Splitting out pybind11/stl/filesystem.h.

CMakeLists.txt

@@ -125,7 +125,8 @@ set(PYBIND11_HEADERS
     include/pybind11/pybind11.h
     include/pybind11/pytypes.h
     include/pybind11/stl.h
-    include/pybind11/stl_bind.h)
+    include/pybind11/stl_bind.h
+    include/pybind11/stl/filesystem.h)
 
 # Compare with grep and warn if mismatched
 if(PYBIND11_MASTER_PROJECT AND NOT CMAKE_VERSION VERSION_LESS 3.12)

include/pybind11/stl.h

@@ -41,21 +41,11 @@
 #    include <variant>
 #    define PYBIND11_HAS_VARIANT 1
 #  endif
-// std::filesystem::path
-#  if defined(PYBIND11_CPP17) && __has_include(<filesystem>) && \
-      PY_VERSION_HEX >= 0x03060000
-#    include <filesystem>
-#    define PYBIND11_HAS_FILESYSTEM 1
-#  endif
 #elif defined(_MSC_VER) && defined(PYBIND11_CPP17)
 #  include <optional>
 #  include <variant>
 #  define PYBIND11_HAS_OPTIONAL 1
 #  define PYBIND11_HAS_VARIANT 1
-#  if PY_VERSION_HEX >= 0x03060000
-#    include <filesystem>
-#    define PYBIND11_HAS_FILESYSTEM 1
-#  endif
 #endif
 
 PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
@@ -387,77 +377,6 @@ template <typename... Ts>
 struct type_caster<std::variant<Ts...>> : variant_caster<std::variant<Ts...>> { };
 #endif
 
-#if defined(PYBIND11_HAS_FILESYSTEM)
-template<typename T> struct path_caster {
-
-private:
-    static PyObject* unicode_from_fs_native(const std::string& w) {
-#if !defined(PYPY_VERSION)
-        return PyUnicode_DecodeFSDefaultAndSize(w.c_str(), ssize_t(w.size()));
-#else
-        // PyPy mistakenly declares the first parameter as non-const.
-        return PyUnicode_DecodeFSDefaultAndSize(
-            const_cast<char*>(w.c_str()), ssize_t(w.size()));
-#endif
-    }
-
-    static PyObject* unicode_from_fs_native(const std::wstring& w) {
-        return PyUnicode_FromWideChar(w.c_str(), ssize_t(w.size()));
-    }
-
-public:
-    static handle cast(const T& path, return_value_policy, handle) {
-        if (auto py_str = unicode_from_fs_native(path.native())) {
-            return module::import("pathlib").attr("Path")(reinterpret_steal<object>(py_str))
-                   .release();
-        }
-        return nullptr;
-    }
-
-    bool load(handle handle, bool) {
-        // PyUnicode_FSConverter and PyUnicode_FSDecoder normally take care of
-        // calling PyOS_FSPath themselves, but that's broken on PyPy (PyPy
-        // issue #3168) so we do it ourselves instead.
-        PyObject* buf = PyOS_FSPath(handle.ptr());
-        if (!buf) {
-            PyErr_Clear();
-            return false;
-        }
-        PyObject* native = nullptr;
-        if constexpr (std::is_same_v<typename T::value_type, char>) {
-            if (PyUnicode_FSConverter(buf, &native)) {
-                if (auto c_str = PyBytes_AsString(native)) {
-                    // AsString returns a pointer to the internal buffer, which
-                    // must not be free'd.
-                    value = c_str;
-                }
-            }
-        } else if constexpr (std::is_same_v<typename T::value_type, wchar_t>) {
-            if (PyUnicode_FSDecoder(buf, &native)) {
-                if (auto c_str = PyUnicode_AsWideCharString(native, nullptr)) {
-                    // AsWideCharString returns a new string that must be free'd.
-                    value = c_str;  // Copies the string.
-                    PyMem_Free(c_str);
-                }
-            }
-        }
-        Py_XDECREF(native);
-        Py_DECREF(buf);
-        if (PyErr_Occurred()) {
-            PyErr_Clear();
-            return false;
-        } else {
-            return true;
-        }
-    }
-
-    PYBIND11_TYPE_CASTER(T, _("os.PathLike"));
-};
-
-template<> struct type_caster<std::filesystem::path>
-    : public path_caster<std::filesystem::path> {};
-#endif
-
 PYBIND11_NAMESPACE_END(detail)
 
