[libc++] Add a script to automatize updating test for a new header.

[curdeius]

Summary

Idea from D92525.
This script globs include/ directory and updates the tests in test/libcxx.
This patch does not generate module.modulemap nor CMakeLists.txt.

[curdeius]

libcxx/docs/Contributing.rst

26–31

That's a drive-by fix.

[ldionne]

Another approach for generating those tests would be to instead insert just the header part between two markers. This would allow writing the new test mostly outside of the script, and only the header part would be inserted (between the markers) by the script. Something like this:

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

// Test that we can include each header in two TU's and link them together.

// RUN: %{cxx} -c %s -o %t.first.o %{flags} %{compile_flags}
// RUN: %{cxx} -c %s -o %t.second.o -DWITH_MAIN %{flags} %{compile_flags}
// RUN: %{cxx} -o %t.exe %t.first.o %t.second.o %{flags} %{link_flags}
// RUN: %{run}

// GCC 5 pretends it supports C++17 features, but some features like static_assert
// without a message are not actually supported. This causes some headers to fail
// when included.
// UNSUPPORTED: gcc-5 && c++17

// Prevent <ext/hash_map> from generating deprecated warnings for this test.
#if defined(__DEPRECATED)
#undef __DEPRECATED
#endif

//////////////////////////////////////////////////////////////////////////////
// BEGIN-GENERATED-HEADERS
//////////////////////////////////////////////////////////////////////////////

// ... This content is generated ...

//////////////////////////////////////////////////////////////////////////////
// END-GENERATED-HEADERS
//////////////////////////////////////////////////////////////////////////////

#if defined(WITH_MAIN)
int main(int, char**) { return 0; }
#endif

The main benefit of doing that is that the script could stay simple as we add more tests, and adding a new test might be only a matter of adding the path of the test in the script.

We'd have to find a way to accommodate stuff like using TEST_MACROS(); after each include, but one way we could do that is by always defining some macro like TEST_POST_INCLUDES in the test file before the generated content. It would always be empty, except when you want to include something after each header.

Do you have thoughts about this?

libcxx/docs/Contributing.rst

29

That doesn't seem right -- you don't need to modify <version> yourself, the script does it. Am I misunderstanding what you meant here?

38

I don't think it's necessary to keep the list of tests -- it'll only get out of date.

[curdeius]

I like your approach. It will indeed make it easier to add new tests and update current ones.

libcxx/docs/Contributing.rst

29

Oh, you're right. I thought it wasn't changing that.

38

OK. Will remove.

[curdeius]

Modify files between boundary markers.
I haven't modified the way TEST_MACROS() stuff is done though. I'd be inclined to rethink it if it becomes a problem and we have more tests.

[ldionne]

Love it! Thanks for the automation!

[curdeius]

• Minor change: move clang-format comments into the generated part.

libcxx/docs/Contributing.rst

 =================
 
 After branching for an LLVM release:
 
 1. Update ``_LIBCPP_VERSION`` in ``include/__config``
 2. Update the ``include/__libcpp_version`` file
 3. Update the version number in ``docs/conf.py``
 
+Modifying feature test macros
+=============================
+
+When adding or updating feature test macros, you should update the corresponding tests.
+To do that, modify ``feature_test_macros`` table in the script ``utils/generate_feature_test_macro_components.py``, run it, and commit updated files.
+
 Adding a new header TODO
 ========================
 
 When adding a new header to libc++:
 
 1. Add a test under ``test/libcxx`` that the new header defines ``_LIBCPP_VERSION``. See ``test/libcxx/algorithms/version.pass.cpp`` for an example.
-2. Update the following test files to include the new header:
-
-  * ``test/libcxx/double_include.sh.cpp``
-  * ``test/libcxx/min_max_macros.compile.pass.cpp``
-  * ``test/libcxx/no_assert_include.compile.pass.cpp``
-
+2. Run ``python utils/generate_header_tests.py``, verify and commit the modifications.
 3. Create a submodule in ``include/module.modulemap`` for the new header.
 4. Update the ``include/CMakeLists.txt`` file to include the new header.
 
