25.set.intersection.cpp

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#include <algorithm>    // for set_intersection 
#include <cstddef>      // for size_t
 
#include <rw_alg_test.h>
#include <rw_value.h>   // for UserClass
#include <rw_driver.h>  // for rw_test()
 
 
_RWSTD_NAMESPACE (std) { 
 
// disable explicit instantiation for compilers (like MSVC)
// that can't handle it
#ifndef _RWSTD_NO_EXPLICIT_INSTANTIATION
 
template 
OutputIter<lt_comp<assign<base<cpy_ctor> > > >
set_intersection (InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  OutputIter<lt_comp<assign<base<cpy_ctor> > > >);
 
template 
OutputIter<lt_comp<assign<base<cpy_ctor> > > >
set_intersection (InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  InputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  OutputIter<lt_comp<assign<base<cpy_ctor> > > >,
                  binary_predicate<lt_comp<assign<base<cpy_ctor> > > >);
 
#endif // _RWSTD_NO_EXPLICIT_INSTANTIATION
 
}   // namespace std
 
 
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 UserClass &x,
                             const UserClass &y) /* non-const */ {
        ++funcalls_;
        return conv_to_bool::make (x.data_.val_ < y.data_.val_);
    }
 
private:
    void operator= (Less&);   // not assignable
};
 
std::size_t Less::funcalls_;
 
 
struct SetIntersectionBase
{
    virtual ~SetIntersectionBase() {}
 
    const char* iter_names [3];
 
    // pure virtual
    virtual UserClass*
    set_intersection (const UserClass*, const UserClass*, const UserClass*,
                      const UserClass*, UserClass*, UserClass*,
                      const Less*) const = 0;
};
 
template <class InputIterator1, class InputIterator2, class OutputIterator>
struct SetIntersection: SetIntersectionBase
{
    SetIntersection () {
        iter_names [0] = type_name (InputIterator1 (0, 0, 0), (UserClass*)0);
        iter_names [1] = type_name (InputIterator2 (0, 0, 0), (UserClass*)0);
        iter_names [2] = type_name (OutputIterator (0, 0, 0), (UserClass*)0);
    }
 
    virtual UserClass*
    set_intersection (const UserClass    *xsrc1, const UserClass *xsrc1_end,
                      const UserClass    *xsrc2, const UserClass *xsrc2_end,
                      UserClass          *xdst,  UserClass       *xdst_end,
                      const Less *ppred) const {
 
        const InputIterator1 first1 (xsrc1,     xsrc1, xsrc1_end);
        const InputIterator1 last1  (xsrc1_end, xsrc1, xsrc1_end);
        const InputIterator2 first2 (xsrc2,     xsrc2, xsrc2_end);
        const InputIterator2 last2  (xsrc2_end, xsrc2, xsrc2_end);
 
        const OutputIterator result (xdst, xdst, xdst_end);
 
        const OutputIterator ret = ppred ?
              std::set_intersection (first1, last1, first2, 
                                     last2, result, *ppred)
            : std::set_intersection (first1, last1, first2, 
                                     last2, result);
 
        // silence EDG eccp 3.7 and prior remark #550-D:
        //   variable was set but never used
        _RWSTD_UNUSED (ret);
 
        return ret.cur_;
    }
};
 
 
void test_set_intersection (int                        line,
                            const char                *src1,
                            std::size_t                nsrc1,
                            const char                *src2,
                            std::size_t                nsrc2,
                            const char                *res,
                            std::size_t                ndst,
                            bool                       predicate,
                            const SetIntersectionBase &alg)
{
    const char* const it1name = alg.iter_names [0];
    const char* const it2name = alg.iter_names [1];
    const char* const outname = alg.iter_names [2];
    const char* const fname   = "set_intersection";
    const char* const funname = predicate ? "Less" : 0;
 
    UserClass* const xsrc1 = UserClass::from_char (src1, nsrc1,
                                                   true /* must be sorted */);
    UserClass* const xsrc2 = UserClass::from_char (src2, nsrc2,
                                                   true /* must be sorted */);
 
    // assert that the sequences have been successfully created
    RW_ASSERT (0 == nsrc1 || xsrc1);
    RW_ASSERT (0 == nsrc2 || xsrc2);
 
    UserClass* const xdst = new UserClass [ndst];
 
    const int max1_id = nsrc1 > 0 ? xsrc1[nsrc1 - 1].id_ : -1;
 
    UserClass* const xsrc1_end = xsrc1 + nsrc1;
    UserClass* const xsrc2_end = xsrc2 + nsrc2;
    UserClass* const xdst_end  = xdst + ndst;
 
    const std::size_t last_n_op_lt = UserClass::n_total_op_lt_;
 
    const Less pred (0, 0);
    const Less* const ppred = predicate ? &pred : 0;
 
    const UserClass* const xdst_res =
        alg.set_intersection (xsrc1, xsrc1_end, xsrc2, 
                              xsrc2_end, xdst, xdst_end, ppred);
 
