LSSTApplications  19.0.0-14-gb0260a2+64befe7c1c,20.0.0+0b340dd7c4,20.0.0+1540ce6389,20.0.0+7c6b12c2f9,20.0.0+ae956f52c5,20.0.0+be870186d9,20.0.0+e2e26847c2,20.0.0-1-g04bee24+7c6b12c2f9,20.0.0-1-g10df615+fbe45b1aff,20.0.0-1-g253301a+7c6b12c2f9,20.0.0-1-g2b7511a+46a6078777,20.0.0-1-g4d801e7+9d50d6c21a,20.0.0-1-g5b95a8c+8ebfc75efb,20.0.0-1-gb058bd0+46a6078777,20.0.0-1-gb88604f+acecce4127,20.0.0-1-gc96f8cb+016e330d09,20.0.0-1-gedffbd8+83814edeba,20.0.0-10-g0891cd99+a5f14e9acb,20.0.0-10-g9a20bd332+576ca7b471,20.0.0-17-gcdbda88+0e26bfb1e6,20.0.0-2-g4dae9ad+016e330d09,20.0.0-2-g61b8584+85c46248f3,20.0.0-2-gb780d76+f45b7d88f4,20.0.0-21-g9bbb7f7+016e330d09,20.0.0-22-gc512666+f30f3883a7,20.0.0-23-g8900aa8+68630f7098,20.0.0-3-g1653f94+85c46248f3,20.0.0-3-g4cc78c6+63636aeed8,20.0.0-3-g750bffe+e05f822de9,20.0.0-3-gbd60e8c+ff10c6d78d,20.0.0-32-g15a0e07c+a4c9d0309b,20.0.0-4-g97dc21a+68630f7098,20.0.0-4-gfea843c+f45b7d88f4,20.0.0-5-g357b56b+f45b7d88f4,20.0.0-6-g9a5b7a1+b0f8c2be93,20.0.0-60-gad89340+e4dd172200,20.0.0-7-gcda7bf1+673816f70c,w.2020.43
LSSTDataManagementBasePackage
tests.h
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1 // -*- lsst-c++ -*-
2 
3 /*
4  * This file is part of utils.
5  *
6  * Developed for the LSST Data Management System.
7  * This product includes software developed by the LSST Project
8  * (https://www.lsst.org).
9  * See the COPYRIGHT file at the top-level directory of this distribution
10  * for details of code ownership.
11  *
12  * This program is free software: you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation, either version 3 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program. If not, see <https://www.gnu.org/licenses/>.
24  */
25 
26 #ifndef LSST_UTILS_TESTS_H
27 #define LSST_UTILS_TESTS_H
28 
29 // Do not include unit_test.hpp, to avoid definition problems with BOOST_TEST_MODULE
30 
31 #include <ostream>
32 #include <type_traits>
33 
34 namespace lsst {
35 namespace utils {
36 
37 namespace {
38 // Variable template reporting whether a type can be printed using <<
39 // Second template parameter is a dummy to let us do some metaprogramming
40 template <typename, typename = void>
41 constexpr bool HAS_STREAM_OUTPUT = false;
42 template <typename T>
43 constexpr bool HAS_STREAM_OUTPUT<
44  T, std::enable_if_t<true, decltype((void)(std::declval<std::ostream&>() << std::declval<T&>()),
45  void())>> = true;
46 
47 // Conditional function templates reporting object values if possible
48 template <typename T, class Hash>
49 std::enable_if_t<HAS_STREAM_OUTPUT<T>> printIfHashEqual(T obj1, T obj2, Hash hash) {
50  BOOST_TEST_REQUIRE(obj1 == obj2);
51  BOOST_TEST(hash(obj1) == hash(obj2),
52  obj1 << " == " << obj2 << ", but " << hash(obj1) << " != " << hash(obj2));
53 }
54 template <typename T, class Hash>
55 std::enable_if_t<!HAS_STREAM_OUTPUT<T>> printIfHashEqual(T obj1, T obj2, Hash hash) {
56  if (!(obj1 == obj2)) {
57  BOOST_FAIL("Unequal objects need not have equal hashes.");
58  }
59  BOOST_TEST(hash(obj1) == hash(obj2));
60 }
61 } // namespace
62 
71 template <typename T>
72 constexpr void assertValidHash() {
73  using namespace std;
74  using Hash = hash<remove_cv_t<T>>;
75 
77  "std::hash specializations must be default-constructible");
78  static_assert(is_copy_assignable<Hash>::value, "std::hash specializations must be copy-assignable");
79  // Swappability hard to test before C++17
80  static_assert(is_destructible<Hash>::value, "std::hash specializations must be destructible");
81 
82  static_assert(is_same<typename Hash::argument_type, remove_cv_t<T>>::value,
83  "std::hash must have an argument_type member until C++20");
85  "std::hash must have a result_type member until C++20");
86  // Ability to call Hash(T) hard to test before C++17
87  static_assert(is_same<result_of_t<Hash(T)>, size_t>::value,
88  "std::hash specializations must be callable and return a size_t");
89 }
90 
101 template <typename T>
102 void assertHashesEqual(T obj1, T obj2) {
103  using Hash = std::hash<std::remove_cv_t<T>>;
104 
105  printIfHashEqual(obj1, obj2, Hash());
106 }
107 
108 } // namespace utils
109 } // namespace lsst
110 
111 #endif
std::is_same
std::is_destructible
std::is_default_constructible
lsst::utils::assertHashesEqual
void assertHashesEqual(T obj1, T obj2)
Test that equal objects have equal hashes.
Definition: tests.h:102
lsst::utils::assertValidHash
constexpr void assertValidHash()
Compile-time test of whether a specialization of std::hash conforms to the general spec.
Definition: tests.h:72
lsst
A base class for image defects.
Definition: imageAlgorithm.dox:1
std
STL namespace.
std::is_copy_assignable
std::hash