1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// <ostream>
10
11// template <class charT, class traits = char_traits<charT> >
12// class basic_ostream;
13
14// basic_ostream<charT,traits>& operator<<(ios_base& (*pf)(ios_base&));
15
16#include <ostream>
17#include <cassert>
18
19#include "test_macros.h"
20
21template <class CharT>
22class testbuf
23 : public std::basic_streambuf<CharT>
24{
25 typedef std::basic_streambuf<CharT> base;
26 std::basic_string<CharT> str_;
27public:
28 testbuf()
29 {
30 }
31
32 std::basic_string<CharT> str() const
33 {return std::basic_string<CharT>(base::pbase(), base::pptr());}
34
35protected:
36
37 virtual typename base::int_type
38 overflow(typename base::int_type ch = base::traits_type::eof())
39 {
40 if (ch != base::traits_type::eof())
41 {
42 int n = static_cast<int>(str_.size());
43 str_.push_back(static_cast<CharT>(ch));
44 str_.resize(str_.capacity());
45 base::setp(const_cast<CharT*>(str_.data()),
46 const_cast<CharT*>(str_.data() + str_.size()));
47 base::pbump(n+1);
48 }
49 return ch;
50 }
51};
52
53int main(int, char**)
54{
55 {
56 testbuf<char> sb;
57 std::ostream os(&sb);
58 assert(!(os.flags() & std::ios_base::uppercase));
59 os << std::uppercase;
60 assert( (os.flags() & std::ios_base::uppercase));
61 }
62
63 return 0;
64}
65

source code of libcxx/test/std/input.output/iostream.format/output.streams/ostream.formatted/ostream.inserters/ios_base.pass.cpp