#include <streambuf>
#include <cassert>
int uflow_called = 0;
struct test
: public std::basic_streambuf<char>
{
typedef std::basic_streambuf<char> base;
test() {}
void setg(char* gbeg, char* gnext, char* gend)
{
base::setg(gbeg, gnext, gend);
}
protected:
int_type uflow()
{
++uflow_called;
return 'a';
}
};
int main()
{
{
test t;
assert(uflow_called == 0);
assert(t.sbumpc() == 'a');
assert(uflow_called == 1);
char in[] = "ABC";
t.setg(in, in, in+sizeof(in));
assert(t.sbumpc() == 'A');
assert(uflow_called == 1);
assert(t.sbumpc() == 'B');
assert(uflow_called == 1);
}
}