    // check the returned value
    bool success = xdst_res == xdst_end;
    rw_assert (success, 0, line,
               "line %d: %s<%s, %s, %s%{?}, %s%{;}> (\"%s\", \"%s\", ...) "
               "got res + %td, expected res + %zu", 
               __LINE__, fname, it1name, it2name, outname, predicate, 
               funname, src1, src2, xdst_res - xdst, ndst);
 
    // quit here to avoid the running out of the array boundaries
    if (!success) {    
        delete[] xsrc1;
        delete[] xsrc2;
        delete[] xdst;
        return;
    }
 
    const std::size_t n_ops_lt = ppred ? 
        Less::funcalls_ : UserClass::n_total_op_lt_ - last_n_op_lt;
 
    // check the algorithm correctness
    std::size_t i = 0;
    std::size_t n1 = 0;
    std::size_t n2 = 0;
    for ( ; i < ndst; i++) {
        xdst[i].origin_ <= max1_id ? n1++ : n2++;
        success = xdst[i].data_.val_ == res[i];
        if (!success)
            break;
    }
 
    // to avoid errors in --trace mode
    i = i < ndst ? i : ndst - 1;
 
    static const int cwidth = sizeof (*xdst);
 
    rw_assert (success, 0, line,
               "line %d: %s<%s, %s, %s%{?}, %s%{;}> (\"%s\", \"%s\", ...) "
               " ==> \"%{X=*.*}\", expected \"%s\"", 
               __LINE__, fname, it1name, it2name, outname, predicate, 
               funname, src1, src2, cwidth, int (ndst), i, xdst, res);
 
    // check that the operation is stable : for two equal elements
    // one from the first sequence should be taken
    success = n2 == 0;
    rw_assert (success, 0, line,
               "line %d: %s<%s, %s, %s%{?}, %s%{;}> (\"%s\", \"%s\", ...) "
               " ==> \"%{X=*.*}\" got %zu elements from first sequence and "
               "%zu from second, expected %zu from first and 0 from second",
               __LINE__, fname, it1name, it2name, outname, predicate, funname, 
               src1, src2, cwidth, int (ndst), -1, xdst, n1, n2, ndst);
 
    // check the complexity
    const std::size_t n_exp_ops =
        nsrc1 + nsrc2 > 0 ? 2 * (nsrc1 + nsrc2) - 1 : 0;
 
    rw_assert (n_ops_lt <= n_exp_ops, 0, line,
               "line %d: %s<%s, %s, %s%{?}, %s%{;}> (\"%s\", \"%s\", ...) "
               "complexity: got %zu, expected no more than %zu",
               __LINE__, fname, it1name, it2name, outname, predicate, funname, 
               src1, src2, n_ops_lt, n_exp_ops);
 
    delete[] xsrc1;
    delete[] xsrc2;
    delete[] xdst;
}
 
 
void test_set_intersection (const SetIntersectionBase &alg, 
                            bool                       predicate)
{
    const char* const it1name = alg.iter_names [0];
    const char* const it2name = alg.iter_names [1];
    const char* const outname = alg.iter_names [2];
    const char* const fname   = "set_intersection";
    const char* const funname = predicate ? "Less" : 0;
 
    rw_info (0, 0, 0,
             "%s std::%s(%s, %3$s, %s, %4$s, %1$s%{?}, %s%{;})",
             outname, fname, it1name, it2name, predicate, funname);
 
#define TEST(src1, src2, res)                                   \
    test_set_intersection (__LINE__, src1, sizeof src1 - 1,     \
                           src2, sizeof src2 - 1,               \
                           res, sizeof res - 1,                 \
                           predicate, alg)  
 
    TEST ("a", "", "");
    TEST ("abcde", "", "");
 
    TEST ("", "a", "");
    TEST ("", "abcde", "");
 
    TEST ("a", "b", "");
    TEST ("b", "a", "");
 
    TEST ("aa", "aa", "aa");
    TEST ("ab", "ab", "ab");
 
    TEST ("aa", "ab", "a");
    TEST ("ab", "bb", "b");
    TEST ("aa", "bb", "");
    TEST ("ac", "bb", "");
 
    TEST ("ace", "bdf", "");
    TEST ("acf", "bdf", "f");
    TEST ("ade", "bdf", "d");
    TEST ("bce", "bdf", "b");
 
    TEST ("aacee", "aacee", "aacee");
    TEST ("aacee", "aaace", "aace");
    TEST ("aacee", "aaaae", "aae");
    TEST ("aacee", "aaaaa", "aa");
    TEST ("aaaae", "aacee", "aae");
    TEST ("aaaaa", "aacee", "aa");
    TEST ("aacee", "aaabd", "aa");
    TEST ("aaabd", "aacee", "aa");
    TEST ("aacee", "aabee", "aaee");
}
 
