tbx/test/tests/ring_iterator.cpp

/*!
 * \file ring_iterator.cpp
 * \brief
 *      Unit tests for ring_iterator
 *
 * \copyright Copyright (C) 2020 Christos Choutouridis <christos@choutouridis.net>
 *
 * <dl class=\"section copyright\"><dt>License</dt><dd>
 * The MIT License (MIT)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 * </dd></dl>
 *
 */
#include <core/ring_iterator.h>
#include <gtest/gtest.h>

#include <array>
#include <type_traits>

namespace Tring_iterator {
    using namespace tbx;

    // Test construction
    TEST(Tring_iterator, construct) {
        int A[10];

        //default constructor
        ring_iterator<int*, 10> i1;
        EXPECT_EQ(nullptr, i1.base());
        EXPECT_EQ(nullptr, i1.iter());
        EXPECT_EQ(10UL, i1.size());

        // implementation specific (you can remove it freely)
        EXPECT_EQ(2*sizeof(int*), sizeof(i1));

        // basic
        ring_iterator<int*, 10> i2(A);
        EXPECT_EQ(A, i2.base());
        EXPECT_EQ(A, i2.iter());
        EXPECT_EQ(10UL, i2.size());

        // basic from assignment
        ring_iterator<int*, 10> i3 = A;
        EXPECT_EQ(A, i3.base());
        EXPECT_EQ(A, i3.iter());
        EXPECT_EQ(10UL, i3.size());

        // basic with offset
        ring_iterator<int*, 10> i4(A, 5);
        EXPECT_EQ(A, i4.base());
        EXPECT_EQ(&A[5], i4.iter());
        EXPECT_EQ(10UL, i4.size());

        // copy (Legacy iterator)
        auto i5 = i2;
        EXPECT_EQ(A, i5.base());
        EXPECT_EQ(A, i5.iter());
        EXPECT_EQ(10UL, i5.size());

        // arbitrary type
        struct TT { int a,b,c; };
        std::array<TT, 10> t;
        ring_iterator<TT*, 10> it(t.data(), 2);
        EXPECT_EQ(t.begin(), it.base());
        EXPECT_EQ(&t[2], it.iter());
        EXPECT_EQ(10UL, it.size());
    }

    // Legacy iterator
    TEST(Tring_iterator, LegacyIterator) {

        EXPECT_EQ(true, (std::is_same<int, typename ring_iterator<int*, 10>::value_type>::value));
        EXPECT_EQ(true, (std::is_same<std::ptrdiff_t, typename ring_iterator<int*, 10>::difference_type>::value));
        EXPECT_EQ(true, (std::is_same<int&, typename ring_iterator<int*, 10>::reference>::value));
        EXPECT_EQ(true, (std::is_same<int*, typename ring_iterator<int*, 10>::pointer>::value));
        EXPECT_EQ(true, (std::is_same<std::random_access_iterator_tag, typename ring_iterator<int*, 10>::iterator_category>::value));

        int A[10] {0, 1, 2, 3, 4, 5, 6, 7, 8 , 9};
        ring_iterator<int*, 10> i1(A);

        // copy constructible/assignable
        auto i2 = i1;
        EXPECT_EQ(A, i2.base());
        EXPECT_EQ(A, i2.iter());
        EXPECT_EQ(10UL, i2.size());

        // dereferenceable - incrementable
        ring_iterator<int*, 10> i3(A);
        EXPECT_EQ(true, (std::is_reference<decltype(*i3)>::value));
        EXPECT_EQ(true, (std::is_same<ring_iterator<int*, 10>&, decltype(++i3)>::value));
        EXPECT_EQ(true, (std::is_reference<decltype((*i3++))>::value));

        // more practical
        ring_iterator<int*, 10> i4(A);
        ring_iterator<int*, 10> i5(A, 9);
        EXPECT_EQ(A[0], *i4);
        EXPECT_EQ(&A[1], (++i4).iter());
        // check loop
        EXPECT_EQ(A[9], *i5);
        EXPECT_EQ(&A[0], (++i5).iter());
    }

    // Legacy input iterator
    TEST(Tring_iterator, LegacyInputIterator) {
        int A[10] {0, 1, 2, 3, 4, 5, 6, 7, 8 , 9};
        ring_iterator<int*, 10> i1(A), i2(A), i3(A, 1);

        struct T { int m; };
        T B[5] { {0}, {1}, {2}, {3}, {4}};
        ring_iterator<T*, 5> it(B);

