Upgrade only MSVC to the real std::filesystem

setup.py

@@ -1,17 +1,45 @@
 #!/usr/bin/python3
 
 import os
-import platform
+from distutils.ccompiler import get_default_compiler
 from setuptools import setup
+from setuptools.command.build_ext import build_ext
 from setuptools.extension import Extension
 
 source_files = [os.path.join("src", x) for x in os.listdir("src") if x.lower().endswith(".cpp")]
 
-extra_compile_args = []
-extra_link_args = []
+# As of July 2026, setuptools doesn't seem to include its own method to add compiler flags dependent
+# on the specific compiler (I legitimately don't understand how extra_compile_args is supposed to
+# work normally). But it does provide distutils' interface for checking what the compiler is, which
+# should work in a stable way until they add their own way.
+# See https://setuptools.pypa.io/en/latest/userguide/interfaces.html for info on stability tiers.
+# See https://setuptools.pypa.io/en/latest/userguide/extension.html for the recommendation to
+# inherit from existing commands to augment build functionality.
+# See https://github.com/pypa/setuptools/issues/2806 for people asking for an upgrade path for many
+# things related to creating and detecting compilers.
+# Especially this comment: https://github.com/pypa/setuptools/issues/2806#issuecomment-1367674526
+class build_ext_with_compiler_flags(build_ext):
+    def finalize_options(self):
+        super().finalize_options()
 
-if platform.system() == "Linux" or platform.system() == "Darwin":
-    extra_compile_args = ["-std=c++11"]
+        extra_compile_args = []
+        extra_link_args = []
+
+        compiler_type = None
+        if self.compiler is None:
+            compiler_type = get_default_compiler()
+        else:
+            compiler_type = self.compiler
+
+        if compiler_type == 'msvc':
+            extra_compile_args.append('/std:c++17')
+            extra_compile_args.append('/D_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING')
+        else:
+            extra_compile_args.append('-std=c++11')
+
+        for ext in self.extensions:
+            ext.extra_compile_args.extend(extra_compile_args)
+            ext.extra_link_args.extend(extra_link_args)
 
 setup(name="ccscript",
     version="1.500",
@@ -20,8 +48,8 @@
     ext_modules=[
         Extension("ccscript",
                   source_files,
-                  language="c++",
-                  extra_compile_args=extra_compile_args,
-                  extra_link_args=extra_link_args
+                  language="c++"
                   )
-    ])
+    ],
+    cmdclass={'build_ext': build_ext_with_compiler_flags}
+    )

src/fs.h

@@ -1,10 +1,7 @@
 #pragma once
 #ifdef _WIN32
-	#ifndef _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING
-	#define _SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING
-	#endif // !_SILENCE_EXPERIMENTAL_FILESYSTEM_DEPRECATION_WARNING
-	#include <experimental/filesystem>
-	namespace fs = std::experimental::filesystem::v1;
+	#include <filesystem>
+	namespace fs = std::filesystem;
 #else
 	#include "filesystem/filesystem_mini.h"
 	namespace fs = filesystem;

vs2019/ccscript.vcxproj

@@ -60,9 +60,10 @@
     <ClCompile>
       <WarningLevel>Level3</WarningLevel>
       <SDLCheck>true</SDLCheck>
-      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <RuntimeLibrary>MultiThreadedDebug</RuntimeLibrary>
+      <LanguageStandard>stdcpp17</LanguageStandard>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
@@ -82,9 +83,10 @@
       <FunctionLevelLinking>true</FunctionLevelLinking>
       <IntrinsicFunctions>true</IntrinsicFunctions>
       <SDLCheck>true</SDLCheck>
-      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>WIN32;NDEBUG;_CONSOLE;_SILENCE_CXX17_CODECVT_HEADER_DEPRECATION_WARNING;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <ConformanceMode>true</ConformanceMode>
       <RuntimeLibrary>MultiThreaded</RuntimeLibrary>
+      <LanguageStandard>stdcpp17</LanguageStandard>
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>

vs2019/tests.vcxproj

@@ -77,6 +77,7 @@
       <PrecompiledHeader />
       <WarningLevel>Level3</WarningLevel>
       <DebugInformationFormat>ProgramDatabase</DebugInformationFormat>
+      <LanguageStandard>stdcpp17</LanguageStandard>
     </ClCompile>
     <Link>
       <GenerateDebugInformation>true</GenerateDebugInformation>