release/20.x: [libcxx] Provide locale conversions to tests through lit substitution (#105651)

.github/workflows/libcxx-build-and-test.yaml

@@ -197,10 +197,20 @@ jobs:
           os: macos-15
         - config: apple-configuration
           os: macos-15
+        # TODO: These jobs are intended to test back-deployment (building against ToT libc++ but running against an
+        #       older system-provided libc++.dylib). Doing this properly would require building the test suite on a
+        #       recent macOS using a recent Clang (hence recent Xcode), and then running the actual test suite on an
+        #       older mac. We could do that by e.g. sharing artifacts between the two jobs.
+        #
+        #       However, our Lit configuration currently doesn't provide a good way to do that in a batch, so our only
+        #       alternative is to actually build on the same host that we're going to run on. Sadly, that doesn't work
+        #       since older macOSes don't support newer Xcodes. For now, we run the "backdeployment" jobs on recent
+        #       macOS versions as a way to avoid rotting that configuration, but it doesn't provide a lot of additional
+        #       coverage.
         - config: apple-system
-          os: macos-13
+          os: macos-15
         - config: apple-system-hardened
-          os: macos-13
+          os: macos-15
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4

libcxx/test/libcxx/input.output/iostreams.base/ios.base/ios.base.cons/dtor.uninitialized.pass.cpp

@@ -6,11 +6,14 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // UNSUPPORTED: no-exceptions
 
 // The fix for issue 57964 requires an updated dylib due to explicit
 // instantiations. That means Apple backdeployment targets remain broken.
-// XFAIL: using-built-library-before-llvm-19
+// XFAIL using-built-library-before-llvm-19
 
 // <ios>
 

libcxx/test/libcxx/strings/basic.string/string.capacity/allocation_size.pass.cpp

@@ -8,11 +8,6 @@
 
 // <string>
 
-// This test demonstrates the smaller allocation sizes when the alignment
-// requirements of std::string are dropped from 16 to 8.
-//
-// XFAIL: using-built-library-before-llvm-19
-
 #include <algorithm>
 #include <cassert>
 #include <cstddef>

libcxx/test/std/input.output/file.streams/fstreams/filebuf.virtuals/setbuf.pass.cpp

@@ -6,12 +6,16 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // <fstream>
 
 // basic_streambuf<charT, traits>* setbuf(char_type* s, streamsize n) override;
 
-// In C++23 and later, this test requires support for P2467R1 in the dylib (a3f17ba3febbd546f2342ffc780ac93b694fdc8d)
-// XFAIL: (!c++03 && !c++11 && !c++14 && !c++17 && !c++20) && using-built-library-before-llvm-18
+// This test requires the fix to https://github.com/llvm/llvm-project/issues/60509 in the dylib,
+// which landed in 5afb937d8a30445642ccaf33866ee4cdd0713222.
+// XFAIL using-built-library-before-llvm-19
 
 #include <fstream>
 #include <cstddef>

libcxx/test/std/input.output/iostream.format/input.streams/istream.unformatted/sync.pass.cpp

@@ -6,14 +6,17 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // <istream>
 
 // int sync();
 
 // The fix for bug 51497 and bug 51499 require and updated dylib due to
 // explicit instantiations. That means Apple backdeployment targets remain
 // broken.
-// XFAIL: using-built-library-before-llvm-19
+// XFAIL using-built-library-before-llvm-19
 
 #include <istream>
 #include <cassert>

libcxx/test/std/localization/locale.categories/category.collate/locale.collate.byname/compare.pass.cpp

@@ -6,6 +6,9 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // Bionic has minimal locale support, investigate this later.
 // XFAIL: LIBCXX-ANDROID-FIXME
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_fr_FR.pass.cpp

@@ -6,13 +6,18 @@
 //
 //===----------------------------------------------------------------------===//
 
-// XFAIL: darwin
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
+// XFAIL darwin
 
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 
 // REQUIRES: locale.fr_FR.UTF-8
 
+// ADDITIONAL_COMPILE_FLAGS: -DFR_MON_THOU_SEP=%{LOCALE_CONV_FR_FR_UTF_8_MON_THOUSANDS_SEP}
+
 // <locale>
 
 // class money_get<charT, InputIterator>
@@ -59,7 +64,8 @@ class my_facetw
 };
 
 static std::wstring convert_thousands_sep(std::wstring const& in) {
-  return LocaleHelpers::convert_thousands_sep_fr_FR(in);
+  const wchar_t fr_sep = LocaleHelpers::mon_thousands_sep_or_default(FR_MON_THOU_SEP);
+  return LocaleHelpers::convert_thousands_sep(in, fr_sep);
 }
 #endif // TEST_HAS_NO_WIDE_CHARACTERS
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_ru_RU.pass.cpp