        EXPECT_EQ (true, (std::is_same<bool, decltype(i1 == i2)>::value));
        EXPECT_EQ (true, (std::is_same<bool, decltype(i1 != i2)>::value));
        EXPECT_EQ (true, (std::is_same<int&, decltype(*i1)>::value));
        EXPECT_EQ (true, (std::is_same<int, decltype(it->m)>::value));
        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>&, decltype(++i1)>::value));
        EXPECT_EQ (true, (std::is_same<int&, decltype(*i1++)>::value));

        // more practical
        EXPECT_EQ (true, i1 == i2);
        EXPECT_EQ (true, i1 != i3);
        EXPECT_EQ (0, *i1);
        EXPECT_EQ (0, it->m);
        EXPECT_EQ (true, (++i1 == i3));
        EXPECT_EQ (1, *i1++);
        EXPECT_EQ (2, *i1);
    }

    // Legacy input iterator
    TEST(Tring_iterator, LegacyOutputIterator) {
        int A[10] {0, 1, 2, 3, 4, 5, 6, 7, 8 , 9};
        ring_iterator<int*, 10> it(A);

        EXPECT_EQ (true, (std::is_assignable<decltype(*it), int>::value));
        EXPECT_EQ (true, (std::is_assignable<decltype(*it++), int>::value));

        // more practical
        *it = 42;
        EXPECT_EQ (42, A[0]);
        *it++ = 7;
        EXPECT_EQ (7, A[0]);
        EXPECT_EQ (&A[1], it.iter());
    }

    // Legacy forward iterator
    TEST(Tring_iterator, LegacyForwardIterator)
     {
        int A[10] {0, 1, 2, 3, 4, 5, 6, 7, 8 , 9};
        ring_iterator<int*, 10> it(A);

        EXPECT_EQ (0, *it++);
        EXPECT_EQ (1, *it);
    }

    // Legacy bidirectional iterator
    TEST(Tring_iterator, LegacyBidirectionalIterator) {
        int A[10] {0, 1, 2, 3, 4, 5, 6, 7, 8 , 9};
        ring_iterator<int*, 10> it(A);

        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>&, decltype(--it)>::value));
        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>, decltype(it--)>::value));
        EXPECT_EQ (true, (std::is_same<int&, decltype(*it--)>::value));

        // more practical
        ring_iterator<int*, 10> i1(A), i2(A, 9);
        EXPECT_EQ (9, *i2--);   // check loop also
        EXPECT_EQ (8, *i2);
        EXPECT_EQ (0, *i1--);   // check loop also
        EXPECT_EQ (9, *i1);
    }

    // Legacy random access iterator
    TEST(Tring_iterator, LegacyRandomAccessIterator) {
        int A[10] {0, 1, 2, 3, 4, 5, 6, 7, 8 , 9};
        ring_iterator<int*, 10> it1(A), it2(A, 7);

        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>&, decltype(it1 += 7)>::value));
        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>, decltype(it1 + 7)>::value));
        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>, decltype(7 + it1)>::value));

        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>&, decltype(it1 -= 7)>::value));
        EXPECT_EQ (true, (std::is_same<ring_iterator<int*, 10>, decltype(it1 - 7)>::value));

        EXPECT_EQ (true, (std::is_same<std::ptrdiff_t, decltype(it1 - it2)>::value));
        EXPECT_EQ (true, (std::is_same<int&, decltype(it1[7])>::value));

        EXPECT_EQ (true, (std::is_same<bool, decltype(it1 < it2)>::value));
        EXPECT_EQ (true, (std::is_same<bool, decltype(it1 > it2)>::value));
        EXPECT_EQ (true, (std::is_same<bool, decltype(it1 <= it2)>::value));
        EXPECT_EQ (true, (std::is_same<bool, decltype(it1 >= it2)>::value));

        // more practical
        ring_iterator<int*, 10> i1(A), i2(A);
        i1 += 7;
        EXPECT_EQ (7, *i1);
        i1 -= 7;
        EXPECT_EQ (0, *i1);
        i1 += 11;
        EXPECT_EQ (1, *i1);
        i1 -= 2;
        EXPECT_EQ (9, *i1);

        EXPECT_EQ (7, *(i2+7));
        EXPECT_EQ (7, *(7+i2));
        EXPECT_EQ (1, *(i2+11));
        EXPECT_EQ (1, *(11+i2));
        EXPECT_EQ (7, *(i1-2));
        EXPECT_EQ (8, *(i2-2));

        EXPECT_EQ (9, (i1 - i2));
        EXPECT_EQ (1, (i2 - i1));   // loop

    }
}