 Exporting new symbols from the library
 ======================================
 
 When exporting new symbols from libc++, one must update the ABI lists located in ``lib/abi``.
 To test whether the lists are up-to-date, please run the target ``check-cxx-abilist``.
 To regenerate the lists, use the target ``generate-cxx-abilist``.

libcxx/test/libcxx/double_include.sh.cpp

 // RUN: %{cxx} -o %t.exe %t.first.o %t.second.o %{flags} %{link_flags}
 // RUN: %{run}
 
 // GCC 5 pretends it supports C++17 features, but some features like static_assert
 // without a message are not actually supported. This causes some headers to fail
 // when included.
 // UNSUPPORTED: gcc-5 && c++17
 
+// clang-format off
+
 // Prevent <ext/hash_map> from generating deprecated warnings for this test.
 #if defined(__DEPRECATED)
-#undef __DEPRECATED
+#    undef __DEPRECATED
 #endif
 
+////////////////////////////////////////////////////////////////////////////////
+// BEGIN-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+
+// WARNING: This test was generated by generate_header_tests.py
+// and should not be edited manually.
+
 // Top level headers
 #include <algorithm>
 #include <any>
 #include <array>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <atomic>
+#    include <atomic>
 #endif
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <barrier>
+#    include <barrier>
 #endif
 #include <bit>
 #include <bitset>
 #include <cassert>
 #include <ccomplex>
 #include <cctype>
 #include <cerrno>
 #include <cfenv>
 #include <cfloat>
 #include <charconv>
 #include <chrono>
 #include <cinttypes>
 #include <ciso646>
 #include <climits>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <clocale>
+#endif
 #include <cmath>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <codecvt>
+#endif
 #include <compare>
 #include <complex>
 #include <complex.h>
 #include <concepts>
 #include <condition_variable>
 #include <csetjmp>
 #include <csignal>
 #include <cstdarg>

 #include <deque>
 #include <errno.h>
 #include <exception>
 #include <execution>
 #include <fenv.h>
 #include <filesystem>
 #include <float.h>
 #include <forward_list>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <fstream>
+#endif
 #include <functional>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <future>
+#    include <future>
 #endif
 #include <initializer_list>
 #include <inttypes.h>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <iomanip>
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <ios>
+#endif
 #include <iosfwd>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <iostream>
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <istream>
+#endif
 #include <iterator>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <latch>
+#    include <latch>
 #endif
 #include <limits>
 #include <limits.h>
 #include <list>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <locale>
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <locale.h>
+#endif
 #include <map>
 #include <math.h>
 #include <memory>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <mutex>
+#    include <mutex>
 #endif
 #include <new>
 #include <numbers>
 #include <numeric>
 #include <optional>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <ostream>
+#endif
 #include <queue>
 #include <random>
 #include <ratio>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <regex>
+#endif
 #include <scoped_allocator>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <semaphore>
+#    include <semaphore>
 #endif
 #include <set>
 #include <setjmp.h>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <shared_mutex>
+#    include <shared_mutex>
 #endif
 #include <span>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <sstream>
+#endif
 #include <stack>
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdexcept>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <streambuf>
+#endif
 #include <string>
 #include <string.h>
 #include <string_view>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <strstream>
+#endif
 #include <system_error>
 #include <tgmath.h>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <thread>
+#    include <thread>
 #endif
 #include <tuple>
 #include <typeindex>
 #include <typeinfo>
 #include <type_traits>
 #include <unordered_map>
 #include <unordered_set>
 #include <utility>
 #include <valarray>
 #include <variant>
 #include <vector>
 #include <version>
 #include <wchar.h>
 #include <wctype.h>
 
