Merge branch 'develop'

.github/workflows/ci.yml

@@ -60,7 +60,7 @@ jobs:
           - { name: GCC w/ sanitizers, sanitize: yes,
               compiler: gcc-12,    cxxstd: '03,11,14,17,20', os: ubuntu-22.04 }
           - { name: Collect coverage, coverage: yes,
-              compiler: gcc-8,     cxxstd: '03,11',          os: ubuntu-20.04, install: 'g++-8-multilib', address-model: '32,64' }
+              compiler: gcc-8,     cxxstd: '03,11,14,17,2a', os: ubuntu-20.04, install: 'g++-8-multilib', address-model: '32,64' }
 
           # Linux, clang
           - { compiler: clang-3.5, cxxstd: '03,11',          os: ubuntu-20.04, container: 'ubuntu:16.04' }

doc/changelog.dox

@@ -1,5 +1,5 @@
 //
-// Copyright (c) 2019-2021 Alexander Grund
+// Copyright (c) 2019-2023 Alexander Grund
 //
 // Distributed under the Boost Software License, Version 1.0.
 // https://www.boost.org/LICENSE_1_0.txt
@@ -8,14 +8,18 @@
 
 \section changelog Changelog
 
-\subsection changelog_11_2_0 Nowide 11.2.0
+\subsection changelog_11_2_1 Nowide 11.2.1 (Boost 1.82)
+- Add `convert_string` overload accepting a string
+- Add `quoted` to output (quoted) paths (std::filesystem or boost::filesystem)
+
+\subsection changelog_11_2_0 Nowide 11.2.0 (Boost 1.80)
 - `filebuf`: Major performance improvement for Bulk I/O
 - `filebuf`: Fix wrong return value of `sync` when `fflush` failed
 - `filebuf`: Fix possible undefined behavior in a corner case when nothing was actually written but buffer is in "write" mode
 - `filebuf`: Limit putback of characters (i.e. `pbackfail`) only allowing putback of buffered characters (may be only 1 character)
 - Add missing define `NOWIDE_USE_WCHAR_OVERLOADS` (standalone only)
 
-\subsection changelog_11_1_4 Nowide 11.1.4
+\subsection changelog_11_1_4 Nowide 11.1.4 (Boost 1.79)
 - Fix possible redefinition of `_LARGEFILE_SOURCE`
 - Fix missing include when `BOOST_USE_WINDOWS_H` and `WIN32_LEAN_AND_MEAN` are defined.
 - Fix compile failures on recent MinGW-w64 compilers

doc/main.dox

@@ -303,6 +303,30 @@ However the `u8string()` member function can be used to obtain an UTF-8 encoded
 And to optain a `path` from an UTF-8 encoded string you may use `std::filesystem::u8path`
 or since C++20 one of the `path` constructors taking a `char8_t`-type input.
 
+To read/write `std::filesystem::path` instances from/to streams you'd usually use e.g. `os << path`.
+However that will effectively be run as `os << std::quoted(path.string())` which means a possible conversion
+to a narrow string which may not be UTF-8 encoded.
+For that \c quoted can be used:
+
+\code
+#include <boost/nowide/quoted.hpp>
+#include <filesystem>
+#include <sstream>
+
+std::string write(const std::filesystem::path& path)
+{
+    std::ostringstream s;
+    s << boost::nowide::quoted(path);
+    return s.str();
+}
+
+std::experimental::path read(std::istream& is)
+{
+    std::filesystem::path path;
+    is >> boost::nowide::quoted(path);
+    return path;
+}
+\endcode
 
 \section technical Technical Details
 \subsection technical_imple Windows vs POSIX

