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&&) = default;
122 friend bool operator==(const MoveTester& o1, const MoveTester& o2);
126 bool operator==(const MoveTester& o1, const MoveTester& o2) {
127 return o1.s_ == o2.s_;
130 TEST(Optional, value_or_rvalue_arg) {
131 Optional<MoveTester> opt;
132 MoveTester dflt = "hello";
133 EXPECT_EQ("hello", opt.value_or(dflt));
134 EXPECT_EQ("hello", dflt);
135 EXPECT_EQ("hello", opt.value_or(std::move(dflt)));
137 EXPECT_EQ("world", opt.value_or("world"));
140 // Make sure that the const overload works on const objects
141 const auto& optc = opt;
142 EXPECT_EQ("hello", optc.value_or(dflt));
143 EXPECT_EQ("hello", dflt);
144 EXPECT_EQ("hello", optc.value_or(std::move(dflt)));
146 EXPECT_EQ("world", optc.value_or("world"));
150 EXPECT_EQ("meow", opt.value_or(dflt));
151 EXPECT_EQ("hello", dflt);
152 EXPECT_EQ("meow", opt.value_or(std::move(dflt)));
153 EXPECT_EQ("hello", dflt); // only moved if used
156 TEST(Optional, value_or_noncopyable) {
157 Optional<std::unique_ptr<int>> opt;
158 std::unique_ptr<int> dflt(new int(42));
159 EXPECT_EQ(42, *std::move(opt).value_or(std::move(dflt)));
162 struct ExpectingDeleter {
163 explicit ExpectingDeleter(int expected) : expected(expected) { }
165 void operator()(const int* ptr) {
166 EXPECT_EQ(*ptr, expected);
171 TEST(Optional, value_life_extention) {
172 // Extends the life of the value.
173 const auto& ptr = Optional<std::unique_ptr<int, ExpectingDeleter>>(
174 {new int(42), ExpectingDeleter{1337}}).value();
178 TEST(Optional, value_move) {
179 auto ptr = Optional<std::unique_ptr<int, ExpectingDeleter>>(
180 {new int(42), ExpectingDeleter{1337}}).value();
184 TEST(Optional, dereference_life_extention) {
185 // Extends the life of the value.
186 const auto& ptr = *Optional<std::unique_ptr<int, ExpectingDeleter>>(
187 {new int(42), ExpectingDeleter{1337}});
191 TEST(Optional, dereference_move) {
192 auto ptr = *Optional<std::unique_ptr<int, ExpectingDeleter>>(
193 {new int(42), ExpectingDeleter{1337}});
197 TEST(Optional, EmptyConstruct) {
199 EXPECT_FALSE(bool(opt));
200 Optional<int> test1(opt);
201 EXPECT_FALSE(bool(test1));
202 Optional<int> test2(std::move(opt));
203 EXPECT_FALSE(bool(test2));
206 TEST(Optional, Unique) {
207 Optional<unique_ptr<int>> opt;
210 EXPECT_FALSE(bool(opt));
212 opt.emplace(new int(5));
213 EXPECT_TRUE(bool(opt));
218 opt = unique_ptr<int>(new int(6));
221 opt = unique_ptr<int>(new int(7));
224 // move it out by move construct
225 Optional<unique_ptr<int>> moved(std::move(opt));
226 EXPECT_TRUE(bool(moved));
227 EXPECT_FALSE(bool(opt));
228 EXPECT_EQ(7, **moved);
230 EXPECT_TRUE(bool(moved));
231 opt = std::move(moved); // move it back by move assign
232 EXPECT_FALSE(bool(moved));
233 EXPECT_TRUE(bool(opt));
237 TEST(Optional, Shared) {
239 Optional<shared_ptr<int>> opt;
240 EXPECT_FALSE(bool(opt));
242 opt.emplace(new int(5));
243 EXPECT_TRUE(bool(opt));
245 EXPECT_EQ(ptr.get(), opt->get());