-#ifndef _LIBCPP_HAS_NO_LOCALIZATION
-#   include <clocale>
-#   include <codecvt>
-#   include <fstream>
-#   include <iomanip>
-#   include <ios>
-#   include <iostream>
-#   include <istream>
-#   include <locale.h>
-#   include <locale>
-#   include <ostream>
-#   include <regex>
-#   include <sstream>
-#   include <streambuf>
-#   include <strstream>
-#   if __cplusplus >= 201103L
-#       include <experimental/regex>
-#   endif
-#endif
-
 // experimental headers
 #if __cplusplus >= 201103L
-#include <experimental/algorithm>
-#if defined(__cpp_coroutines)
-#include <experimental/coroutine>
-#endif
-#include <experimental/deque>
-#include <experimental/filesystem>
-#include <experimental/forward_list>
-#include <experimental/functional>
-#include <experimental/iterator>
-#include <experimental/list>
-#include <experimental/map>
-#include <experimental/memory_resource>
-#include <experimental/propagate_const>
-#include <experimental/set>
-#include <experimental/simd>
-#include <experimental/string>
-#include <experimental/type_traits>
-#include <experimental/unordered_map>
-#include <experimental/unordered_set>
-#include <experimental/utility>
-#include <experimental/vector>
+#    include <experimental/algorithm>
+#    if defined(__cpp_coroutines)
+#        include <experimental/coroutine>
+#    endif
+#    include <experimental/deque>
+#    include <experimental/filesystem>
+#    include <experimental/forward_list>
+#    include <experimental/functional>
+#    include <experimental/iterator>
+#    include <experimental/list>
+#    include <experimental/map>
+#    include <experimental/memory_resource>
+#    include <experimental/propagate_const>
+#    ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#        include <experimental/regex>
+#    endif
+#    include <experimental/set>
+#    include <experimental/simd>
+#    include <experimental/string>
+#    include <experimental/type_traits>
+#    include <experimental/unordered_map>
+#    include <experimental/unordered_set>
+#    include <experimental/utility>
+#    include <experimental/vector>
 #endif // __cplusplus >= 201103L
 
 // extended headers
 #include <ext/hash_map>
 #include <ext/hash_set>
 
+////////////////////////////////////////////////////////////////////////////////
+// END-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+
 #if defined(WITH_MAIN)
 int main(int, char**) { return 0; }
 #endif

libcxx/test/libcxx/min_max_macros.compile.pass.cpp

 // -*- C++ -*-
 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 // Test that headers are not tripped up by the surrounding code defining the
 // min() and max() macros.
 
 // GCC 5 has incomplete support for C++17, so some headers fail when included.
 // UNSUPPORTED: gcc-5 && c++17
 
+// clang-format off
+
 // Prevent <ext/hash_map> from generating deprecated warnings for this test.
 #if defined(__DEPRECATED)
-#undef __DEPRECATED
+#    undef __DEPRECATED
 #endif
 
 #define TEST_MACROS() static_assert(min() == true && max() == true, "")
 #define min() true
 #define max() true
 
+////////////////////////////////////////////////////////////////////////////////
+// BEGIN-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+
+// WARNING: This test was generated by generate_header_tests.py
+// and should not be edited manually.
+
 // Top level headers
 #include <algorithm>
 TEST_MACROS();
 #include <any>
 TEST_MACROS();
 #include <array>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <atomic>
+#    include <atomic>
 TEST_MACROS();
 #endif
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <barrier>
+#    include <barrier>
 TEST_MACROS();
 #endif
 #include <bit>
 TEST_MACROS();
 #include <bitset>
 TEST_MACROS();
 #include <cassert>
 TEST_MACROS();

 #include <chrono>
 TEST_MACROS();
 #include <cinttypes>
 TEST_MACROS();
 #include <ciso646>
 TEST_MACROS();
 #include <climits>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <clocale>
+TEST_MACROS();
+#endif
 #include <cmath>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <codecvt>
+TEST_MACROS();
+#endif
 #include <compare>
 TEST_MACROS();
 #include <complex>
 TEST_MACROS();
 #include <complex.h>
 TEST_MACROS();
 #include <concepts>
 TEST_MACROS();

