diff options
Diffstat (limited to 'contrib/llvm-project/libcxx/include/__format/formatter_tuple.h')
| -rw-r--r-- | contrib/llvm-project/libcxx/include/__format/formatter_tuple.h | 122 |
1 files changed, 47 insertions, 75 deletions
diff --git a/contrib/llvm-project/libcxx/include/__format/formatter_tuple.h b/contrib/llvm-project/libcxx/include/__format/formatter_tuple.h index 82f5ada6e012..030097a8797d 100644 --- a/contrib/llvm-project/libcxx/include/__format/formatter_tuple.h +++ b/contrib/llvm-project/libcxx/include/__format/formatter_tuple.h @@ -11,18 +11,16 @@ #define _LIBCPP___FORMAT_FORMATTER_TUPLE_H #include <__algorithm/ranges_copy.h> -#include <__availability> #include <__chrono/statically_widen.h> #include <__config> +#include <__format/buffer.h> #include <__format/concepts.h> -#include <__format/format_args.h> #include <__format/format_context.h> #include <__format/format_error.h> #include <__format/format_parse_context.h> #include <__format/formatter.h> #include <__format/formatter_output.h> #include <__format/parser_std_format_spec.h> -#include <__iterator/back_insert_iterator.h> #include <__type_traits/remove_cvref.h> #include <__utility/integer_sequence.h> #include <__utility/pair.h> @@ -35,49 +33,52 @@ _LIBCPP_BEGIN_NAMESPACE_STD -#if _LIBCPP_STD_VER > 20 +#if _LIBCPP_STD_VER >= 23 template <__fmt_char_type _CharT, class _Tuple, formattable<_CharT>... _Args> -struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT __formatter_tuple { - _LIBCPP_HIDE_FROM_ABI constexpr void set_separator(basic_string_view<_CharT> __separator) { +struct _LIBCPP_TEMPLATE_VIS __formatter_tuple { + _LIBCPP_HIDE_FROM_ABI constexpr void set_separator(basic_string_view<_CharT> __separator) noexcept { __separator_ = __separator; } _LIBCPP_HIDE_FROM_ABI constexpr void - set_brackets(basic_string_view<_CharT> __opening_bracket, basic_string_view<_CharT> __closing_bracket) { + set_brackets(basic_string_view<_CharT> __opening_bracket, basic_string_view<_CharT> __closing_bracket) noexcept { __opening_bracket_ = __opening_bracket; __closing_bracket_ = __closing_bracket; } template <class _ParseContext> - _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __parse_ctx) { - const _CharT* __begin = __parser_.__parse(__parse_ctx, __format_spec::__fields_tuple); + _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) { + auto __begin = __parser_.__parse(__ctx, __format_spec::__fields_tuple); - // [format.tuple]/7 - // ... For each element e in underlying_, if e.set_debug_format() - // is a valid expression, calls e.set_debug_format(). - // TODO FMT this can be removed when P2733 is accepted. - std::__for_each_index_sequence(make_index_sequence<sizeof...(_Args)>(), [&]<size_t _Index> { - std::__set_debug_format(std::get<_Index>(__underlying_)); - }); - - const _CharT* __end = __parse_ctx.end(); - if (__begin == __end) - return __begin; - - if (*__begin == _CharT('m')) { + auto __end = __ctx.end(); + // Note 'n' is part of the type here + if (__parser_.__clear_brackets_) + set_brackets({}, {}); + else if (__begin != __end && *__begin == _CharT('m')) { if constexpr (sizeof...(_Args) == 2) { set_separator(_LIBCPP_STATICALLY_WIDEN(_CharT, ": ")); set_brackets({}, {}); ++__begin; } else - std::__throw_format_error("The format specifier m requires a pair or a two-element tuple"); - } else if (*__begin == _CharT('n')) { - set_brackets({}, {}); - ++__begin; + std::__throw_format_error("Type m requires a pair or a tuple with two elements"); } if (__begin != __end && *__begin != _CharT('}')) - std::__throw_format_error("The format-spec should consume the input or end with a '}'"); + std::__throw_format_error("The format specifier should consume the input or end with a '}'"); + + __ctx.advance_to(__begin); + + // [format.tuple]/7 + // ... For each element e in underlying_, if e.set_debug_format() + // is a valid expression, calls e.set_debug_format(). + std::__for_each_index_sequence(make_index_sequence<sizeof...(_Args)>(), [&]<size_t _Index> { + auto& __formatter = std::get<_Index>(__underlying_); + __formatter.parse(__ctx); + // Unlike the range_formatter we don't guard against evil parsers. Since + // this format-spec never has a format-spec for the underlying type + // adding the test would give additional overhead. + std::__set_debug_format(__formatter); + }); return __begin; } @@ -91,26 +92,25 @@ struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT __formatter_tuple { if (!