GSL/tests/notnull_tests.cpp
Anna Gringauze 9ff6e19ea9
Dev/annagrin/remove explicit not null constructor (#743)
* Added c++17 test configurations for clang5.0 and clang6.0

* Removed explicit not_null constructor, sloppy_not_null, added strict_not_null

We added explicit not_null constructor in version 2.0.0.
It proved very difficult to switch to the new version for
large code bases that adopted previous versions of gsl,
due to not_null used extensively in the code. Still, using
explicit constructor is very benefitial for new code, since
it encorages better API design and make null checks intentional.

To resolve the issue, this change:
- removes explicit keyword from not_null constructor
- removes unneded sloppy_not_null type
- adds strict_not_null type to behave the same way as v2 not_null
- updates tests

* Removed explicit not_null constructor, sloppy_not_null, added strict_not_null

We added explicit not_null constructor in version 2.0.0.
It proved very difficult to switch to the new version for
large code bases that adopted previous versions of gsl,
due to not_null used extensively in the code. Still, using
explicit constructor is very benefitial for new code, since
it encorages better API design and make null checks intentional.

To resolve the issue, this change:
- removes explicit keyword from not_null constructor
- removes unneded sloppy_not_null type
- adds strict_not_null type to behave the same way as v2 not_null
- updates tests