 #include <fenv.h>
 TEST_MACROS();
 #include <filesystem>
 TEST_MACROS();
 #include <float.h>
 TEST_MACROS();
 #include <forward_list>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <fstream>
+TEST_MACROS();
+#endif
 #include <functional>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <future>
+#    include <future>
 TEST_MACROS();
 #endif
 #include <initializer_list>
 TEST_MACROS();
 #include <inttypes.h>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <iomanip>
+TEST_MACROS();
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <ios>
+TEST_MACROS();
+#endif
 #include <iosfwd>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <iostream>
+TEST_MACROS();
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <istream>
+TEST_MACROS();
+#endif
 #include <iterator>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <latch>
+#    include <latch>
 TEST_MACROS();
 #endif
 #include <limits>
 TEST_MACROS();
 #include <limits.h>
 TEST_MACROS();
 #include <list>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <locale>
+TEST_MACROS();
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <locale.h>
+TEST_MACROS();
+#endif
 #include <map>
 TEST_MACROS();
 #include <math.h>
 TEST_MACROS();
 #include <memory>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <mutex>
+#    include <mutex>
 TEST_MACROS();
 #endif
 #include <new>
 TEST_MACROS();
 #include <numbers>
 TEST_MACROS();
 #include <numeric>
 TEST_MACROS();
 #include <optional>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <ostream>
+TEST_MACROS();
+#endif
 #include <queue>
 TEST_MACROS();
 #include <random>
 TEST_MACROS();
 #include <ratio>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <regex>
+TEST_MACROS();
+#endif
 #include <scoped_allocator>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <semaphore>
+#    include <semaphore>
 TEST_MACROS();
 #endif
 #include <set>
 TEST_MACROS();
 #include <setjmp.h>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <shared_mutex>
+#    include <shared_mutex>
 TEST_MACROS();
 #endif
 #include <span>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <sstream>
+TEST_MACROS();
+#endif
 #include <stack>
 TEST_MACROS();
 #include <stdbool.h>
 TEST_MACROS();
 #include <stddef.h>
 TEST_MACROS();
 #include <stdexcept>
 TEST_MACROS();
 #include <stdint.h>
 TEST_MACROS();
 #include <stdio.h>
 TEST_MACROS();
 #include <stdlib.h>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <streambuf>
+TEST_MACROS();
+#endif
 #include <string>
 TEST_MACROS();
 #include <string.h>
 TEST_MACROS();
 #include <string_view>
 TEST_MACROS();
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <strstream>
+TEST_MACROS();
+#endif
 #include <system_error>
 TEST_MACROS();
 #include <tgmath.h>
 TEST_MACROS();
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <thread>
+#    include <thread>
 TEST_MACROS();
 #endif
 #include <tuple>
 TEST_MACROS();
 #include <typeindex>
 TEST_MACROS();
 #include <typeinfo>
 TEST_MACROS();

 TEST_MACROS();
 #include <version>
 TEST_MACROS();
 #include <wchar.h>
 TEST_MACROS();
 #include <wctype.h>
 TEST_MACROS();
 
-#ifndef _LIBCPP_HAS_NO_LOCALIZATION
-#   include <clocale>
-    TEST_MACROS();
-#   include <codecvt>
-    TEST_MACROS();
-#   include <fstream>
-    TEST_MACROS();
-#   include <iomanip>
-    TEST_MACROS();
-#   include <ios>
-    TEST_MACROS();
-#   include <iostream>
-    TEST_MACROS();
-#   include <istream>
-    TEST_MACROS();
-#   include <locale>
-    TEST_MACROS();
-#   include <locale.h>
-    TEST_MACROS();
-#   include <ostream>
-    TEST_MACROS();
-#   include <regex>
-    TEST_MACROS();
-#   include <sstream>
-    TEST_MACROS();
-#   include <streambuf>
-    TEST_MACROS();
-#   include <strstream>
-    TEST_MACROS();
-#   if __cplusplus >= 201103L
-#       include <experimental/regex>
-        TEST_MACROS();
-#   endif
-#endif
-
 // experimental headers
 #if __cplusplus >= 201103L
-#include <experimental/algorithm>
+#    include <experimental/algorithm>
 TEST_MACROS();
-#if defined(__cpp_coroutines)
-#include <experimental/coroutine>
+#    if defined(__cpp_coroutines)
+#        include <experimental/coroutine>
 TEST_MACROS();
-#endif
-#include <experimental/deque>
+#    endif
+#    include <experimental/deque>
 TEST_MACROS();
-#include <experimental/filesystem>
+#    include <experimental/filesystem>
 TEST_MACROS();
-#include <experimental/forward_list>
+#    include <experimental/forward_list>
 TEST_MACROS();
-#include <experimental/functional>
+#    include <experimental/functional>
 TEST_MACROS();
-#include <experimental/iterator>
+#    include <experimental/iterator>
 TEST_MACROS();
-#include <experimental/list>
+#    include <experimental/list>
 TEST_MACROS();
-#include <experimental/map>
+#    include <experimental/map>
 TEST_MACROS();
-#include <experimental/memory_resource>
+#    include <experimental/memory_resource>
 TEST_MACROS();
-#include <experimental/propagate_const>
+#    include <experimental/propagate_const>
 TEST_MACROS();
-#include <experimental/set>
+#    ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#        include <experimental/regex>
+TEST_MACROS();
+#    endif
+#    include <experimental/set>
 TEST_MACROS();
-#include <experimental/simd>
+#    include <experimental/simd>
 TEST_MACROS();
-#include <experimental/string>
+#    include <experimental/string>
 TEST_MACROS();
-#include <experimental/type_traits>
+#    include <experimental/type_traits>
 TEST_MACROS();
-#include <experimental/unordered_map>
+#    include <experimental/unordered_map>
 TEST_MACROS();
-#include <experimental/unordered_set>
+#    include <experimental/unordered_set>
 TEST_MACROS();
-#include <experimental/utility>
+#    include <experimental/utility>
 TEST_MACROS();
-#include <experimental/vector>
+#    include <experimental/vector>
 TEST_MACROS();
 #endif // __cplusplus >= 201103L
 
