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Merge pull request #2 from Microsoft/master

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Updating the fork
This commit is contained in:
Samuel García 2015-11-13 19:33:02 +01:00
commit 70e735b911
12 changed files with 2689 additions and 2756 deletions
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13
.gitignore vendored
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@ -1 +1,14 @@
tests/unittest-cpp
CMakeFiles
tests/CMakeFiles
tests/Debug
*.opensdf
*.sdf
tests/*tests.dir
*.vcxproj
*.vcxproj.filters
*.sln
*.tlog
Testing/Temporary/*.*
CMakeCache.txt
*.suo

6
README.md
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@ -4,11 +4,11 @@ The Guidelines Support Library (GSL) contains functions and types that are sugge
[C++ Core Guidelines](https://github.com/isocpp/CppCoreGuidelines) maintained by the [Standard C++ Foundation](https://isocpp.org).
This repo contains Microsoft's implementation of GSL.
The library includes types like `array_view<>`, `string_view<>`, `owner<>` and others.
The library includes types like `span<T>`, `string_span`, `owner<>` and others.
The entire implementation is provided inline in the headers under the [include](./include) directory.
The entire implementation is provided inline in the headers under the [include](./include) directory. The implementation generally assumes a platform that implements C++14 support. There are specific workarounds to support MSVC 2013 and 2015.
While some types have been broken out into their own headers (e.g. [include/array_view.h](./include/array_view.h)),
While some types have been broken out into their own headers (e.g. [include/span.h](./include/span.h)),
it is simplest to just include [gsl.h](./include/gsl.h) and gain access to the entire library.
> NOTE: We encourage contributions that improve or refine any of the types in this library as well as ports to

1998
include/array_view.h
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4
include/gsl.h
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@ -19,8 +19,8 @@
#ifndef GSL_GSL_H
#define GSL_GSL_H
#include "array_view.h" // array_view, strided_array_view...
#include "string_view.h" // zstring, string_view, zstring_builder...
#include "span.h" // span, strided_span...
#include "string_span.h" // zstring, string_span, zstring_builder...
#include <memory>
#ifdef _MSC_VER