@@ -6,11 +6,16 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 
 // REQUIRES: locale.ru_RU.UTF-8
 
+// ADDITIONAL_COMPILE_FLAGS: -DRU_MON_THOU_SEP=%{LOCALE_CONV_RU_RU_UTF_8_MON_THOUSANDS_SEP}
+
 // XFAIL: glibc-old-ru_RU-decimal-point
 
 // <locale>
@@ -52,7 +57,8 @@ class my_facetw
 };
 
 static std::wstring convert_thousands_sep(std::wstring const& in) {
-  return LocaleHelpers::convert_thousands_sep_ru_RU(in);
+  const wchar_t ru_sep = LocaleHelpers::mon_thousands_sep_or_default(RU_MON_THOU_SEP);
+  return LocaleHelpers::convert_thousands_sep(in, ru_sep);
 }
 #endif // TEST_HAS_NO_WIDE_CHARACTERS
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.money.get/locale.money.get.members/get_long_double_zh_CN.pass.cpp

@@ -5,7 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_fr_FR.pass.cpp

@@ -6,13 +6,18 @@
 //
 //===----------------------------------------------------------------------===//
 
-// XFAIL: darwin
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
+// XFAIL darwin
 
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 
 // REQUIRES: locale.fr_FR.UTF-8
 
+// ADDITIONAL_COMPILE_FLAGS: -DFR_MON_THOU_SEP=%{LOCALE_CONV_FR_FR_UTF_8_MON_THOUSANDS_SEP}
+
 // <locale>
 
 // class money_put<charT, OutputIterator>
@@ -59,7 +64,8 @@ class my_facetw
 };
 
 static std::wstring convert_thousands_sep(std::wstring const& in) {
-  return LocaleHelpers::convert_thousands_sep_fr_FR(in);
+  const wchar_t fr_sep = LocaleHelpers::mon_thousands_sep_or_default(FR_MON_THOU_SEP);
+  return LocaleHelpers::convert_thousands_sep(in, fr_sep);
 }
 #endif // TEST_HAS_NO_WIDE_CHARACTERS
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_ru_RU.pass.cpp

@@ -6,11 +6,16 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 
 // REQUIRES: locale.ru_RU.UTF-8
 
+// ADDITIONAL_COMPILE_FLAGS: -DRU_MON_THOU_SEP=%{LOCALE_CONV_RU_RU_UTF_8_MON_THOUSANDS_SEP}
+
 // XFAIL: glibc-old-ru_RU-decimal-point
 
 // <locale>
@@ -52,7 +57,8 @@ class my_facetw
 };
 
 static std::wstring convert_thousands_sep(std::wstring const& in) {
-  return LocaleHelpers::convert_thousands_sep_ru_RU(in);
+  const wchar_t ru_sep = LocaleHelpers::mon_thousands_sep_or_default(RU_MON_THOU_SEP);
+  return LocaleHelpers::convert_thousands_sep(in, ru_sep);
 }
 #endif // TEST_HAS_NO_WIDE_CHARACTERS
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.money.put/locale.money.put.members/put_long_double_zh_CN.pass.cpp

@@ -5,7 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/curr_symbol.pass.cpp

@@ -5,7 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/grouping.pass.cpp

@@ -5,8 +5,11 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
-// XFAIL: darwin
+
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
+// XFAIL darwin
 //
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd

libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/neg_format.pass.cpp

@@ -5,7 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 

libcxx/test/std/localization/locale.categories/category.monetary/locale.moneypunct.byname/thousands_sep.pass.cpp

@@ -9,13 +9,14 @@
 // NetBSD does not support LC_MONETARY at the moment
 // XFAIL: netbsd
 
-// XFAIL: LIBCXX-FREEBSD-FIXME
-
 // REQUIRES: locale.en_US.UTF-8
 // REQUIRES: locale.fr_FR.UTF-8
 // REQUIRES: locale.ru_RU.UTF-8
 // REQUIRES: locale.zh_CN.UTF-8
 