include/boost/nowide/quoted.hpp

@@ -0,0 +1,109 @@
+//
+// Copyright (c) 2023 Alexander Grund
+//
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#ifndef BOOST_NOWIDE_QUOTED_HPP_INCLUDED
+#define BOOST_NOWIDE_QUOTED_HPP_INCLUDED
+
+#include <boost/nowide/config.hpp>
+#include <boost/nowide/detail/is_path.hpp>
+#include <boost/nowide/utf/convert.hpp>
+#include <iomanip>
+#include <istream>
+#include <ostream>
+#include <type_traits>
+
+#if defined(__cpp_lib_quoted_string_io) && __cpp_lib_quoted_string_io >= 201304
+
+namespace boost {
+namespace nowide {
+    /// \cond INTERNAL
+    namespace detail {
+        template<class Path>
+        struct quoted;
+        template<typename T>
+        using remove_cvref_t = typename std::remove_cv<typename std::remove_reference<T>::type>::type;
+
+    } // namespace detail
+    /// \endcond
+
+    /// \brief Allows insertion and extraction of `filesystem::path` into/from streams.
+    ///
+    /// When used in an expression such as `out << quoted(path)`, where `out` is an output stream,
+    /// has the effect as-if `out << std::quoted(path.native())` was used.
+    ///
+    /// When used in an expression like `in >> quoted(path)`, where `in` is an input stream,
+    /// has the effect as-if `in >> std::quoted(path.native())` was used if that would be valid.
+    /// To that effect a temporary string is used, which on success is assigned to `path`.
+    ///
+    /// Will automatically convert between the streams `char_type` and `path::value_type` if neccessary.
+    template<class Path>
+#ifdef BOOST_NOWIDE_DOXYGEN
+    unspecified_type
+#else
+    detail::enable_if_path_t<detail::remove_cvref_t<Path>, detail::quoted<Path&>>
+#endif
+    quoted(Path& path)
+    {
+        return {path};
+    }
+
+    /// \cond INTERNAL
+    // Same but for const-refs and r-values
+    template<class Path>
+    detail::enable_if_path_t<detail::remove_cvref_t<Path>, detail::quoted<const Path&>> quoted(const Path& path)
+    {
+        return {path};
+    }
+
+    namespace detail {
+        template<typename CharOut,
+                 typename CharIn,
+                 typename = typename std::enable_if<!std::is_same<CharOut, CharIn>::value>::type>
+        std::basic_string<CharOut> maybe_convert_string(const std::basic_string<CharIn>& s)
+        {
+            return utf::convert_string<CharOut>(s);
+        }
+        template<typename Char>
+        const std::basic_string<Char>& maybe_convert_string(const std::basic_string<Char>& s)
+        {
+            return s;
+        }
+
+        template<typename T>
+        using requires_non_const =
+          typename std::enable_if<!std::is_const<typename std::remove_reference<T>::type>::value>::type;
+
+        template<class Path>
+        struct quoted
+        {
+            Path value;
+            template<typename CharType>
+            friend std::basic_ostream<CharType>& operator<<(std::basic_ostream<CharType>& out, const quoted& path)
+            {
+                return out << std::quoted(maybe_convert_string<CharType>(path.value.native()));
+            }
+
+            template<typename CharType, class Path2 = Path, typename = requires_non_const<Path2>>
+            friend std::basic_istream<CharType>& operator>>(std::basic_istream<CharType>& in, const quoted& path)
+            {
+                std::basic_string<CharType> value;
+                using PlainPath = remove_cvref_t<Path>;
+                if(in >> std::quoted(value))
+                    path.value = PlainPath(maybe_convert_string<typename PlainPath::value_type>(value));
+                return in;
+            }
+        };
+
+    } // namespace detail
+    /// \endcond
+} // namespace nowide
+} // namespace boost
+
+#elif defined(BOOST_PRAGMA_MESSAGE)
+BOOST_PRAGMA_MESSAGE("To use boost::nowide::quoted at least C++14 is required.")
+#endif
+
+#endif

include/boost/nowide/utf/convert.hpp

@@ -90,6 +90,17 @@ namespace nowide {
             return result;
         }
 
+        /// Convert the UTF sequence in the input string from \a CharIn to \a CharOut
+        /// and return it as a string
+        ///
+        /// Any illegal sequences are replaced with the replacement character, see #BOOST_NOWIDE_REPLACEMENT_CHARACTER
+        /// \tparam CharOut Output character type
+        template<typename CharOut, typename CharIn>
+        std::basic_string<CharOut> convert_string(const std::basic_string<CharIn>& s)
+        {
+            return convert_string<CharOut>(s.data(), s.data() + s.size());
+        }
+
     } // namespace utf
 } // namespace nowide
 } // namespace boost

