25.lex.comparison.cpp

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#include <algorithm>    // for lexicographical_compare
#include <cstring>      // for strlen, size_t
 
#include <rw_alg_test.h>
#include <rw_value.h>      // for UserClass
#include <rw_driver.h>     // for rw_test()
 
 
_RWSTD_NAMESPACE (std) { 
 
#ifndef _RWSTD_NO_EXPLICIT_INSTANTIATION
 
// explicitly instantiate on types with minimum features
// to verify that the algorithm imposes no requirements
// beyond those specified
template
bool lexicographical_compare (InputIter<lt_comp<base<> > >, 
                              InputIter<lt_comp<base<> > >, 
                              InputIter<lt_comp<base<> > >, 
                              InputIter<lt_comp<base<> > >); 
template
bool lexicographical_compare (InputIter<base<> >, 
                              InputIter<base<> >, 
                              InputIter<base<> >, 
                              InputIter<base<> >,
                              binary_predicate<base<> >); 
 
#endif // _RWSTD_NO_EXPLICIT_INSTANTIATION
 
}   // namespace std
 
 
template <class T>
struct Less 
{
    static std::size_t funcalls_;
 
    // dummy arguments provided to prevent the class from being
    // default constructible and implicit conversion from int
    Less (int /* dummy */, int /* dummy */) {
        funcalls_ = 0;
    }
 
    // return a type other than bool but one that is implicitly
    // convertible to bool to detect incorrect assumptions
    conv_to_bool operator() (const T &x, const T &y) /* non-const */ {
        ++funcalls_;
        return conv_to_bool::make (x.data_.val_ < y.data_.val_);
    }
 
    static const char* name () { return "Less"; }
 
private:
    void operator= (Less&);   // not assignable
};
 
template<class T> std::size_t Less<T>::funcalls_;
 
 
// exercise lexicographical_compare 25.3.8
template 
<class T, class InputIterator1, class InputIterator2, class Predicate>
void test_lex_compare (int                   line,
                       const char           *src1,
                       const char           *src2,
                       bool                  res,
                       const InputIterator1 &it1,
                       const InputIterator2 &it2,
                       const T*,
                       const Predicate      *ppred)
{
    const char* const it1name = type_name (it1, (T*)0);
    const char* const it2name = type_name (it2, (T*)0);
    const char* const fname   = "lexicographical_compare";
    const char* const funname = Predicate::name ();
 
    const std::size_t nsrc1 = std::strlen (src1);
    const std::size_t nsrc2 = std::strlen (src2);
 
    T* const xsrc1 = T::from_char (src1, nsrc1);
    T* const xsrc2 = T::from_char (src2, nsrc2);
 
    T* const xsrc1_end = xsrc1 + nsrc1;
    T* const xsrc2_end = xsrc2 + nsrc2;
 
    const InputIterator1 first1 = make_iter (xsrc1,     xsrc1, xsrc1_end, it1);
    const InputIterator1 last1  = make_iter (xsrc1_end, xsrc1, xsrc1_end, it1);
    const InputIterator2 first2 = make_iter (xsrc2,     xsrc2, xsrc2_end, it2);
    const InputIterator2 last2  = make_iter (xsrc2_end, xsrc2, xsrc2_end, it2);
 
    const Predicate pred (0, 0);
 
    const std::size_t last_n_op_lt = T::n_total_op_lt_;
 
    const bool result = ppred ?
        std::lexicographical_compare (first1, last1, first2, last2, pred)
      : std::lexicographical_compare (first1, last1, first2, last2);
 
    // verify the returned value 25.3.8, p1 and p3: If two sequences have 
    // the same number of elements and their corresponding elements are 
    // equivalent, then neither sequence is  lexicographically less than
    // the other.
    rw_assert (res == result, 0, line,
               "line %d: %s<%s, %s%{?}, %s%{;}> (\"%s\", \"%s\", ...) "
               "== %b, got %b", 
               __LINE__, fname, it1name, it2name, 0 != ppred, funname,
               src1, src2, res, result);
 
    const std::size_t n_ops_lt = ppred ? 
        Predicate::funcalls_ : T::n_total_op_lt_ - last_n_op_lt;
 
    // verify the complexity 25.3.8, p2
    const std::size_t n_exp_ops = 2 * (nsrc1 < nsrc2 ? nsrc1 : nsrc2);
    rw_assert (n_ops_lt <= n_exp_ops, 0, line,
               "line %d: %s<%s, %s%{?}, %s%{;}> (\"%s\", \"%s\", ...) "
               "complexity: got %zu, expected no more than %zu",
               __LINE__, fname, it1name, it2name, 0 != ppred, funname,
               src1, src2, n_ops_lt, n_exp_ops);
 
    delete[] xsrc1;
    delete[] xsrc2;
}
 
template 
<class T, class InputIterator1, class InputIterator2, class Predicate>
void test_lex_compare (const InputIterator1 &it1,
                       const InputIterator2 &it2,
                       const T*,
                       const Predicate      *ppred)
{
    const char* const it1name  = type_name (it1, (T*)0);
    const char* const it2name  = type_name (it2, (T*)0);
    const char* const fname   = "lexicographical_compare";
    const char* const funname = Predicate::name();
 
    rw_info (0, 0, 0,
             "std::%s(%s, %2$s, %s, %3$s%{?}, %s%{;})",
             fname, it1name, it2name, 0 != ppred, funname);
 
#define TEST(src1, src2, res)                                               \
    test_lex_compare (__LINE__, src1, src2, res, it1, it2, (T*)0, ppred)
 
