36         testbuf<char> sb("123");  in main()  local
37         sb.pbump(3);  in main()
38         assert(sb.underflow() == '1');  in main()
39         assert(sb.underflow() == '1');  in main()
40         assert(sb.snextc() == '2');  in main()
41         assert(sb.underflow() == '2');  in main()
42         assert(sb.underflow() == '2');  in main()
43         assert(sb.snextc() == '3');  in main()
44         assert(sb.underflow() == '3');  in main()
45         assert(sb.underflow() == '3');  in main()
46         assert(sb.snextc() == std::char_traits<char>::eof());  in main()
47         assert(sb.underflow() == std::char_traits<char>::eof());  in main()
48         assert(sb.underflow() == std::char_traits<char>::eof());  in main()
49         sb.sputc('4');  in main()
50         assert(sb.underflow() == '4');  in main()
51         assert(sb.underflow() == '4');  in main()
55         testbuf<wchar_t> sb(L"123");  in main()  local
56         sb.pbump(3);  in main()
57         assert(sb.underflow() == L'1');  in main()
58         assert(sb.underflow() == L'1');  in main()
59         assert(sb.snextc() == L'2');  in main()
60         assert(sb.underflow() == L'2');  in main()
61         assert(sb.underflow() == L'2');  in main()
62         assert(sb.snextc() == L'3');  in main()
63         assert(sb.underflow() == L'3');  in main()
64         assert(sb.underflow() == L'3');  in main()
65         assert(sb.snextc() == std::char_traits<wchar_t>::eof());  in main()
66         assert(sb.underflow() == std::char_traits<wchar_t>::eof());  in main()
67         assert(sb.underflow() == std::char_traits<wchar_t>::eof());  in main()
68         sb.sputc(L'4');  in main()
69         assert(sb.underflow() == L'4');  in main()
70         assert(sb.underflow() == L'4');  in main()