commit 15cd83a3cbec97511f3589493f478ec1a5a9a841
author Martin Storsjö <martin@martin.st> Mon Nov 09 11:45:13 2020 +0200
committer Copybara-Service <copybara-worker@google.com> Fri Feb 19 11:55:30 2021 -0800
tree 19ead0317eee36bed4bea827f3b8a3d6a6d17834
parent 9bc3910e8964bb1ea9843b00ff6cb90b82683dc1

[libcxx] Make generic_*string return paths with forward slashes on windows

This matches what MS STL returns; in std::filesystem, forward slashes
are considered generic dir separators that are valid on all platforms.

Differential Revision: https://reviews.llvm.org/D91181

GitOrigin-RevId: f4f5fb915104887fefa602cfcbd1d4fc8447d46b

include/filesystem

diff --git a/include/filesystem b/include/filesystem
index d333d02..2da24d4 100644
--- a/include/filesystem
+++ b/include/filesystem
@@ -1193,7 +1193,12 @@
 #if defined(_LIBCPP_WIN32API)
   _LIBCPP_INLINE_VISIBILITY _VSTD::wstring wstring() const { return __pn_; }
 
-  _VSTD::wstring generic_wstring() const { return __pn_; }
+  _VSTD::wstring generic_wstring() const {
+    _VSTD::wstring __s;
+    __s.resize(__pn_.size());
+    _VSTD::replace_copy(__pn_.begin(), __pn_.end(), __s.begin(), '\\', '/');
+    return __s;
+  }
 
 #if !defined(_LIBCPP_HAS_NO_LOCALIZATION)
   template <class _ECharT, class _Traits = char_traits<_ECharT>,
@@ -1230,13 +1235,24 @@
             class _Allocator = allocator<_ECharT> >
   basic_string<_ECharT, _Traits, _Allocator>
   generic_string(const _Allocator& __a = _Allocator()) const {
-    return string<_ECharT, _Traits, _Allocator>(__a);
+    using _Str = basic_string<_ECharT, _Traits, _Allocator>;
+    _Str __s = string<_ECharT, _Traits, _Allocator>(__a);
+    // Note: This (and generic_u8string below) is slightly suboptimal as
+    // it iterates twice over the string; once to convert it to the right
+    // character type, and once to replace path delimiters.
+    _VSTD::replace(__s.begin(), __s.end(),
+                   static_cast<_ECharT>('\\'), static_cast<_ECharT>('/'));
+    return __s;
   }
 
   _VSTD::string generic_string() const { return generic_string<char>(); }
   _VSTD::u16string generic_u16string() const { return generic_string<char16_t>(); }
   _VSTD::u32string generic_u32string() const { return generic_string<char32_t>(); }
-  __u8_string generic_u8string() const { return u8string(); }
+  __u8_string generic_u8string() const {
+    __u8_string __s = u8string();
+    _VSTD::replace(__s.begin(), __s.end(), '\\', '/');
+    return __s;
+  }
 #endif /* !_LIBCPP_HAS_NO_LOCALIZATION */
 #else /* _LIBCPP_WIN32API */
 

test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp

diff --git a/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
index 58c07e2..d899159 100644
--- a/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
@@ -32,17 +32,24 @@
 #include "min_allocator.h"
 #include "filesystem_test_helper.h"
 
-MultiStringType longString = MKSTR("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ/123456789/abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ");
+MultiStringType input = MKSTR("c:\\foo\\bar");
+#ifdef _WIN32
+// On windows, the generic_* accessors return a path with forward slashes
+MultiStringType ref = MKSTR("c:/foo/bar");
+#else
+// On posix, the input string is returned as-is
+MultiStringType ref = MKSTR("c:\\foo\\bar");
+#endif
 
 int main(int, char**)
 {
   using namespace fs;
-  auto const& MS = longString;
-  const char* value = longString;
+  auto const& MS = ref;
+  const char* value = input;
   const path p(value);
   {
     std::string s = p.generic_string();
-    assert(s == value);
+    assert(s == (const char*)MS);
   }
   {
 #if TEST_STD_VER > 17 && defined(__cpp_char8_t)