 // extended headers
 #include <ext/hash_map>
 TEST_MACROS();
 #include <ext/hash_set>
 TEST_MACROS();
+
+////////////////////////////////////////////////////////////////////////////////
+// END-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////

libcxx/test/libcxx/no_assert_include.compile.pass.cpp

 // -*- C++ -*-
 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 // Ensure that none of the standard C++ headers implicitly include cassert or
 // assert.h (because assert() is implemented as a macro).
 
 // GCC 5 has incomplete support for C++17, so some headers fail when included.
 // UNSUPPORTED: gcc-5 && c++17
 
+// clang-format off
+
 // Prevent <ext/hash_map> from generating deprecated warnings for this test.
 #if defined(__DEPRECATED)
-#undef __DEPRECATED
+#    undef __DEPRECATED
 #endif
 
+////////////////////////////////////////////////////////////////////////////////
+// BEGIN-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+
+// WARNING: This test was generated by generate_header_tests.py
+// and should not be edited manually.
+
 // Top level headers
 #include <algorithm>
 #include <any>
 #include <array>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <atomic>
+#    include <atomic>
 #endif
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <barrier>
+#    include <barrier>
 #endif
 #include <bit>
 #include <bitset>
 #include <ccomplex>
 #include <cctype>
 #include <cerrno>
 #include <cfenv>
 #include <cfloat>
 #include <charconv>
 #include <chrono>
 #include <cinttypes>
 #include <ciso646>
 #include <climits>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <clocale>
+#endif
 #include <cmath>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <codecvt>
+#endif
 #include <compare>
 #include <complex>
 #include <complex.h>
 #include <concepts>
 #include <condition_variable>
 #include <csetjmp>
 #include <csignal>
 #include <cstdarg>

 #include <deque>
 #include <errno.h>
 #include <exception>
 #include <execution>
 #include <fenv.h>
 #include <filesystem>
 #include <float.h>
 #include <forward_list>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <fstream>
+#endif
 #include <functional>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <future>
+#    include <future>
 #endif
 #include <initializer_list>
 #include <inttypes.h>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <iomanip>
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <ios>
+#endif
 #include <iosfwd>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <iostream>
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <istream>
+#endif
 #include <iterator>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <latch>
+#    include <latch>
 #endif
 #include <limits>
 #include <limits.h>
 #include <list>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <locale>
+#endif
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <locale.h>
+#endif
 #include <map>
 #include <math.h>
 #include <memory>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <mutex>
+#    include <mutex>
 #endif
 #include <new>
 #include <numbers>
 #include <numeric>
 #include <optional>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <ostream>
+#endif
 #include <queue>
 #include <random>
 #include <ratio>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <regex>
+#endif
 #include <scoped_allocator>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <semaphore>
+#    include <semaphore>
 #endif
 #include <set>
 #include <setjmp.h>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <shared_mutex>
+#    include <shared_mutex>
 #endif
 #include <span>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <sstream>
+#endif
 #include <stack>
 #include <stdbool.h>
 #include <stddef.h>
 #include <stdexcept>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <streambuf>
+#endif
 #include <string>
 #include <string.h>
 #include <string_view>
+#ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#    include <strstream>
+#endif
 #include <system_error>
 #include <tgmath.h>
 #ifndef _LIBCPP_HAS_NO_THREADS
-#include <thread>
+#    include <thread>
 #endif
 #include <tuple>
 #include <typeindex>
 #include <typeinfo>
 #include <type_traits>
 #include <unordered_map>
 #include <unordered_set>
 #include <utility>
 #include <valarray>
 #include <variant>
 #include <vector>
 #include <version>
 #include <wchar.h>
 #include <wctype.h>
 
