cxx/test/input.output/iostream.format/input.streams/istream.unformatted/read.pass.cpp
Howard Hinnant b64f8b07c1 license change
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@119395 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-16 22:09:02 +00:00

82 lines
2.1 KiB
C++

//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <istream>
// basic_istream<charT,traits>& read(char_type* s, streamsize n);
#include <istream>
#include <cassert>
template <class CharT>
struct testbuf
: public std::basic_streambuf<CharT>
{
typedef std::basic_string<CharT> string_type;
typedef std::basic_streambuf<CharT> base;
private:
string_type str_;
public:
testbuf() {}
testbuf(const string_type& str)
: str_(str)
{
base::setg(const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data()),
const_cast<CharT*>(str_.data()) + str_.size());
}
CharT* eback() const {return base::eback();}
CharT* gptr() const {return base::gptr();}
CharT* egptr() const {return base::egptr();}
};
int main()
{
{
testbuf<char> sb(" 123456789");
std::istream is(&sb);
char s[5];
is.read(s, 5);
assert(!is.eof());
assert(!is.fail());
assert(std::string(s, 5) == " 1234");
assert(is.gcount() == 5);
is.read(s, 5);
assert( is.eof());
assert(!is.fail());
assert(std::string(s, 5) == "56789");
assert(is.gcount() == 5);
is.read(s, 5);
assert( is.eof());
assert( is.fail());
assert(is.gcount() == 0);
}
{
testbuf<wchar_t> sb(L" 123456789");
std::wistream is(&sb);
wchar_t s[5];
is.read(s, 5);
assert(!is.eof());
assert(!is.fail());
assert(std::wstring(s, 5) == L" 1234");
assert(is.gcount() == 5);
is.read(s, 5);
assert( is.eof());
assert(!is.fail());
assert(std::wstring(s, 5) == L"56789");
assert(is.gcount() == 5);
is.read(s, 5);
assert( is.eof());
assert( is.fail());
assert(is.gcount() == 0);
}
}