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include/span.h Normal file
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227
include/string_span.h Normal file
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@ -0,0 +1,227 @@
///////////////////////////////////////////////////////////////////////////////
//
// 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.
//
///////////////////////////////////////////////////////////////////////////////
#pragma once
#ifndef GSL_STRING_SPAN_H
#define GSL_STRING_SPAN_H
#include "span.h"
#include <cstring>
// VS 2013 workarounds
#ifdef _MSC_VER
#if _MSC_VER <= 1800
#pragma push_macro("GSL_MSVC_HAS_TYPE_DEDUCTION_BUG")
#define GSL_MSVC_HAS_TYPE_DEDUCTION_BUG
#endif // _MSC_VER <= 1800
#endif // _MSC_VER
namespace gsl
{
//
// czstring and wzstring
//
// These are "tag" typedef's for C-style strings (i.e. null-terminated character arrays)
// that allow static analysis to help find bugs.
//
// There are no additional features/semantics that we can find a way to add inside the
// type system for these types that will not either incur significant runtime costs or
// (sometimes needlessly) break existing programs when introduced.
//
template<std::ptrdiff_t Extent = dynamic_range>
using czstring = const char*;
template<std::ptrdiff_t Extent = dynamic_range>
using cwzstring = const wchar_t*;
template<std::ptrdiff_t Extent = dynamic_range>
using zstring = char*;
template<std::ptrdiff_t Extent = dynamic_range>
using wzstring = wchar_t*;
//
// string_span and relatives
//
// Note that Extent is always single-dimension only
//
template <class CharT, std::ptrdiff_t Extent = dynamic_range>
using basic_string_span = span<CharT, Extent>;
template<std::ptrdiff_t Extent = dynamic_range>
using string_span = basic_string_span<char, Extent>;
template<std::ptrdiff_t Extent = dynamic_range>
using cstring_span = basic_string_span<const char, Extent>;
template<std::ptrdiff_t Extent = dynamic_range>
using wstring_span = basic_string_span<wchar_t, Extent>;
template<std::ptrdiff_t Extent = dynamic_range>
using cwstring_span = basic_string_span<const wchar_t, Extent>;
//
// ensure_sentinel()
//
// Provides a way to obtain an span from a contiguous sequence
// that ends with a (non-inclusive) sentinel value.
//
// Will fail-fast if sentinel cannot be found before max elements are examined.
//
template<class T, const T Sentinel>
span<T, dynamic_range> ensure_sentinel(const T* seq, std::ptrdiff_t max = PTRDIFF_MAX)
{
auto cur = seq;
while ((cur - seq) < max && *cur != Sentinel) ++cur;
fail_fast_assert(*cur == Sentinel);
return{ seq, cur - seq };
}
//
// ensure_z - creates a string_span for a czstring or cwzstring.
// Will fail fast if a null-terminator cannot be found before
// the limit of size_type.
//
template<class T>
inline basic_string_span<T, dynamic_range> ensure_z(T* const & sz, std::ptrdiff_t max = PTRDIFF_MAX)
{
return ensure_sentinel<T, 0>(sz, max);
}
// TODO (neilmac) there is probably a better template-magic way to get the const and non-const overloads to share an implementation
inline basic_string_span<char, dynamic_range> ensure_z(char* const& sz, std::ptrdiff_t max)
{
auto len = strnlen(sz, max);
fail_fast_assert(sz[len] == 0);
return{ sz, static_cast<std::ptrdiff_t>(len) };
}
inline basic_string_span<const char, dynamic_range> ensure_z(const char* const& sz, std::ptrdiff_t max)
{
auto len = strnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, static_cast<std::ptrdiff_t>(len) };
}
inline basic_string_span<wchar_t, dynamic_range> ensure_z(wchar_t* const& sz, std::ptrdiff_t max)
{
auto len = wcsnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, static_cast<std::ptrdiff_t>(len) };
}
inline basic_string_span<const wchar_t, dynamic_range> ensure_z(const wchar_t* const& sz, std::ptrdiff_t max)
{
auto len = wcsnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, static_cast<std::ptrdiff_t>(len) };
}
template<class T, size_t N>
basic_string_span<T, dynamic_range> ensure_z(T(&sz)[N]) { return ensure_z(&sz[0], static_cast<std::ptrdiff_t>(N)); }
template<class Cont>
basic_string_span<typename std::remove_pointer<typename Cont::pointer>::type, dynamic_range> ensure_z(Cont& cont)
{
return ensure_z(cont.data(), static_cast<std::ptrdiff_t>(cont.length()));
}
//
// to_string() allow (explicit) conversions from string_span to string
//
#ifndef GSL_MSVC_HAS_TYPE_DEDUCTION_BUG
template<class CharT, ptrdiff_t Extent>
std::basic_string<typename std::remove_const<CharT>::type> to_string(basic_string_span<CharT, Extent> view)
{
return{ view.data(), static_cast<size_t>(view.length()) };
}
#else
inline std::string to_string(cstring_span<> view)
{
return{ view.data(), view.length() };
}
inline std::string to_string(string_span<> view)
{
return{ view.data(), view.length() };
}
inline std::wstring to_string(cwstring_span<> view)
{
return{ view.data(), view.length() };
}
inline std::wstring to_string(wstring_span<> view)
{
return{ view.data(), view.length() };
}
#endif
template<class CharT, size_t Extent = dynamic_range>
class basic_zstring_builder
{
public:
using string_span_type = basic_string_span<CharT, Extent>;
using value_type = CharT;
using pointer = CharT*;
using size_type = typename string_span_type::size_type;
using iterator = typename string_span_type::iterator;
basic_zstring_builder(CharT* data, size_type length) : sv_(data, length) {}
template<size_t Size>
basic_zstring_builder(CharT(&arr)[Size]) : sv_(arr) {}
pointer data() const { return sv_.data(); }
string_span_type view() const { return sv_; }
size_type length() const { return sv_.length(); }
pointer assume0() const { return data(); }
string_span_type ensure_z() const { return gsl::ensure_z(sv_); }
iterator begin() const { return sv_.begin(); }
iterator end() const { return sv_.end(); }
private:
string_span_type sv_;
};
template <size_t Max = dynamic_range>
using zstring_builder = basic_zstring_builder<char, Max>;
template <size_t Max = dynamic_range>
using wzstring_builder = basic_zstring_builder<wchar_t, Max>;
}
// VS 2013 workarounds
#ifdef _MSC_VER
#if _MSC_VER <= 1800
#pragma pop_macro("GSL_MSVC_HAS_TYPE_DEDUCTION_BUG")
#undef GSL_MSVC_HAS_TYPE_DEDUCTION_BUG
#endif // _MSC_VER <= 1800
#endif // _MSC_VER
#endif // GSL_STRING_SPAN_H