-#ifndef _LIBCPP_HAS_NO_LOCALIZATION
-#   include <clocale>
-#   include <codecvt>
-#   include <fstream>
-#   include <iomanip>
-#   include <ios>
-#   include <iostream>
-#   include <istream>
-#   include <locale>
-#   include <locale.h>
-#   include <ostream>
-#   include <regex>
-#   include <sstream>
-#   include <streambuf>
-#   include <strstream>
-#   if __cplusplus >= 201103L
-#       include <experimental/regex>
-#   endif
-#endif
-
 // experimental headers
 #if __cplusplus >= 201103L
-#include <experimental/algorithm>
-#if defined(__cpp_coroutines)
-#include <experimental/coroutine>
-#endif
-#include <experimental/deque>
-#include <experimental/filesystem>
-#include <experimental/forward_list>
-#include <experimental/functional>
-#include <experimental/iterator>
-#include <experimental/list>
-#include <experimental/map>
-#include <experimental/memory_resource>
-#include <experimental/propagate_const>
-#include <experimental/set>
-#include <experimental/simd>
-#include <experimental/string>
-#include <experimental/type_traits>
-#include <experimental/unordered_map>
-#include <experimental/unordered_set>
-#include <experimental/utility>
-#include <experimental/vector>
+#    include <experimental/algorithm>
+#    if defined(__cpp_coroutines)
+#        include <experimental/coroutine>
+#    endif
+#    include <experimental/deque>
+#    include <experimental/filesystem>
+#    include <experimental/forward_list>
+#    include <experimental/functional>
+#    include <experimental/iterator>
+#    include <experimental/list>
+#    include <experimental/map>
+#    include <experimental/memory_resource>
+#    include <experimental/propagate_const>
+#    ifndef _LIBCPP_HAS_NO_LOCALIZATION
+#        include <experimental/regex>
+#    endif
+#    include <experimental/set>
+#    include <experimental/simd>
+#    include <experimental/string>
+#    include <experimental/type_traits>
+#    include <experimental/unordered_map>
+#    include <experimental/unordered_set>
+#    include <experimental/utility>
+#    include <experimental/vector>
 #endif // __cplusplus >= 201103L
 
 // extended headers
 #include <ext/hash_map>
 #include <ext/hash_set>
 
+////////////////////////////////////////////////////////////////////////////////
+// END-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+
 #ifdef assert
 #error "Do not include cassert or assert.h in standard header files"
 #endif