    TEST ("", "", false);
    TEST ("a", "", false);
    TEST ("", "a", true);
    TEST ("a", "a", false);
 
    TEST ("aa", "aa", false);
    TEST ("aa", "ab", true);
    TEST ("ba", "ab", false);
    TEST ("ba", "ba", false);
    TEST ("ba", "bc", true);
 
    TEST ("a", "abc", true);
    TEST ("a", "bcd", true);
    TEST ("a", "baed", true);
 
    TEST ("abcde", "abcdefghij", true);
    TEST ("fghij", "fghijabcde", true);
    TEST ("fghij", "abcdefghij", false);
    TEST ("cabed", "abcdeabcde", false);
 
    TEST ("abcdefghij", "abcdefghij", false);
    TEST ("fghijfghij", "abcdefghij", false);
    TEST ("fghijabcde", "abcdeabcde", false);
 
    TEST ("abcdefghij", "bacdfeghji", true);
    TEST ("bacdefghij", "bacdfeghji", true);
    TEST ("bacdfeghij", "bacdfeghji", true);
    TEST ("bacdfeghja", "bacdfeghji", true);
}
 
 
/* extern */ int rw_opt_no_predicate;           // --no-predicate
/* extern */ int rw_opt_no_input_iter;          // --no-InputIterator
/* extern */ int rw_opt_no_fwd_iter;            // --no-ForwardIterator
/* extern */ int rw_opt_no_bidir_iter;          // --no-BidirectionalIterator
/* extern */ int rw_opt_no_rnd_iter;            // --no-RandomAccessIterator
 
 
template <class T, class InputIterator1, class Predicate>
void test_lex_compare (const InputIterator1 &it1,
                       const T*,
                       const Predicate      *ppred)
{
    static const InputIter<T>        input_iter (0, 0, 0);
    static const FwdIter<T>          fwd_iter (0, 0, 0);
    static const BidirIter<T>        bidir_iter (0, 0, 0);
    static const RandomAccessIter<T> rand_iter (0, 0, 0);
 
    if (rw_opt_no_input_iter) {
        rw_note (0, __FILE__, __LINE__, "InputIterator test disabled");
    }
    else {
        test_lex_compare (it1, input_iter, (T*)0, ppred);
    }
 
    if (rw_opt_no_fwd_iter) {
        rw_note (0, __FILE__, __LINE__, "ForwardIterator test disabled");
    }
    else {
        test_lex_compare (it1, fwd_iter, (T*)0, ppred);
    }
 
    if (rw_opt_no_bidir_iter) {
        rw_note (0, __FILE__, __LINE__, "BidirectionalIterator test disabled");
    }
    else {
        test_lex_compare (it1, bidir_iter, (T*)0, ppred);
    }
 
    if (rw_opt_no_rnd_iter) {
        rw_note (0, __FILE__, __LINE__, "RandomAccessIterator test disabled");
    }
    else {
        test_lex_compare (it1, rand_iter, (T*)0, ppred);
    }
}
 
template <class T, class Predicate>
void test_lex_compare (const T*,
                       const Predicate *ppred)
{
    static const InputIter<T>        input_iter (0, 0, 0);
    static const FwdIter<T>          fwd_iter (0, 0, 0);
    static const BidirIter<T>        bidir_iter (0, 0, 0);
    static const RandomAccessIter<T> rand_iter (0, 0, 0);
 
    rw_info (0, 0, 0,
             "template <class %s, class %s%{?}, class %s%{;}> "
             "bool std::lexicographical_compare (%1$s, %1$s, %2$s, "
             "%2$s%{?}, %s%{;})",
             "InputIterator1", "InputIterator2", ppred, "Compare", 
             0 != ppred, "Compare");
 
    if (rw_opt_no_input_iter) {
        rw_note (0, __FILE__, __LINE__, "InputIterator test disabled");
    }
    else {
        test_lex_compare (input_iter, (T*)0, ppred);
    }
 
    if (rw_opt_no_fwd_iter) {
        rw_note (0, __FILE__, __LINE__, "ForwardIterator test disabled");
    }
    else {
        test_lex_compare (fwd_iter, (T*)0, ppred);
    }
 
    if (rw_opt_no_bidir_iter) {
        rw_note (0, __FILE__, __LINE__, "BidirectionalIterator test disabled");
    }
    else {
        test_lex_compare (bidir_iter, (T*)0, ppred);
    }
 
    if (rw_opt_no_rnd_iter) {
        rw_note (0, __FILE__, __LINE__, "RandomAccessIterator test disabled");
    }
    else {
        test_lex_compare (rand_iter, (T*)0, ppred);
    }
}
 
 
static int run_test (int, char*[])
{
    test_lex_compare ((UserClass*)0, (Less<UserClass>*)0); 
 
    if (rw_opt_no_predicate) {
        rw_note (0, __FILE__, __LINE__, 
                 "std::lexicographical_compare predicate test disabled");
    }
    else {
        test_lex_compare ((UserClass*)0, (Less<UserClass>*)1); 
    }
 
    return 0;
}
 
 
 
int main (int argc, char *argv[])
{
    return rw_test (argc, argv, __FILE__,
                    "lib.lex.comparison",
                    0 /* no comment */,
                    run_test,
                    "|-no-predicate#"
                    "|-no-InputIterator# "
                    "|-no-ForwardIterator# "
                    "|-no-BidirectionalIterator# "
                    "|-no-RandomAccessIterator#",
                    &rw_opt_no_predicate,
                    &rw_opt_no_input_iter,
                    &rw_opt_no_fwd_iter,
                    &rw_opt_no_bidir_iter,
                    &rw_opt_no_rnd_iter);
}