183
include/string_view.h
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@ -1,183 +0,0 @@
///////////////////////////////////////////////////////////////////////////////
//
// 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.
//
///////////////////////////////////////////////////////////////////////////////
#pragma once
#ifndef GSL_STRING_VIEW_H
#define GSL_STRING_VIEW_H
#include "array_view.h"
#include <cstring>
namespace gsl
{
//
// czstring and wzstring
//
// These are "tag" typedef's for C-style strings (i.e. null-terminated character arrays)
// that allow static analysis to help find bugs.
//
// There are no additional features/semantics that we can find a way to add inside the
// type system for these types that will not either incur significant runtime costs or
// (sometimes needlessly) break existing programs when introduced.
//
template<size_t Max = dynamic_range>
using czstring = const char*;
template<size_t Max = dynamic_range>
using cwzstring = const wchar_t*;
template<size_t Max = dynamic_range>
using zstring = char*;
template<size_t Max = dynamic_range>
using wzstring = wchar_t*;
//
// string_view and relatives
//
// Note that Extent is always single-dimension only
// Note that SizeType is defaulted to be smaller than size_t which is the array_view default
//
// TODO (neilmac) once array_view regains configurable size_type, update these typedef's
//
template <class CharT, size_t Extent = dynamic_range>
using basic_string_view = array_view<CharT, Extent>;
template<size_t Extent = dynamic_range>
using string_view = basic_string_view<char, Extent>;
template<size_t Extent = dynamic_range>
using cstring_view = basic_string_view<const char, Extent>;
template<size_t Extent = dynamic_range>
using wstring_view = basic_string_view<wchar_t, Extent>;
template<size_t Extent = dynamic_range>
using cwstring_view = basic_string_view<const wchar_t, Extent>;
//
// ensure_sentinel()
//
// Provides a way to obtain an array_view from a contiguous sequence
// that ends with a (non-inclusive) sentinel value.
//
// Will fail-fast if sentinel cannot be found before max elements are examined.
//
template<class T, class SizeType, const T Sentinel>
array_view<T, dynamic_range> ensure_sentinel(const T* seq, SizeType max = std::numeric_limits<SizeType>::max())
{
auto cur = seq;
while ((cur - seq) < max && *cur != Sentinel) ++cur;
fail_fast_assert(*cur == Sentinel);
return{ seq, cur - seq };
}
//
// ensure_z - creates a string_view for a czstring or cwzstring.
// Will fail fast if a null-terminator cannot be found before
// the limit of size_type.
//
template<class T>
inline basic_string_view<T, dynamic_range> ensure_z(T* const & sz, size_t max = std::numeric_limits<size_t>::max())
{
return ensure_sentinel<0>(sz, max);
}
// TODO (neilmac) there is probably a better template-magic way to get the const and non-const overloads to share an implementation
inline basic_string_view<char, dynamic_range> ensure_z(char* const & sz, size_t max)
{
auto len = strnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, len };
}
inline basic_string_view<const char, dynamic_range> ensure_z(const char* const& sz, size_t max)
{
auto len = strnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, len };
}
inline basic_string_view<wchar_t, dynamic_range> ensure_z(wchar_t* const & sz, size_t max)
{
auto len = wcsnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, len };
}
inline basic_string_view<const wchar_t, dynamic_range> ensure_z(const wchar_t* const & sz, size_t max)
{
auto len = wcsnlen(sz, max);
fail_fast_assert(sz[len] == 0); return{ sz, len };
}
template<class T, size_t N>
basic_string_view<T, dynamic_range> ensure_z(T(&sz)[N]) { return ensure_z(&sz[0], N); }
template<class Cont>
basic_string_view<typename std::remove_pointer<typename Cont::pointer>::type, dynamic_range> ensure_z(Cont& cont)
{
return ensure_z(cont.data(), cont.length());
}
//
// to_string() allow (explicit) conversions from string_view to string
//
template<class CharT, size_t Extent>
std::basic_string<typename std::remove_const<CharT>::type> to_string(basic_string_view<CharT, Extent> view)
{
return{ view.data(), view.length() };
}
template<class CharT, size_t Extent = dynamic_range>
class basic_zstring_builder
{
public:
using string_view_type = basic_string_view<CharT, Extent>;
using value_type = CharT;
using pointer = CharT*;
using size_type = typename string_view_type::size_type;
using iterator = typename string_view_type::iterator;
basic_zstring_builder(CharT* data, size_type length) : sv_(data, length) {}
template<size_t Size>
basic_zstring_builder(CharT(&arr)[Size]) : sv_(arr) {}
pointer data() const { return sv_.data(); }
string_view_type view() const { return sv_; }
size_type length() const { return sv_.length(); }
pointer assume0() const { return data(); }
string_view_type ensure_z() const { return gsl::ensure_z(sv_); }
iterator begin() const { return sv_.begin(); }
iterator end() const { return sv_.end(); }
private:
string_view_type sv_;
};
template <size_t Max = dynamic_range>
using zstring_builder = basic_zstring_builder<char, Max>;
template <size_t Max = dynamic_range>
using wzstring_builder = basic_zstring_builder<wchar_t, Max>;
}
#endif // GSL_STRING_VIEW_H