 inline std::ostream &operator<<(std::ostream &os, const handle &obj) {

include/pybind11/stl/filesystem.h

@@ -0,0 +1,92 @@
+// Copyright (c) 2021 The Pybind Development Team.
+// All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+#pragma once
+
+#include "../detail/common.h"
+
+#ifdef __has_include
+#  if defined(PYBIND11_CPP17) && __has_include(<filesystem>) && \
+      PY_VERSION_HEX >= 0x03060000
+#    include <filesystem>
+#    define PYBIND11_HAS_FILESYSTEM 1
+#  endif
+#endif
+
+PYBIND11_NAMESPACE_BEGIN(PYBIND11_NAMESPACE)
+PYBIND11_NAMESPACE_BEGIN(detail)
+
+#if defined(PYBIND11_HAS_FILESYSTEM)
+template<typename T> struct path_caster {
+
+private:
+    static PyObject* unicode_from_fs_native(const std::string& w) {
+#if !defined(PYPY_VERSION)
+        return PyUnicode_DecodeFSDefaultAndSize(w.c_str(), ssize_t(w.size()));
+#else
+        // PyPy mistakenly declares the first parameter as non-const.
+        return PyUnicode_DecodeFSDefaultAndSize(
+            const_cast<char*>(w.c_str()), ssize_t(w.size()));
+#endif
+    }
+
+    static PyObject* unicode_from_fs_native(const std::wstring& w) {
+        return PyUnicode_FromWideChar(w.c_str(), ssize_t(w.size()));
+    }
+
+public:
+    static handle cast(const T& path, return_value_policy, handle) {
+        if (auto py_str = unicode_from_fs_native(path.native())) {
+            return module::import("pathlib").attr("Path")(reinterpret_steal<object>(py_str))
+                   .release();
+        }
+        return nullptr;
+    }
+
+    bool load(handle handle, bool) {
+        // PyUnicode_FSConverter and PyUnicode_FSDecoder normally take care of
+        // calling PyOS_FSPath themselves, but that's broken on PyPy (PyPy
+        // issue #3168) so we do it ourselves instead.
+        PyObject* buf = PyOS_FSPath(handle.ptr());
+        if (!buf) {
+            PyErr_Clear();
+            return false;
+        }
+        PyObject* native = nullptr;
+        if constexpr (std::is_same_v<typename T::value_type, char>) {
+            if (PyUnicode_FSConverter(buf, &native)) {
+                if (auto c_str = PyBytes_AsString(native)) {
+                    // AsString returns a pointer to the internal buffer, which
+                    // must not be free'd.
+                    value = c_str;
+                }
+            }
+        } else if constexpr (std::is_same_v<typename T::value_type, wchar_t>) {
+            if (PyUnicode_FSDecoder(buf, &native)) {
+                if (auto c_str = PyUnicode_AsWideCharString(native, nullptr)) {
+                    // AsWideCharString returns a new string that must be free'd.
+                    value = c_str;  // Copies the string.
+                    PyMem_Free(c_str);
+                }
+            }
+        }
+        Py_XDECREF(native);
+        Py_DECREF(buf);
+        if (PyErr_Occurred()) {
+            PyErr_Clear();
+            return false;
+        } else {
+            return true;
+        }
+    }
+
+    PYBIND11_TYPE_CASTER(T, _("os.PathLike"));
+};
+
+template<> struct type_caster<std::filesystem::path>
+    : public path_caster<std::filesystem::path> {};
+#endif // PYBIND11_HAS_FILESYSTEM
+
+PYBIND11_NAMESPACE_END(detail)
+PYBIND11_NAMESPACE_END(PYBIND11_NAMESPACE)

tests/extra_python_package/test_files.py

@@ -34,6 +34,7 @@
     "include/pybind11/pytypes.h",
     "include/pybind11/stl.h",
     "include/pybind11/stl_bind.h",
+    "include/pybind11/stl/filesystem.h",
 }
 
 detail_headers = {

tests/test_stl.cpp

@@ -10,6 +10,7 @@
 #include "pybind11_tests.h"
 #include "constructor_stats.h"
 #include <pybind11/stl.h>
+#include <pybind11/stl/filesystem.h>
 
 #include <vector>
 #include <string>