Replaced `fs::u8path` long-path support on windows by enabling it explicitly.

libmamba/CMakeLists.txt

@@ -120,6 +120,7 @@ foreach(script ${SHELL_SCRIPTS})
 endforeach()
 
 set(LIBMAMBA_SOURCES
+    longpath.manifest
     ${LIBMAMBA_SOURCE_DIR}/version.cpp
     # Core API (low-level)
     ${LIBMAMBA_SOURCE_DIR}/core/singletons.cpp

libmamba/include/mamba/core/mamba_fs.hpp

@@ -101,66 +101,56 @@ namespace fs
         u8path(const std::filesystem::path& path)
             : m_path(path)
         {
-            check_long_path();
         }
 
         u8path& operator=(const std::filesystem::path& path)
         {
             m_path = path;
-            check_long_path();
             return *this;
         }
 
         u8path& operator=(std::filesystem::path&& path)
         {
             m_path = std::move(path);
-            check_long_path();
             return *this;
         }
 
         u8path(std::string_view u8string)
             : m_path(from_utf8(u8string))
         {
-            check_long_path();
         }
 
         u8path& operator=(std::string_view u8string)
         {
             m_path = from_utf8(u8string);
-            check_long_path();
             return *this;
         }
 
         u8path(const char* u8string)
             : m_path(from_utf8(u8string))
         {
-            check_long_path();
         }
 
         u8path& operator=(const char* u8string)
         {
             m_path = from_utf8(u8string);
-            check_long_path();
             return *this;
         }
 
         u8path(const std::string& u8string)
             : m_path(from_utf8(u8string))
         {
-            check_long_path();
         }
 
         u8path& operator=(const std::string& u8string)
         {
             m_path = from_utf8(u8string);
-            check_long_path();
             return *this;
         }
 
         u8path& operator=(std::string&& u8string)
         {
             m_path = from_utf8(std::move(u8string));
-            check_long_path();
             return *this;
         }
 
@@ -169,33 +159,28 @@ namespace fs
         u8path(const wchar_t* wstr)
             : m_path(wstr)
         {
-            check_long_path();
         }
 
         u8path& operator=(const wchar_t* wstr)
         {
             m_path = wstr;
-            check_long_path();
             return *this;
         }
 
         u8path(const std::wstring& wstr)
             : m_path(wstr)
         {
-            check_long_path();
         }
 
         u8path& operator=(const std::wstring& wstr)
         {
             m_path = wstr;
-            check_long_path();
             return *this;
         }
 
         u8path& operator=(std::wstring&& wstr)
         {
             m_path = std::move(wstr);
-            check_long_path();
             return *this;
         }
 
@@ -241,81 +226,70 @@ namespace fs
             return m_path / wstr;
         }
 
-        template<typename T>
+        template <typename T>
         u8path& operator/=(T&& some_string)
         {
             *this = *this / std::forward<T>(some_string);
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(const u8path& to_append)
         {
             m_path += to_append.m_path;
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(const std::filesystem::path& to_append)
         {
             m_path += to_append;
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(std::string_view to_append)
         {
             m_path = from_utf8(this->string() + std::string(to_append));
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(std::wstring_view to_append)
         {
             m_path += to_append;
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(const char* to_append)
         {
             m_path = from_utf8(this->string() + to_append);
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(const wchar_t* to_append)
         {
             m_path += to_append;
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(const std::string& to_append)
         {
             m_path = from_utf8(this->string() + to_append);
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(const std::wstring& to_append)
         {
             m_path += to_append;
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(char to_append)
         {
             m_path = from_utf8(this->string() + to_append);
-            check_long_path();
             return *this;
         }
 
         u8path& operator+=(wchar_t to_append)
         {
             m_path += to_append;
-            check_long_path();
             return *this;
         }
 
@@ -411,14 +385,12 @@ namespace fs
         u8path& replace_filename(const u8path replacement)
         {
             m_path.replace_filename(replacement.m_path);
-            check_long_path();
             return *this;
         }
 
         u8path& replace_extension(const u8path replacement = u8path())
         {
             m_path.replace_extension(replacement.m_path);
-            check_long_path();
             return *this;
         }
 
