445 EXPECT_EQ(*optStr, "abc");
448 EXPECT_EQ(*optStr, "cde");
451 std::string s2("abc");
452 auto optStr2 = make_optional(s2);
453 ASSERT_TRUE(optStr2.hasValue());
454 EXPECT_EQ(*optStr2, "abc");
456 // it's vital to check that s2 wasn't clobbered
457 EXPECT_EQ(s2, "abc");
459 // L-value reference version
461 auto optStr3 = make_optional(s3);
462 ASSERT_TRUE(optStr3.hasValue());
463 EXPECT_EQ(*optStr3, "abc");
465 EXPECT_EQ(s3, "abc");
467 // R-value ref version
468 unique_ptr<int> pInt(new int(3));
469 auto optIntPtr = make_optional(std::move(pInt));
470 EXPECT_TRUE(pInt.get() == nullptr);
471 ASSERT_TRUE(optIntPtr.hasValue());
472 EXPECT_EQ(**optIntPtr, 3);
476 # pragma clang diagnostic push
477 # if __clang_major__ > 3 || __clang_minor__ >= 6
478 # pragma clang diagnostic ignored "-Wself-move"
482 TEST(Optional, SelfAssignment) {
483 Optional<int> a = 42;
485 ASSERT_TRUE(a.hasValue() && a.value() == 42);
487 Optional<int> b = 23333333;
489 ASSERT_TRUE(b.hasValue() && b.value() == 23333333);
493 #pragma clang diagnostic pop
496 class ContainsOptional {
498 ContainsOptional() { }
499 explicit ContainsOptional(int x) : opt_(x) { }
500 bool hasValue() const { return opt_.hasValue(); }
501 int value() const { return opt_.value(); }
503 ContainsOptional(const ContainsOptional &other) = default;
504 ContainsOptional& operator=(const ContainsOptional &other) = default;
505 ContainsOptional(ContainsOptional &&other) = default;
506 ContainsOptional& operator=(ContainsOptional &&other) = default;
513 * Test that a class containing an Optional can be copy and move assigned.
514 * This was broken under gcc 4.7 until assignment operators were explicitly
517 TEST(Optional, AssignmentContained) {
519 ContainsOptional source(5), target;
521 EXPECT_TRUE(target.hasValue());
522 EXPECT_EQ(5, target.value());
526 ContainsOptional source(5), target;
527 target = std::move(source);
528 EXPECT_TRUE(target.hasValue());
529 EXPECT_EQ(5, target.value());
530 EXPECT_FALSE(source.hasValue());
534 ContainsOptional opt_uninit, target(10);
536 EXPECT_FALSE(target.hasValue());
540 TEST(Optional, Exceptions) {
542 EXPECT_THROW(empty.value(), OptionalEmptyException);