* fixed build break for gcc7

* added more tests

* added more non-compiling tests

* Addressed PR comments and suppressed a code analysis warning

* Fixed test failure in not_null tests
2019-01-14 16:45:47 -08:00

537 lines
15 KiB
C++

///////////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2015 Microsoft Corporation. All rights reserved.
//
// This code is licensed under the MIT License (MIT).
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//
///////////////////////////////////////////////////////////////////////////////
#ifdef _MSC_VER
// blanket turn off warnings from CppCoreCheck from catch
// so people aren't annoyed by them when running the tool.
#pragma warning(disable : 26440 26426) // from catch
// Fix VS2015 build breaks in Release
#pragma warning(disable : 4702) // unreachable code
#endif
#include <catch/catch.hpp> // for AssertionHandler, StringRef, CHECK, TEST_...
#include <gsl/pointers> // for not_null, operator<, operator<=, operator>
#include <algorithm> // for addressof
#include <memory> // for shared_ptr, make_shared, operator<, opera...
#include <sstream> // for operator<<, ostringstream, basic_ostream:...
#include <stdint.h> // for uint16_t
#include <string> // for basic_string, operator==, string, operator<<
#include <typeinfo> // for type_info
namespace gsl
{
struct fail_fast;
} // namespace gsl
using namespace gsl;
struct MyBase
{
};
struct MyDerived : public MyBase
{
};
struct Unrelated
{
};
// stand-in for a user-defined ref-counted class
template <typename T>
struct RefCounted
{
RefCounted(T* p) : p_(p) {}
operator T*() { return p_; }
T* p_;
};
// user defined smart pointer with comparison operators returning non bool value
template <typename T>
struct CustomPtr
{
CustomPtr(T* p) : p_(p) {}
operator T*() { return p_; }
bool operator!=(std::nullptr_t) const { return p_ != nullptr; }
T* p_ = nullptr;
};
template <typename T, typename U>
std::string operator==(CustomPtr<T> const& lhs, CustomPtr<U> const& rhs)
{
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
return reinterpret_cast<const void*>(lhs.p_) == reinterpret_cast<const void*>(rhs.p_) ? "true"
: "false";
}
template <typename T, typename U>
std::string operator!=(CustomPtr<T> const& lhs, CustomPtr<U> const& rhs)
{
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
return reinterpret_cast<const void*>(lhs.p_) != reinterpret_cast<const void*>(rhs.p_) ? "true"
: "false";
}
template <typename T, typename U>
std::string operator<(CustomPtr<T> const& lhs, CustomPtr<U> const& rhs)
{
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
return reinterpret_cast<const void*>(lhs.p_) < reinterpret_cast<const void*>(rhs.p_) ? "true"
: "false";
}
template <typename T, typename U>
std::string operator>(CustomPtr<T> const& lhs, CustomPtr<U> const& rhs)
{
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
return reinterpret_cast<const void*>(lhs.p_) > reinterpret_cast<const void*>(rhs.p_) ? "true"
: "false";
}
template <typename T, typename U>
std::string operator<=(CustomPtr<T> const& lhs, CustomPtr<U> const& rhs)
{
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
return reinterpret_cast<const void*>(lhs.p_) <= reinterpret_cast<const void*>(rhs.p_) ? "true"
: "false";
}
template <typename T, typename U>
std::string operator>=(CustomPtr<T> const& lhs, CustomPtr<U> const& rhs)
{
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
return reinterpret_cast<const void*>(lhs.p_) >= reinterpret_cast<const void*>(rhs.p_) ? "true"
: "false";
}
struct NonCopyableNonMovable
{
NonCopyableNonMovable() = default;
NonCopyableNonMovable(const NonCopyableNonMovable&) = delete;
NonCopyableNonMovable& operator=(const NonCopyableNonMovable&) = delete;
NonCopyableNonMovable(NonCopyableNonMovable&&) = delete;
NonCopyableNonMovable& operator=(NonCopyableNonMovable&&) = delete;
};
GSL_SUPPRESS(f.4) // NO-FORMAT: attribute
bool helper(not_null<int*> p) { return *p == 12; }
GSL_SUPPRESS(f.4) // NO-FORMAT: attribute
bool helper_const(not_null<const int*> p) { return *p == 12; }
int* return_pointer() { return nullptr; }
const int* return_pointer_const() { return nullptr; }
GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
TEST_CASE("TestNotNullConstructors")
{
{
#ifdef CONFIRM_COMPILATION_ERRORS
not_null<int*> p = nullptr; // yay...does not compile!