libcxx/utils/generate_header_tests.py

+#!/usr/bin/env python
+
+import glob
+import os
+import posixpath
+import re
+
+
+def get_libcxx_paths():
+    utils_path = os.path.dirname(os.path.abspath(__file__))
+    script_name = os.path.basename(__file__)
+    assert os.path.exists(utils_path)
+    src_root = os.path.dirname(utils_path)
+    include_path = os.path.join(src_root, 'include')
+    assert os.path.exists(include_path)
+    libcxx_test_path = os.path.join(src_root, 'test', 'libcxx')
+    assert os.path.exists(libcxx_test_path)
+    return script_name, src_root, include_path, libcxx_test_path
+
+
+script_name, source_root, include_path, libcxx_test_path = get_libcxx_paths()
+
+header_markup = {
+    "atomic": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "barrier": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "future": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "latch": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "mutex": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "shared_mutex": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "semaphore": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+    "thread": ["ifndef _LIBCPP_HAS_NO_THREADS"],
+
+    "clocale": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "codecvt": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "fstream": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "iomanip": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "ios": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "iostream": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "istream": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "locale": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "locale.h": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "ostream": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "regex": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "sstream": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "streambuf": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+    "strstream": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+
+    "experimental/coroutine": ["if defined(__cpp_coroutines)"],
+    "experimental/regex": ["ifndef _LIBCPP_HAS_NO_LOCALIZATION"],
+}
+
+allowed_extensions = ['', '.h']
+indent_width = 4
+
+
+begin_pattern = """\
+////////////////////////////////////////////////////////////////////////////////
+// BEGIN-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+"""
+
+warning_note = """\
+// WARNING: This test was generated by {script_name}
+// and should not be edited manually.
+
+""".format(script_name=script_name)
+
+end_pattern = """\
+////////////////////////////////////////////////////////////////////////////////
+// END-GENERATED-HEADERS
+////////////////////////////////////////////////////////////////////////////////
+"""
+
+generated_part_pattern = re.compile(re.escape(begin_pattern) + ".*" + re.escape(end_pattern),
+                                    re.MULTILINE | re.DOTALL)
+
+headers_template = """\
+// Top level headers
+{top_level_headers}
+
+// experimental headers
+#if __cplusplus >= 201103L
+{experimental_headers}
+#endif // __cplusplus >= 201103L
+
+// extended headers
+{extended_headers}
+"""
+
+
+def should_keep_header(p, exclusions=None):
+    if os.path.isdir(p):
+        return False
+
+    if exclusions:
+        relpath = os.path.relpath(p, include_path)
+        relpath = posixpath.join(*os.path.split(relpath))
+        if relpath in exclusions:
+            print('Excluded file:', relpath)
+            return False
+
+    return os.path.splitext(p)[1] in allowed_extensions
+
+
+def produce_include(relpath, indent_level, post_include=None):
+    relpath = posixpath.join(*os.path.split(relpath))
+    template = "{preambule}#{indentation}include <{include}>{post_include}{postambule}"
+
+    base_indentation = ' '*(indent_width * indent_level)
+    next_indentation = base_indentation + ' '*(indent_width)
+    post_include = "\n{}".format(post_include) if post_include else ''
+
+    markup = header_markup.get(relpath, None)
+    if markup:
+        preambule = '#{indentation}{directive}\n'.format(
+            directive=markup[0],
+            indentation=base_indentation,
+        )
+        postambule = '\n#{indentation}endif'.format(
+            indentation=base_indentation,
+        )
+        indentation = next_indentation
+    else:
+        preambule = ''
+        postambule = ''
+        indentation = base_indentation
+
+    return template.format(
+        include=relpath,
+        post_include=post_include,
+        preambule=preambule,
+        postambule=postambule,
+        indentation=indentation,
+    )
+
+
+def produce_headers(path_parts, indent_level, post_include=None, exclusions=None):
+    pattern = os.path.join(*path_parts, '[a-z]*')
+
+    include_headers = glob.glob(pattern, recursive=False)
+
+    include_headers = [
+        produce_include(os.path.relpath(p, include_path),
+                        indent_level, post_include=post_include)
+        for p in include_headers
+        if should_keep_header(p, exclusions)]
+
+    return '\n'.join(include_headers)
+
+
+def produce_top_level_headers(post_include=None, exclusions=None):
+    return produce_headers([include_path], 0, post_include=post_include, exclusions=exclusions)
+
+
+def produce_experimental_headers(post_include=None, exclusions=None):
+    return produce_headers([include_path, 'experimental'], 1, post_include=post_include, exclusions=exclusions)
+
+
+def produce_extended_headers(post_include=None, exclusions=None):
+    return produce_headers([include_path, 'ext'], 0, post_include=post_include, exclusions=exclusions)
+
+
+def replace_generated_headers(test_path, test_str):
+    with open(test_path, 'r') as f:
+        content = f.read()
+
+    content = generated_part_pattern.sub(begin_pattern + '\n' + warning_note + test_str +
+                                         '\n' + end_pattern, content)
+
+    with open(test_path, 'w') as f:
+        f.write(content)
+
+
+def produce_test(test_filename, exclusions=None, post_include=None):
+    test_str = headers_template.format(
+        top_level_headers=produce_top_level_headers(
+            post_include=post_include,
+            exclusions=exclusions,
+        ),
+        experimental_headers=produce_experimental_headers(
+            post_include=post_include,
+        ),
+        extended_headers=produce_extended_headers(
+            post_include=post_include,
+        ),
+    )
+
+    replace_generated_headers(os.path.join(
+        libcxx_test_path, test_filename), test_str)
+
+
+def main():
+    produce_test('double_include.sh.cpp')
+    produce_test('min_max_macros.compile.pass.cpp',
+                 post_include='TEST_MACROS();')
+    produce_test('no_assert_include.compile.pass.cpp',
+                 exclusions=['cassert'])
+
+
+if __name__ == '__main__':
+    main()