@@ -541,7 +513,7 @@ namespace fs
         {
             return m_path.is_relative();
         }
-        
+
         bool has_root_path() const
         {
             return m_path.has_root_path();
@@ -602,7 +574,6 @@ namespace fs
             std::string raw_input;
             in >> std::quoted(raw_input);
             path.m_path = from_utf8(raw_input);
-            path.check_long_path();
             return in;
         }
 
@@ -618,20 +589,6 @@ namespace fs
 
     private:
         std::filesystem::path m_path;
-
-        void check_long_path()
-        {
-#if defined(_WIN32)
-            // When we have long paths on windows, we need to mark the path so that if the system is set to allow long paths, we handle them properly.
-            // To achieve this we need to prefix long paths with a marker. This is one of windows weirderies.
-            if (is_absolute()
-                && m_path.native().size() >= 248 // MAX_PATH - 12 (but MAX_PATH is not necessarilly available here - it's set to 260)
-                && !m_path.native()._Starts_with(LR"(\\?\)")) // TODO: replace by std::basic_string::starts_with() in C++20
-            {
-                m_path = LR"(\\?\)" + m_path.native();
-            }
-#endif
-        }
     };
 
     class directory_entry : public std::filesystem::directory_entry

libmamba/longpath.manifest

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3" >
+<application xmlns="urn:schemas-microsoft-com:asm.v3">
+    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
+        <ws2:longPathAware>true</ws2:longPathAware>
+    </windowsSettings>
+</application>
+</assembly>

libmamba/tests/CMakeLists.txt

@@ -6,6 +6,7 @@ find_package(Threads REQUIRED)
 include_directories(${GTEST_INCLUDE_DIRS} SYSTEM)
 
 set(TEST_SRCS
+    ../longpath.manifest
     test_activation.cpp
     test_channel.cpp
     test_configuration.cpp

libmamba/tests/test_filesystem.cpp

@@ -78,14 +78,11 @@ namespace mamba
     TEST(u8path, long_paths)
     {
         const auto tmp_dir = fs::temp_directory_path() / "mamba_fs_long_path";
-        EXPECT_FALSE(starts_with(tmp_dir.string(), u8R"(\\?\)"));
 
         fs::u8path long_path = tmp_dir;
         for (int i = 0; i < 42; ++i)
             long_path /= u8"some_very_long_prefix";
-#if defined(_WIN32)
-        EXPECT_TRUE(starts_with(long_path.string(), u8R"(\\?\)"));
-#endif
+
         fs::create_directories(long_path);
     }
 

libmambapy/CMakeLists.txt

@@ -19,6 +19,7 @@ endif ()
 
 pybind11_add_module(bindings
     src/main.cpp
+    longpath.manifest
 )
 target_link_libraries(bindings PUBLIC pybind11::pybind11 libmamba)
 set_property(TARGET bindings PROPERTY CXX_STANDARD 17)

libmambapy/longpath.manifest

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3" >
+<application xmlns="urn:schemas-microsoft-com:asm.v3">
+    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
+        <ws2:longPathAware>true</ws2:longPathAware>
+    </windowsSettings>
+</application>
+</assembly>

micromamba/CMakeLists.txt

@@ -21,6 +21,7 @@ set(MICROMAMBA_LINKAGE "DYNAMIC" CACHE STRING "micromamba linkage against librar
 # ============
 
 set(MICROMAMBA_SRCS
+    longpath.manifest
     ${CMAKE_CURRENT_SOURCE_DIR}/src/activate.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/clean.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/config.cpp

micromamba/longpath.manifest

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8" standalone="yes"?>
+<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0" xmlns:asmv3="urn:schemas-microsoft-com:asm.v3" >
+<application xmlns="urn:schemas-microsoft-com:asm.v3">
+    <windowsSettings xmlns:ws2="http://schemas.microsoft.com/SMI/2016/WindowsSettings">
+        <ws2:longPathAware>true</ws2:longPathAware>
+    </windowsSettings>
+</application>
+</assembly>