246 EXPECT_EQ(2, ptr.use_count());
248 EXPECT_EQ(1, ptr.use_count());
251 EXPECT_EQ(2, ptr.use_count());
252 EXPECT_EQ(ptr.get(), opt->get());
254 EXPECT_EQ(1, ptr.use_count());
256 opt = std::move(ptr);
257 EXPECT_EQ(1, opt->use_count());
258 EXPECT_EQ(nullptr, ptr.get());
260 Optional<shared_ptr<int>> copied(opt);
261 EXPECT_EQ(2, opt->use_count());
262 Optional<shared_ptr<int>> moved(std::move(opt));
263 EXPECT_EQ(2, moved->use_count());
264 moved.emplace(new int(6));
265 EXPECT_EQ(1, moved->use_count());
267 EXPECT_EQ(2, moved->use_count());
271 TEST(Optional, Order) {
272 std::vector<Optional<int>> vect{
279 std::vector<Optional<int>> expected {
286 std::sort(vect.begin(), vect.end());
287 EXPECT_EQ(vect, expected);
290 TEST(Optional, Swap) {
291 Optional<std::string> a;
292 Optional<std::string> b;
295 EXPECT_FALSE(a.hasValue());
296 EXPECT_FALSE(b.hasValue());
299 EXPECT_TRUE(a.hasValue());
300 EXPECT_FALSE(b.hasValue());
301 EXPECT_EQ("hello", a.value());
304 EXPECT_FALSE(a.hasValue());
305 EXPECT_TRUE(b.hasValue());
306 EXPECT_EQ("hello", b.value());
309 EXPECT_TRUE(a.hasValue());
310 EXPECT_EQ("bye", a.value());
315 TEST(Optional, Comparisons) {
320 EXPECT_TRUE(o_ <= (o_));
321 EXPECT_TRUE(o_ == (o_));
322 EXPECT_TRUE(o_ >= (o_));
324 EXPECT_TRUE(o1 < o2);
325 EXPECT_TRUE(o1 <= o2);
326 EXPECT_TRUE(o1 <= (o1));
327 EXPECT_TRUE(o1 == (o1));
328 EXPECT_TRUE(o1 != o2);
329 EXPECT_TRUE(o1 >= (o1));
330 EXPECT_TRUE(o2 >= o1);
331 EXPECT_TRUE(o2 > o1);
333 EXPECT_FALSE(o2 < o1);
334 EXPECT_FALSE(o2 <= o1);
335 EXPECT_FALSE(o2 <= o1);
336 EXPECT_FALSE(o2 == o1);
337 EXPECT_FALSE(o1 != (o1));
338 EXPECT_FALSE(o1 >= o2);
339 EXPECT_FALSE(o1 >= o2);
340 EXPECT_FALSE(o1 > o2);
342 /* folly::Optional explicitly doesn't support comparisons with contained value
344 EXPECT_TRUE(1 <= o2);
345 EXPECT_TRUE(1 <= o1);
346 EXPECT_TRUE(1 == o1);
347 EXPECT_TRUE(2 != o1);
348 EXPECT_TRUE(1 >= o1);
349 EXPECT_TRUE(2 >= o1);
352 EXPECT_FALSE(o2 < 1);
353 EXPECT_FALSE(o2 <= 1);
354 EXPECT_FALSE(o2 <= 1);
355 EXPECT_FALSE(o2 == 1);
356 EXPECT_FALSE(o2 != 2);
357 EXPECT_FALSE(o1 >= 2);
358 EXPECT_FALSE(o1 >= 2);
359 EXPECT_FALSE(o1 > 2);
362 // boost::optional does support comparison with contained value, which can
363 // lead to confusion when a bool is contained
364 boost::optional<int> boi(3);
365 EXPECT_TRUE(boi < 5);
366 EXPECT_TRUE(boi <= 4);
367 EXPECT_TRUE(boi == 3);
368 EXPECT_TRUE(boi != 2);
369 EXPECT_TRUE(boi >= 1);
370 EXPECT_TRUE(boi > 0);
371 EXPECT_TRUE(1 < boi);
372 EXPECT_TRUE(2 <= boi);
373 EXPECT_TRUE(3 == boi);
374 EXPECT_TRUE(4 != boi);
375 EXPECT_TRUE(5 >= boi);
376 EXPECT_TRUE(6 > boi);
378 boost::optional<bool> bob(false);
379 EXPECT_TRUE((bool)bob);
380 EXPECT_TRUE(bob == false); // well that was confusing
381 EXPECT_FALSE(bob != false);
384 TEST(Optional, Conversions) {
385 Optional<bool> mbool;
386 Optional<short> mshort;
387 Optional<char*> mstr;
390 //These don't compile
399 // intended explicit operator bool, for if (opt).