not_null<std::vector<char>*> p1 = 0; // yay...does not compile!
not_null<int*> p2; // yay...does not compile!
std::unique_ptr<int> up = std::make_unique<int>(120);
not_null<int*> p3 = up;
// Forbid non-nullptr assignable types
not_null<std::vector<int>> f(std::vector<int>{1});
not_null<int> z(10);
not_null<std::vector<int>> y({1, 2});
#endif
}
{
// from shared pointer
int i = 12;
auto rp = RefCounted<int>(&i);
not_null<int*> p(rp);
CHECK(p.get() == &i);
not_null<std::shared_ptr<int>> x(
std::make_shared<int>(10)); // shared_ptr<int> is nullptr assignable
int* pi = nullptr;
CHECK_THROWS_AS(not_null<decltype(pi)>(pi), fail_fast);
}
{
// from pointer to local
int t = 42;
not_null<int*> x = &t;
helper(&t);
helper_const(&t);
CHECK(*x == 42);
}
{
// from raw pointer
// from not_null pointer
int t = 42;
int* p = &t;
not_null<int*> x = p;
helper(p);
helper_const(p);
helper(x);
helper_const(x);
CHECK(*x == 42);
}
{
// from raw const pointer
// from not_null const pointer
int t = 42;
const int* cp = &t;
not_null<const int*> x = cp;
helper_const(cp);
helper_const(x);
CHECK(*x == 42);
}
{
// from not_null const pointer, using auto
int t = 42;
const int* cp = &t;
auto x = not_null<const int*>{cp};
CHECK(*x == 42);
}
{
// from returned pointer
CHECK_THROWS_AS(helper(return_pointer()), fail_fast);
CHECK_THROWS_AS(helper_const(return_pointer()), fail_fast);
}
}
template <typename T>
GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
void ostream_helper(T v)
{
not_null<T*> p(&v);
{
std::ostringstream os;
std::ostringstream ref;
os << p;
ref << &v;
CHECK(os.str() == ref.str());
}
{
std::ostringstream os;
std::ostringstream ref;
os << *p;
ref << v;
CHECK(os.str() == ref.str());
}
}
TEST_CASE("TestNotNullostream")
{
ostream_helper<int>(17);
ostream_helper<float>(21.5f);
ostream_helper<double>(3.4566e-7f);
ostream_helper<char>('c');
ostream_helper<uint16_t>(0x0123u);
ostream_helper<const char*>("cstring");
ostream_helper<std::string>("string");
}
GSL_SUPPRESS(type.1) // NO-FORMAT: attribute
GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
TEST_CASE("TestNotNullCasting")
{
MyBase base;
MyDerived derived;
Unrelated unrelated;
not_null<Unrelated*> u{&unrelated};
(void) u;
not_null<MyDerived*> p{&derived};
not_null<MyBase*> q(&base);
q = p; // allowed with heterogeneous copy ctor
CHECK(q == p);
#ifdef CONFIRM_COMPILATION_ERRORS
q = u; // no viable conversion possible between MyBase* and Unrelated*
p = q; // not possible to implicitly convert MyBase* to MyDerived*
not_null<Unrelated*> r = p;
not_null<Unrelated*> s = reinterpret_cast<Unrelated*>(p);
#endif
not_null<Unrelated*> t(reinterpret_cast<Unrelated*>(p.get()));
CHECK(reinterpret_cast<void*>(p.get()) == reinterpret_cast<void*>(t.get()));
}
TEST_CASE("TestNotNullAssignment")
{
int i = 12;
not_null<int*> p(&i);
CHECK(helper(p));
int* q = nullptr;
CHECK_THROWS_AS(p = not_null<int*>(q), fail_fast);
}
TEST_CASE("TestNotNullRawPointerComparison")
{
int ints[2] = {42, 43};
int* p1 = &ints[0];
const int* p2 = &ints[1];
using NotNull1 = not_null<decltype(p1)>;
using NotNull2 = not_null<decltype(p2)>;
CHECK((NotNull1(p1) == NotNull1(p1)) == true);
CHECK((NotNull1(p1) == NotNull2(p2)) == false);
CHECK((NotNull1(p1) != NotNull1(p1)) == false);
CHECK((NotNull1(p1) != NotNull2(p2)) == true);
CHECK((NotNull1(p1) < NotNull1(p1)) == false);
CHECK((NotNull1(p1) < NotNull2(p2)) == (p1 < p2));
CHECK((NotNull2(p2) < NotNull1(p1)) == (p2 < p1));
CHECK((NotNull1(p1) > NotNull1(p1)) == false);
CHECK((NotNull1(p1) > NotNull2(p2)) == (p1 > p2));
CHECK((NotNull2(p2) > NotNull1(p1)) == (p2 > p1));
CHECK((NotNull1(p1) <= NotNull1(p1)) == true);
CHECK((NotNull1(p1) <= NotNull2(p2)) == (p1 <= p2));
CHECK((NotNull2(p2) <= NotNull1(p1)) == (p2 <= p1));
}
GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
TEST_CASE("TestNotNullDereferenceOperator")
{
{
auto sp1 = std::make_shared<NonCopyableNonMovable>();
using NotNullSp1 = not_null<decltype(sp1)>;
CHECK(typeid(*sp1) == typeid(*NotNullSp1(sp1)));
CHECK(std::addressof(*NotNullSp1(sp1)) == std::addressof(*sp1));
}
{
int ints[1] = {42};
CustomPtr<int> p1(&ints[0]);
using NotNull1 = not_null<decltype(p1)>;
CHECK(typeid(*NotNull1(p1)) == typeid(*p1));
CHECK(*NotNull1(p1) == 42);
*NotNull1(p1) = 43;
CHECK(ints[0] == 43);
}
{
int v = 42;
gsl::not_null<int*> p(&v);