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tests/CMakeLists.txt
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@ -14,14 +14,15 @@ add_definitions(-DGSL_THROWS_FOR_TESTING)
if(MSVC14 OR MSVC12) # has the support we need
# remove unnecessary warnings about unchecked iterators
add_definitions(-D_SCL_SECURE_NO_WARNINGS)
add_compile_options(/W4)
else()
include(CheckCXXCompilerFlag)
CHECK_CXX_COMPILER_FLAG("-std=c++14" COMPILER_SUPPORTS_CXX14)
CHECK_CXX_COMPILER_FLAG("-std=c++11" COMPILER_SUPPORTS_CXX11)
if(COMPILER_SUPPORTS_CXX14)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++14 -Wall -Wno-missing-braces")
elseif(COMPILER_SUPPORTS_CXX11)
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11 -Wall -Wno-missing-braces")
else()
message(STATUS "The compiler ${CMAKE_CXX_COMPILER} has no C++11 support. Please use a different C++ compiler.")
endif()
@ -43,8 +44,8 @@ function(add_gsl_test name)
)
endfunction()
add_gsl_test(array_view_tests)
add_gsl_test(string_view_tests)
add_gsl_test(span_tests)
add_gsl_test(string_span_tests)
add_gsl_test(at_tests)
add_gsl_test(bounds_tests)
add_gsl_test(notnull_tests)

44
tests/bounds_tests.cpp
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@ -15,7 +15,7 @@
///////////////////////////////////////////////////////////////////////////////
#include <UnitTest++/UnitTest++.h>
#include <array_view.h>
#include <span.h>
#include <vector>
using namespace std;
@ -23,16 +23,18 @@ using namespace gsl;;
namespace
{
void use(unsigned int&) {}
void use(std::ptrdiff_t&) {}
}
SUITE(bounds_test)
{
TEST(basic_bounds)
{
for (auto point : static_bounds <unsigned int, dynamic_range, 3, 4 > { 2 })
for (auto point : static_bounds<dynamic_range, 3, 4 > { 2 })
{
for (unsigned int j = 0; j < decltype(point)::rank; j++)
for (decltype(point)::size_type j = 0;
j < static_cast<decltype(point)::size_type>(decltype(point)::rank);
j++)
{
use(j);
use(point[j]);
@ -42,20 +44,21 @@ SUITE(bounds_test)
TEST(bounds_basic)
{
static_bounds<size_t, 3, 4, 5> b;
static_bounds<3, 4, 5> b;
auto a = b.slice();
static_bounds<size_t, 4, dynamic_range, 2> x{ 4 };
(void)a;
static_bounds<4, dynamic_range, 2> x{ 4 };
x.slice().slice();
}
TEST (arrayview_iterator)
{
static_bounds<size_t, 4, dynamic_range, 2> bounds{ 3 };
static_bounds<4, dynamic_range, 2> bounds{ 3 };
auto itr = bounds.begin();
(void)itr;
#ifdef CONFIRM_COMPILATION_ERRORS
array_view< int, 4, dynamic_range, 2> av(nullptr, bounds);
span<int, 4, dynamic_range, 2> av(nullptr, bounds);
auto itr2 = av.cbegin();
@ -68,24 +71,25 @@ SUITE(bounds_test)
TEST (bounds_convertible)
{
static_bounds<size_t, 7, 4, 2> b1;
static_bounds<size_t, 7, dynamic_range, 2> b2 = b1;
static_bounds<7, 4, 2> b1;
static_bounds<7, dynamic_range, 2> b2 = b1;
(void)b2;
#ifdef CONFIRM_COMPILATION_ERRORS
static_bounds<size_t, 7, dynamic_range, 1> b4 = b2;
static_bounds<7, dynamic_range, 1> b4 = b2;
#endif
static_bounds<size_t, dynamic_range, dynamic_range, dynamic_range> b3 = b1;
static_bounds<int, 7, 4, 2> b4 = b3;
static_bounds<dynamic_range, dynamic_range, dynamic_range> b3 = b1;
static_bounds<7, 4, 2> b4 = b3;
(void)b4;
static_bounds<size_t, dynamic_range> b11;
static_bounds<dynamic_range> b11;
static_bounds<size_t, dynamic_range> b5;
static_bounds<size_t, 34> b6;
static_bounds<dynamic_range> b5;
static_bounds<34> b6;
b5 = static_bounds<size_t, 20>();
b5 = static_bounds<20>();
CHECK_THROW(b6 = b5, fail_fast);
b5 = static_bounds<size_t, 34>();
b5 = static_bounds<34>();
b6 = b5;
CHECK(b5 == b6);