 
/* extern */ int rw_opt_no_predicate;           // --no-predicate
/* extern */ int rw_opt_no_input_iter;          // --no-InputIterator
/* extern */ int rw_opt_no_output_iter;         // --no-OutputIterator
/* 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 InputIterator1, class InputIterator2, class OutputIterator>
void gen_set_intersection_test (const InputIterator1&,
                                const InputIterator2&,
                                const OutputIterator&,
                                bool predicate)
{
    const SetIntersection<InputIterator1, InputIterator2, OutputIterator> alg;
 
    test_set_intersection (alg, predicate);
}
 
 
template <class InputIterator1, class InputIterator2>
void gen_set_intersection_test (const InputIterator1 &it1,
                                const InputIterator2 &it2,
                                bool                 predicate)
{
    if (0 == rw_opt_no_output_iter)
        gen_set_intersection_test (
            it1, it2, OutputIter<UserClass>(0, 0, 0), predicate);
    if (0 == rw_opt_no_fwd_iter)
        gen_set_intersection_test (
            it1, it2, FwdIter<UserClass>(0, 0, 0), predicate);
    if (0 == rw_opt_no_bidir_iter)
        gen_set_intersection_test (
            it1, it2, BidirIter<UserClass>(0, 0, 0), predicate);
    if (0 == rw_opt_no_rnd_iter)
        gen_set_intersection_test (
            it1, it2, RandomAccessIter<UserClass>(0, 0, 0), predicate);
}
 
template <class InputIterator1>
void gen_set_intersection_test (const InputIterator1 &it1, 
                                bool                  predicate)
{
    if (0 == rw_opt_no_input_iter)
        gen_set_intersection_test (
            it1, InputIter<UserClass>(0, 0, 0), predicate);
    if (0 == rw_opt_no_fwd_iter)
        gen_set_intersection_test (
            it1, ConstFwdIter<UserClass>(0, 0, 0), predicate);
    if (0 == rw_opt_no_bidir_iter)
        gen_set_intersection_test (
            it1, ConstBidirIter<UserClass>(0, 0, 0), predicate);
    if (0 == rw_opt_no_rnd_iter)
        gen_set_intersection_test (
            it1, ConstRandomAccessIter<UserClass>(0, 0, 0), predicate);
}
 
// generates a specialization of the set_intersection test for each of 
// the required iterator categopries
static void
gen_set_intersection_test (bool predicate)
{
    rw_info (0, 0, 0,
             "template <class %s, class %s, class %s%{?}, class %s%{;}> %3$s "
             "set_intersection(%1$s, %1$s, %2$s, %2$s, %3$s%{?}, %s%{;})",
             "InputIterator1", "InputIterator2", "OutputIterator",
             predicate, "Compare", predicate, "Compare");
 
    if (rw_opt_no_output_iter)
        rw_note (0, 0, 0, "OutputIterator test disabled");
 
    if (rw_opt_no_input_iter)
        rw_note (0, 0, 0, "InputIterator test disabled");
    else
        gen_set_intersection_test (InputIter<UserClass>(0, 0, 0), predicate);
 
    if (rw_opt_no_fwd_iter)
        rw_note (0, 0, 0, "ForwardIterator test disabled");
    else
        gen_set_intersection_test (ConstFwdIter<UserClass>(0, 0, 0), predicate);
 
    if (rw_opt_no_bidir_iter)
        rw_note (0, 0, 0, "BidirectionalIterator test disabled");
    else
        gen_set_intersection_test (ConstBidirIter<UserClass>(0, 0, 0),
                                   predicate);
 
    if (rw_opt_no_rnd_iter)
        rw_note (0, 0, 0, "RandomAccessIterator test disabled");
    else
        gen_set_intersection_test (
            ConstRandomAccessIter<UserClass>(0, 0, 0), predicate);
}
 
 
static int
run_test (int, char*[])
{
    if (rw_opt_no_predicate)
        rw_note (0, 0, 0, "predicate test disabled");
 
    const int niters = rw_opt_no_predicate ? 1 : 2;
 
    for (int i = 0; i != niters; ++i) {
        gen_set_intersection_test (1 == i);
    }
 
    return 0;
}
 
 
int main (int argc, char *argv[])
{
    return rw_test (argc, argv, __FILE__,
                    "lib.set.intersection",
                    0 /* no comment */,
                    run_test,
                    "|-no-predicate#"
                    "|-no-InputIterator# "
                    "|-no-OutputIterator# "
                    "|-no-ForwardIterator# "
                    "|-no-BidirectionalIterator# "
                    "|-no-RandomAccessIterator#",
                    &rw_opt_no_predicate,
                    &rw_opt_no_input_iter,
                    &rw_opt_no_output_iter,
                    &rw_opt_no_fwd_iter,
                    &rw_opt_no_bidir_iter,
                    &rw_opt_no_rnd_iter);
}