test/test_fs.cpp

@@ -13,11 +13,97 @@
 #include <boost/nowide/convert.hpp>
 #include <boost/nowide/cstdio.hpp>
 #include <boost/nowide/fstream.hpp>
+#include <boost/nowide/quoted.hpp>
+#include <boost/nowide/utf/convert.hpp>
 #include "test.hpp"
+#include <iomanip>
+#include <sstream>
+#include <type_traits>
 #if defined(_MSC_VER)
 #pragma warning(disable : 4714) // function marked as __forceinline not inlined
 #endif
-#include <boost/filesystem/operations.hpp>
+#include <boost/filesystem.hpp>
+
+// Exclude apple as support there is target level specific -.-
+#if defined(__cpp_lib_filesystem) && !defined(__APPLE__)
+#include <filesystem>
+#define BOOST_NOWIDE_TEST_STD_PATH
+#endif
+#if defined(__cpp_lib_experimental_filesystem)
+#ifndef _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING
+#define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING
+#endif
+#include <experimental/filesystem>
+#define BOOST_NOWIDE_TEST_STD_EXPERIMENTAL_PATH
+#endif
+
+template<typename T, typename = void>
+struct is_istreamable : std::false_type
+{};
+using boost::nowide::detail::void_t;
+template<typename T>
+struct is_istreamable<T, void_t<decltype(std::declval<std::istream&>() >> std::declval<T>())>> : std::true_type
+{};
+
+template<typename T_Char>
+std::string maybe_narrow(const std::basic_string<T_Char>& s)
+{
+    return boost::nowide::narrow(s);
+}
+
+const std::string& maybe_narrow(const std::string& s)
+{
+    return s;
+}
+
+template<class Path>
+void test_fs_path_io(std::string utf8_name)
+{
+#if defined(__cpp_lib_quoted_string_io) && __cpp_lib_quoted_string_io >= 201304
+    Path path(boost::nowide::utf::convert_string<typename Path::value_type>(utf8_name));
+    // Get native and UTF-8/narrow name here as the Path ctor may change the string (e.g. slash substitution)
+    const auto nativeName = path.native();
+    utf8_name = maybe_narrow(nativeName);
+    // Output
+    std::ostringstream s, sRef;
+    sRef << std::quoted(utf8_name);
+    s << boost::nowide::quoted(path);
+    TEST_EQ(s.str(), sRef.str());
+    // const
+    const Path constPath(path);
+    s.str("");
+    s << boost::nowide::quoted(constPath);
+    TEST_EQ(s.str(), sRef.str());
+    // Rvalue
+    s.str("");
+    s << boost::nowide::quoted(Path(path));
+    TEST_EQ(s.str(), sRef.str());
+
+    // Input
+    std::istringstream sIn(sRef.str());
+    Path pathOut;
+    static_assert(is_istreamable<decltype(boost::nowide::quoted(pathOut))>::value, "!");
+    sIn >> boost::nowide::quoted(pathOut);
+    TEST_EQ(pathOut.native(), nativeName);
+    // Can't read into a const path
+    static_assert(!is_istreamable<decltype(boost::nowide::quoted(constPath))>::value, "!");
+    // or an Rvalue
+    static_assert(!is_istreamable<decltype(boost::nowide::quoted(Path(path)))>::value, "!");
+
+    // Wide stream
+    std::wostringstream ws, wsRef;
+    wsRef << std::quoted(boost::nowide::widen(utf8_name));
+    ws << boost::nowide::quoted(path);
+    TEST_EQ(ws.str(), wsRef.str());
+    std::wistringstream wsIn(wsRef.str());
+    pathOut.clear();
+    wsIn >> boost::nowide::quoted(pathOut);
+    TEST_EQ(maybe_narrow(pathOut.native()), utf8_name);
+#else
+    (void)utf8_name; // Suppress unused warning
+    std::cout << "Skipping tests for boost::nowide::quoted" << std::endl;
+#endif
+}
 
 // coverity[root_function]
 void test_main(int, char** argv, char**)
@@ -63,4 +149,15 @@ void test_main(int, char** argv, char**)
         TEST(test == "Test");
     }
     boost::filesystem::remove(path);
+
+    std::cout << "Testing boost::filesystem::path" << std::endl;
+    test_fs_path_io<boost::filesystem::path>(utf8_name);
+#ifdef BOOST_NOWIDE_TEST_STD_EXPERIMENTAL_PATH
+    std::cout << "Testing std::experimental::filesystem::path" << std::endl;
+    test_fs_path_io<std::experimental::filesystem::path>(utf8_name);
+#endif
+#ifdef BOOST_NOWIDE_TEST_STD_PATH
+    std::cout << "Testing std::filesystem::path" << std::endl;
+    test_fs_path_io<std::filesystem::path>(utf8_name);
+#endif
 }