text: //===----------------------------------------------------------------------===//
  //
  // 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
  //
  //===----------------------------------------------------------------------===//
  
  // REQUIRES: locale.en_US.UTF-8
  
  // <iomanip>
  
  // template <class charT> T10 put_time(const struct tm* tmb, const charT* fmt);
  
  #include <iomanip>
  #include <ostream>
  #include <cassert>
  
  #include "test_macros.h"
  #include "platform_support.h" // locale name macros
  
  template <class CharT>
  class testbuf
      : public std::basic_streambuf<CharT>
  {
      typedef std::basic_streambuf<CharT> base;
      std::basic_string<CharT> str_;
  public:
      testbuf()
      {
      }
  
      std::basic_string<CharT> str() const
          {return std::basic_string<CharT>(base::pbase(), base::pptr());}
  
  protected:
  
      virtual typename base::int_type
          overflow(typename base::int_type ch = base::traits_type::eof())
          {
              if (ch != base::traits_type::eof())
              {
                  int n = static_cast<int>(str_.size());
                  str_.push_back(static_cast<CharT>(ch));
                  str_.resize(str_.capacity());
                  base::setp(const_cast<CharT*>(str_.data()),
                             const_cast<CharT*>(str_.data() + str_.size()));
                  base::pbump(n+1);
              }
              return ch;
          }
  };
  
  int main(int, char**)
  {
      {
          testbuf<char> sb;
          std::ostream os(&sb);
          os.imbue(std::locale(LOCALE_en_US_UTF_8));
          std::tm t = {};
          t.tm_sec = 59;
          t.tm_min = 55;
          t.tm_hour = 23;
          t.tm_mday = 31;
          t.tm_mon = 11;
          t.tm_year = 161;
          t.tm_wday = 6;
          t.tm_isdst = 0;
          os << std::put_time(&t, "%a %b %d %H:%M:%S %Y");
          assert(sb.str() == "Sat Dec 31 23:55:59 2061");
      }
      {
          testbuf<wchar_t> sb;
          std::wostream os(&sb);
          os.imbue(std::locale(LOCALE_en_US_UTF_8));
          std::tm t = {};
          t.tm_sec = 59;
          t.tm_min = 55;
          t.tm_hour = 23;
          t.tm_mday = 31;
          t.tm_mon = 11;
          t.tm_year = 161;
          t.tm_wday = 6;
          os << std::put_time(&t, L"%a %b %d %H:%M:%S %Y");
          assert(sb.str() == L"Sat Dec 31 23:55:59 2061");
      }
  
    return 0;
  }
  