Add as_bytes for basic_string_span, fixes issue #655 (#683)

This commit is contained in:
beinhaerter 2018-05-29 04:03:10 +02:00 committed by Anna Gringauze
parent 51ae678d08
commit 75ad0c1b40
2 changed files with 34 additions and 0 deletions

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@ -376,6 +376,21 @@ std::basic_string<CharT, Traits, Allocator> to_basic_string(basic_string_span<gC
return {view.data(), static_cast<std::size_t>(view.length())}; return {view.data(), static_cast<std::size_t>(view.length())};
} }
template <class ElementType, std::ptrdiff_t Extent>
basic_string_span<const byte, details::calculate_byte_size<ElementType, Extent>::value>
as_bytes(basic_string_span<ElementType, Extent> s) noexcept
{
return { reinterpret_cast<const byte*>(s.data()), s.size_bytes() };
}
template <class ElementType, std::ptrdiff_t Extent,
class = std::enable_if_t<!std::is_const<ElementType>::value>>
basic_string_span<byte, details::calculate_byte_size<ElementType, Extent>::value>
as_writeable_bytes(basic_string_span<ElementType, Extent> s) noexcept
{
return {reinterpret_cast<byte*>(s.data()), s.size_bytes()};
}
// zero-terminated string span, used to convert // zero-terminated string span, used to convert
// zero-terminated spans to legacy strings // zero-terminated spans to legacy strings
template <typename CharT, std::ptrdiff_t Extent = dynamic_extent> template <typename CharT, std::ptrdiff_t Extent = dynamic_extent>

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@ -1167,3 +1167,22 @@ TEST_CASE("char32_t type")
CHECK(ss8 <= ss9); CHECK(ss8 <= ss9);
CHECK(ss8 != ss9); CHECK(ss8 != ss9);
} }
TEST_CASE("as_bytes")
{
cwzstring_span<> v(L"qwerty");
const auto s = v.as_string_span();
const auto bs = as_bytes(s);
CHECK(static_cast<const void*>(bs.data()) == static_cast<const void*>(s.data()));
CHECK(bs.size() == s.size_bytes());
}
TEST_CASE("as_writeable_bytes")
{
wchar_t buf[]{L"qwerty"};
wzstring_span<> v(buf);
const auto s = v.as_string_span();
const auto bs = as_writeable_bytes(s);
CHECK(static_cast<const void*>(bs.data()) == static_cast<const void*>(s.data()));
CHECK(bs.size() == s.size_bytes());
}