CHECK(typeid(*p) == typeid(*(&v)));
*p = 43;
CHECK(v == 43);
}
}
TEST_CASE("TestNotNullSharedPtrComparison")
{
auto sp1 = std::make_shared<int>(42);
auto sp2 = std::make_shared<const int>(43);
using NotNullSp1 = not_null<decltype(sp1)>;
using NotNullSp2 = not_null<decltype(sp2)>;
CHECK((NotNullSp1(sp1) == NotNullSp1(sp1)) == true);
CHECK((NotNullSp1(sp1) == NotNullSp2(sp2)) == false);
CHECK((NotNullSp1(sp1) != NotNullSp1(sp1)) == false);
CHECK((NotNullSp1(sp1) != NotNullSp2(sp2)) == true);
CHECK((NotNullSp1(sp1) < NotNullSp1(sp1)) == false);
CHECK((NotNullSp1(sp1) < NotNullSp2(sp2)) == (sp1 < sp2));
CHECK((NotNullSp2(sp2) < NotNullSp1(sp1)) == (sp2 < sp1));
CHECK((NotNullSp1(sp1) > NotNullSp1(sp1)) == false);
CHECK((NotNullSp1(sp1) > NotNullSp2(sp2)) == (sp1 > sp2));
CHECK((NotNullSp2(sp2) > NotNullSp1(sp1)) == (sp2 > sp1));
CHECK((NotNullSp1(sp1) <= NotNullSp1(sp1)) == true);
CHECK((NotNullSp1(sp1) <= NotNullSp2(sp2)) == (sp1 <= sp2));
CHECK((NotNullSp2(sp2) <= NotNullSp1(sp1)) == (sp2 <= sp1));
CHECK((NotNullSp1(sp1) >= NotNullSp1(sp1)) == true);
CHECK((NotNullSp1(sp1) >= NotNullSp2(sp2)) == (sp1 >= sp2));
CHECK((NotNullSp2(sp2) >= NotNullSp1(sp1)) == (sp2 >= sp1));
}
GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
TEST_CASE("TestNotNullCustomPtrComparison")
{
int ints[2] = {42, 43};
CustomPtr<int> p1(&ints[0]);
CustomPtr<const int> p2(&ints[1]);
using NotNull1 = not_null<decltype(p1)>;
using NotNull2 = not_null<decltype(p2)>;
CHECK((NotNull1(p1) == NotNull1(p1)) == "true");
CHECK((NotNull1(p1) == NotNull2(p2)) == "false");
CHECK((NotNull1(p1) != NotNull1(p1)) == "false");
CHECK((NotNull1(p1) != NotNull2(p2)) == "true");
CHECK((NotNull1(p1) < NotNull1(p1)) == "false");
CHECK((NotNull1(p1) < NotNull2(p2)) == (p1 < p2));
CHECK((NotNull2(p2) < NotNull1(p1)) == (p2 < p1));
CHECK((NotNull1(p1) > NotNull1(p1)) == "false");
CHECK((NotNull1(p1) > NotNull2(p2)) == (p1 > p2));
CHECK((NotNull2(p2) > NotNull1(p1)) == (p2 > p1));
CHECK((NotNull1(p1) <= NotNull1(p1)) == "true");
CHECK((NotNull1(p1) <= NotNull2(p2)) == (p1 <= p2));
CHECK((NotNull2(p2) <= NotNull1(p1)) == (p2 <= p1));
CHECK((NotNull1(p1) >= NotNull1(p1)) == "true");
CHECK((NotNull1(p1) >= NotNull2(p2)) == (p1 >= p2));
CHECK((NotNull2(p2) >= NotNull1(p1)) == (p2 >= p1));
}
#if defined(__cplusplus) && (__cplusplus >= 201703L)
GSL_SUPPRESS(con.4) // NO-FORMAT: attribute
TEST_CASE("TestNotNullConstructorTypeDeduction")
{
{
int i = 42;
not_null x{&i};
helper(not_null{&i});
helper_const(not_null{&i});
CHECK(*x == 42);
}
{
int i = 42;
int* p = &i;
not_null x{p};
helper(not_null{p});
helper_const(not_null{p});
CHECK(*x == 42);
}
{
auto workaround_macro = []() {
int* p1 = nullptr;
const not_null x{p1};
};
CHECK_THROWS_AS(workaround_macro(), fail_fast);
}
{
auto workaround_macro = []() {
const int* p1 = nullptr;
const not_null x{p1};
};
CHECK_THROWS_AS(workaround_macro(), fail_fast);
}
{
int* p = nullptr;
CHECK_THROWS_AS(helper(not_null{p}), fail_fast);
CHECK_THROWS_AS(helper_const(not_null{p}), fail_fast);
}
#ifdef CONFIRM_COMPILATION_ERRORS
{
not_null x{nullptr};
helper(not_null{nullptr});
helper_const(not_null{nullptr});
}
#endif
}
#endif // #if defined(__cplusplus) && (__cplusplus >= 201703L)
TEST_CASE("TestMakeNotNull")
{
{
int i = 42;
const auto x = make_not_null(&i);
helper(make_not_null(&i));
helper_const(make_not_null(&i));
CHECK(*x == 42);
}
{
int i = 42;
int* p = &i;
const auto x = make_not_null(p);
helper(make_not_null(p));
helper_const(make_not_null(p));
CHECK(*x == 42);
}
{
const auto workaround_macro = []() {
int* p1 = nullptr;
const auto x = make_not_null(p1);
CHECK(*x == 42);
};
CHECK_THROWS_AS(workaround_macro(), fail_fast);
}
{
const auto workaround_macro = []() {
const int* p1 = nullptr;
const auto x = make_not_null(p1);
CHECK(*x == 42);
};
CHECK_THROWS_AS(workaround_macro(), fail_fast);
}
{
int* p = nullptr;
CHECK_THROWS_AS(helper(make_not_null(p)), fail_fast);
CHECK_THROWS_AS(helper_const(make_not_null(p)), fail_fast);
}
#ifdef CONFIRM_COMPILATION_ERRORS
{
CHECK_THROWS_AS(make_not_null(nullptr), fail_fast);
CHECK_THROWS_AS(helper(make_not_null(nullptr)), fail_fast);
CHECK_THROWS_AS(helper_const(make_not_null(nullptr)), fail_fast);
}
#endif
}
static_assert(std::is_nothrow_move_constructible<not_null<void*>>::value,
"not_null must be no-throw move constructible");