__specs.__has_width()) return __format_tuple(__tuple, __ctx); - basic_string<_CharT> __str; - - // Since the output is written to a different iterator a new context is - // created. Since the underlying formatter uses the default formatting it - // doesn't need a locale or the formatting arguments. So creating a new - // context works. - // - // This solution works for this formatter, but it will not work for the - // range_formatter. In that patch a generic solution is work in progress. - // Once that is finished it can be used here. (The range_formatter will use - // these features so it's easier to add it there and then port it.) - // - // TODO FMT Use formatting wrapping used in the range_formatter. - basic_format_context __c = std::__format_context_create( - back_insert_iterator{__str}, - basic_format_args<basic_format_context<back_insert_iterator<basic_string<_CharT>>, _CharT>>{}); + // The size of the buffer needed is: + // - open bracket characters + // - close bracket character + // - n elements where every element may have a different size + // - (n -1) separators + // The size of the element is hard to predict, knowing the type helps but + // it depends on the format-spec. As an initial estimate we guess 6 + // characters. + // Typically both brackets are 1 character and the separator is 2 + // characters. Which means there will be + // (n - 1) * 2 + 1 + 1 = n * 2 character + // So estimate 8 times the range size as buffer. + __format::__retarget_buffer<_CharT> __buffer{8 * tuple_size_v<_Tuple>}; + basic_format_context<typename __format::__retarget_buffer<_CharT>::__iterator, _CharT> __c{ + __buffer.__make_output_iterator(), __ctx}; __format_tuple(__tuple, __c); - return __formatter::__write_string_no_precision(basic_string_view{__str}, __ctx.out(), __specs); + return __formatter::__write_string_no_precision(basic_string_view{__buffer.__view()}, __ctx.out(), __specs); } template <class _FormatContext> @@ -120,35 +120,7 @@ struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT __formatter_tuple { std::__for_each_index_sequence(make_index_sequence<sizeof...(_Args)>(), [&]<size_t _Index> { if constexpr (_Index) __ctx.advance_to(std::ranges::copy(__separator_, __ctx.out()).out); - - // During review Victor suggested to make the exposition only - // __underlying_ member a local variable. Currently the Standard - // requires nested debug-enabled formatter specializations not to - // output escaped output. P2733 fixes that bug, once accepted the - // code below can be used. - // (Note when a paper allows parsing a tuple-underlying-spec the - // exposition only member needs to be a class member. Earlier - // revisions of P2286 proposed that, but this was not pursued, - // due to time constrains and complexity of the matter.) - // TODO FMT This can be updated after P2733 is accepted. -# if 0 - // P2286 uses an exposition only member in the formatter - // tuple<formatter<remove_cvref_t<_Args>, _CharT>...> __underlying_; - // This was used in earlier versions of the paper since - // __underlying_.parse(...) was called. This is no longer the case - // so we can reduce the scope of the formatter. - // - // It does require the underlying's parse effect to be moved here too. - using _Arg = tuple_element<_Index, decltype(__tuple)>; - formatter<remove_cvref_t<_Args>, _CharT> __underlying; - - // [format.tuple]/7 - // ... For each element e in underlying_, if e.set_debug_format() - // is a valid expression, calls e.set_debug_format(). - std::__set_debug_format(__underlying); -# else __ctx.advance_to(std::get<_Index>(__underlying_).format(std::get<_Index>(__tuple), __ctx)); -# endif }); return std::ranges::copy(__closing_bracket_, __ctx.out()).out; @@ -164,14 +136,14 @@ private: }; template <__fmt_char_type _CharT, formattable<_CharT>... _Args> -struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT formatter<pair<_Args...>, _CharT> +struct _LIBCPP_TEMPLATE_VIS formatter<pair<_Args...>, _CharT> : public __formatter_tuple<_CharT, pair<_Args...>, _Args...> {}; template <__fmt_char_type _CharT, formattable<_CharT>... _Args> -struct _LIBCPP_TEMPLATE_VIS _LIBCPP_AVAILABILITY_FORMAT formatter<tuple<_Args...>, _CharT> +struct _LIBCPP_TEMPLATE_VIS formatter<tuple<_Args...>, _CharT> : public __formatter_tuple<_CharT, tuple<_Args...>, _Args...> {}; -#endif //_LIBCPP_STD_VER > 20 +#endif //_LIBCPP_STD_VER >= 23 _LIBCPP_END_NAMESPACE_STD |