402 // Truthy tests work and are not ambiguous
403 if (mbool && mshort && mstr && mint) { // only checks not-empty
404 if (*mbool && *mshort && *mstr && *mint) { // only checks value
410 EXPECT_TRUE(bool(mbool));
411 EXPECT_FALSE(*mbool);
414 EXPECT_TRUE(bool(mbool));
418 EXPECT_FALSE(bool(mbool));
420 // No conversion allowed; does not compile
421 // EXPECT_TRUE(mbool == false);
424 TEST(Optional, Pointee) {
426 EXPECT_FALSE(get_pointer(x));
428 EXPECT_TRUE(get_pointer(x));
430 EXPECT_TRUE(*x == 2);
432 EXPECT_FALSE(get_pointer(x));
435 TEST(Optional, MakeOptional) {
436 // const L-value version
437 const std::string s("abc");
438 auto optStr = make_optional(s);
439 ASSERT_TRUE(optStr.hasValue());
440 EXPECT_EQ(*optStr, "abc");
443 EXPECT_EQ(*optStr, "cde");
446 std::string s2("abc");
447 auto optStr2 = make_optional(s2);
448 ASSERT_TRUE(optStr2.hasValue());
449 EXPECT_EQ(*optStr2, "abc");
451 // it's vital to check that s2 wasn't clobbered
452 EXPECT_EQ(s2, "abc");
454 // L-value reference version
456 auto optStr3 = make_optional(s3);
457 ASSERT_TRUE(optStr3.hasValue());
458 EXPECT_EQ(*optStr3, "abc");
460 EXPECT_EQ(s3, "abc");
462 // R-value ref version
463 unique_ptr<int> pInt(new int(3));
464 auto optIntPtr = make_optional(std::move(pInt));
465 EXPECT_TRUE(pInt.get() == nullptr);
466 ASSERT_TRUE(optIntPtr.hasValue());
467 EXPECT_EQ(**optIntPtr, 3);
471 # pragma clang diagnostic push
472 # if __clang_major__ > 3 || __clang_minor__ >= 6
473 # pragma clang diagnostic ignored "-Wself-move"
477 TEST(Optional, SelfAssignment) {
478 Optional<int> a = 42;
480 ASSERT_TRUE(a.hasValue() && a.value() == 42);
482 Optional<int> b = 23333333;
484 ASSERT_TRUE(b.hasValue() && b.value() == 23333333);
488 #pragma clang diagnostic pop
491 class ContainsOptional {
493 ContainsOptional() { }
494 explicit ContainsOptional(int x) : opt_(x) { }
495 bool hasValue() const { return opt_.hasValue(); }
496 int value() const { return opt_.value(); }
498 ContainsOptional(const ContainsOptional &other) = default;
499 ContainsOptional& operator=(const ContainsOptional &other) = default;
500 ContainsOptional(ContainsOptional &&other) = default;
501 ContainsOptional& operator=(ContainsOptional &&other) = default;
508 * Test that a class containing an Optional can be copy and move assigned.
509 * This was broken under gcc 4.7 until assignment operators were explicitly
512 TEST(Optional, AssignmentContained) {
514 ContainsOptional source(5), target;
516 EXPECT_TRUE(target.hasValue());
517 EXPECT_EQ(5, target.value());
521 ContainsOptional source(5), target;
522 target = std::move(source);
523 EXPECT_TRUE(target.hasValue());
524 EXPECT_EQ(5, target.value());
525 EXPECT_FALSE(source.hasValue());
529 ContainsOptional opt_uninit, target(10);
531 EXPECT_FALSE(target.hasValue());
535 TEST(Optional, Exceptions) {
537 EXPECT_THROW(empty.value(), OptionalEmptyException);