1///////////////////////////////////////////////////////////////////////////////
2//
3// Copyright (c) 2015 Microsoft Corporation. All rights reserved.
4//
5// This code is licensed under the MIT License (MIT).
6//
7// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
8// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
9// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
10// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
11// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
12// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
13// THE SOFTWARE.
14//
15///////////////////////////////////////////////////////////////////////////////
16
17#include <UnitTest++/UnitTest++.h>
18#include <gsl/gsl>
19#include <vector>
20
21using namespace gsl;
22
23struct MyBase {};
24struct MyDerived : public MyBase {};
25struct Unrelated {};
26
27// stand-in for a user-defined ref-counted class
28template<typename T>
29struct RefCounted
30{
31    RefCounted(T* p) : p_(p) {}
32    operator T*() { return p_; }
33    T* p_;
34};
35
36SUITE(NotNullTests)
37{
38
39    bool helper(not_null<int*> p)
40    {
41        return *p == 12;
42    }
43
44    TEST(TestNotNullConstructors)
45    {
46#ifdef CONFIRM_COMPILATION_ERRORS
47        not_null<int*> p = nullptr; // yay...does not compile!
48        not_null<std::vector<char>*> p = 0; // yay...does not compile!
49        not_null<int*> p; // yay...does not compile!
50        std::unique_ptr<int> up = std::make_unique<int>(120);
51        not_null<int*> p = up;
52
53        // Forbid non-nullptr assignable types
54        not_null<std::vector<int>> f(std::vector<int>{1});
55        not_null<int> z(10);
56        not_null<std::vector<int>> y({1,2});
57#endif
58      int i = 12;
59      auto rp = RefCounted<int>(&i);
60      not_null<int*> p(rp);
61      CHECK(p.get() == &i);
62
63      not_null<std::shared_ptr<int>> x(std::make_shared<int>(10)); // shared_ptr<int> is nullptr assignable
64    }
65
66    TEST(TestNotNullCasting)
67    {
68        MyBase base;
69	MyDerived derived;
70	Unrelated unrelated;
71	not_null<Unrelated*> u = &unrelated;
72        (void)u;
73	not_null<MyDerived*> p = &derived;
74        not_null<MyBase*> q = &base;
75	q = p; // allowed with heterogeneous copy ctor
76        CHECK(q == p);
77
78#ifdef CONFIRM_COMPILATION_ERRORS
79	q = u; // no viable conversion possible between MyBase* and Unrelated*
80	p = q; // not possible to implicitly convert MyBase* to MyDerived*
81
82        not_null<Unrelated*> r = p;
83        not_null<Unrelated*> s = reinterpret_cast<Unrelated*>(p);
84#endif
85        not_null<Unrelated*> t = reinterpret_cast<Unrelated*>(p.get());
86        CHECK((void*)p.get() == (void*)t.get());
87    }
88
89    TEST(TestNotNullAssignment)
90    {
91        int i = 12;
92        not_null<int*> p = &i;
93        CHECK(helper(p));
94
95        int* q = nullptr;
96        CHECK_THROW(p = q, fail_fast);
97    }
98}
99
100int main(int, const char *[])
101{
102    return UnitTest::RunAllTests();
103}
104