1
tests/notnull_tests.cpp
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@ -69,6 +69,7 @@ SUITE(NotNullTests)
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

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tests/array_view_tests.cpp → tests/span_tests.cpp
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56
tests/string_view_tests.cpp → tests/string_span_tests.cpp
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@ -15,39 +15,40 @@
///////////////////////////////////////////////////////////////////////////////
#include <UnitTest++/UnitTest++.h>
#include <string_view.h>
#include <string_span.h>
#include <vector>
#include <cstdlib>
using namespace std;
using namespace gsl;
SUITE(string_view_tests)
SUITE(string_span_tests)
{
TEST(TestLiteralConstruction)
{
cwstring_view<> v = ensure_z(L"Hello");
cwstring_span<> v = ensure_z(L"Hello");
CHECK(5 == v.length());
#ifdef CONFIRM_COMPILATION_ERRORS
wstring_view<> v2 = ensure0(L"Hello");
wstring_span<> v2 = ensure0(L"Hello");
#endif
}
TEST(TestConstructFromStdString)
{
std::string s = "Hello there world";
cstring_view<> v = s;
CHECK(v.length() == s.length());
cstring_span<> v = s;
CHECK(v.length() == static_cast<cstring_span<>::size_type>(s.length()));
}
TEST(TestConstructFromStdVector)
{
std::vector<char> vec(5, 'h');
string_view<> v = vec;
CHECK(v.length() == vec.size());
string_span<> v = vec;
CHECK(v.length() == static_cast<string_span<>::size_type>(vec.size()));
}
TEST(TestStackArrayConstruction)
@ -55,47 +56,68 @@ SUITE(string_view_tests)
wchar_t stack_string[] = L"Hello";
{
cwstring_view<> v = ensure_z(stack_string);
cwstring_span<> v = ensure_z(stack_string);
CHECK(v.length() == 5);
CHECK(v.used_length() == v.length());
}
{
cwstring_view<> v = stack_string;
cwstring_span<> v = stack_string;
CHECK(v.length() == 6);
CHECK(v.used_length() == v.length());
}
{
wstring_view<> v = ensure_z(stack_string);
wstring_span<> v = ensure_z(stack_string);
CHECK(v.length() == 5);
CHECK(v.used_length() == v.length());
}
{
wstring_view<> v = stack_string;
wstring_span<> v = stack_string;
CHECK(v.length() == 6);
CHECK(v.used_length() == v.length());
}
}
TEST(TestConstructFromConstCharPointer)
{
const char* s = "Hello";
cstring_span<> v = ensure_z(s);
CHECK(v.length() == 5);
CHECK(v.used_length() == v.length());
}
TEST(TestConversionToConst)
{
char stack_string[] = "Hello";
string_view<> v = ensure_z(stack_string);
cstring_view<> v2 = v;
string_span<> v = ensure_z(stack_string);
cstring_span<> v2 = v;
CHECK(v.length() == v2.length());
}
TEST(TestConversionFromConst)
{
char stack_string[] = "Hello";
cstring_view<> v = ensure_z(stack_string);
cstring_span<> v = ensure_z(stack_string);
(void)v;
#ifdef CONFIRM_COMPILATION_ERRORS
string_view<> v2 = v;
string_view<> v3 = "Hello";
string_span<> v2 = v;
string_span<> v3 = "Hello";
#endif
}
TEST(TestToString)
{
auto s = gsl::to_string(cstring_span<>{});
CHECK(s.length() == 0);
char stack_string[] = "Hello";
cstring_span<> v = ensure_z(stack_string);
auto s2 = gsl::to_string(v);
CHECK(static_cast<cstring_span<>::size_type>(s2.length()) == v.length());
CHECK(s2.length() == 5);
}
}
int main(int, const char *[])