+// ADDITIONAL_COMPILE_FLAGS: -DFR_MON_THOU_SEP=%{LOCALE_CONV_FR_FR_UTF_8_MON_THOUSANDS_SEP}
+// ADDITIONAL_COMPILE_FLAGS: -DRU_MON_THOU_SEP=%{LOCALE_CONV_RU_RU_UTF_8_MON_THOUSANDS_SEP}
+
 // <locale>
 
 // class moneypunct_byname<charT, International>
@@ -27,6 +28,7 @@
 #include <cassert>
 
 #include "test_macros.h"
+#include "locale_helpers.h"
 #include "platform_support.h" // locale name macros
 
 class Fnf
@@ -110,17 +112,10 @@ int main(int, char**)
         Fnt f(LOCALE_fr_FR_UTF_8, 1);
         assert(f.thousands_sep() == ' ');
     }
-    // The below tests work around GLIBC's use of U202F as mon_thousands_sep.
+
 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
-#if defined(_CS_GNU_LIBC_VERSION)
-    const wchar_t fr_sep = glibc_version_less_than("2.27") ? L' ' : L'\u202F';
-#elif defined(_WIN32)
-    const wchar_t fr_sep = L'\u00A0';
-#elif defined(_AIX)
-    const wchar_t fr_sep = L'\u202F';
-#else
-    const wchar_t fr_sep = L' ';
-#endif
+    const wchar_t fr_sep = LocaleHelpers::mon_thousands_sep_or_default(FR_MON_THOU_SEP);
+
     {
         Fwf f(LOCALE_fr_FR_UTF_8, 1);
         assert(f.thousands_sep() == fr_sep);
@@ -140,19 +135,8 @@ int main(int, char**)
         assert(f.thousands_sep() == sep);
     }
 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
-    // The below tests work around GLIBC's use of U00A0 as mon_thousands_sep
-    // and U002E as mon_decimal_point.
-    // TODO: Fix thousands_sep for 'char'.
-    // related to https://gcc.gnu.org/bugzilla/show_bug.cgi?id=16006
-#   if defined(_CS_GNU_LIBC_VERSION)
-    // FIXME libc++ specifically works around \u00A0 by translating it into
-    // a regular space.
-    const wchar_t wsep = glibc_version_less_than("2.27") ? L'\u00A0' : L'\u202F';
-#   elif defined(_WIN32) || defined(_AIX)
-    const wchar_t wsep = L'\u00A0';
-#   else
-    const wchar_t wsep = L' ';
-#   endif
+    const wchar_t wsep = LocaleHelpers::mon_thousands_sep_or_default(RU_MON_THOU_SEP);
+
     {
         Fwf f(LOCALE_ru_RU_UTF_8, 1);
         assert(f.thousands_sep() == wsep);

libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_double.pass.cpp

@@ -6,6 +6,13 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
+// The fix for LWG2381 (https://github.com/llvm/llvm-project/pull/77948) changed behavior of
+// FP parsing. This requires 3e15c97fa3812993bdc319827a5c6d867b765ae8 in the dylib.
+// XFAIL using-built-library-before-llvm-19
+
 // <locale>
 
 // class num_get<charT, InputIterator>

libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_float.pass.cpp

@@ -6,6 +6,13 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
+// The fix for LWG2381 (https://github.com/llvm/llvm-project/pull/77948) changed behavior of
+// FP parsing. This requires 3e15c97fa3812993bdc319827a5c6d867b765ae8 in the dylib.
+// XFAIL using-built-library-before-llvm-19
+
 // <locale>
 
 // class num_get<charT, InputIterator>

libcxx/test/std/localization/locale.categories/category.numeric/locale.num.get/facet.num.get.members/get_long_double.pass.cpp

@@ -6,6 +6,13 @@
 //
 //===----------------------------------------------------------------------===//
 
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
+// The fix for LWG2381 (https://github.com/llvm/llvm-project/pull/77948) changed behavior of
+// FP parsing. This requires 3e15c97fa3812993bdc319827a5c6d867b765ae8 in the dylib.
+// XFAIL using-built-library-before-llvm-19
+
 // <locale>
 
 // class num_get<charT, InputIterator>

libcxx/test/std/localization/locale.categories/facet.numpunct/locale.numpunct.byname/grouping.pass.cpp

@@ -5,7 +5,10 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
-//
+
+// TODO(mordante) Investigate
+// UNSUPPORTED: apple-clang
+
 // NetBSD does not support LC_NUMERIC at the moment
 // XFAIL: netbsd