[libc++][test] Refactor tests for ranges::swap_range algorithms (#121138)

This PR refactors tests for `ranges::swap_range`, `std::{swap_range,
iter_swap, swap}` algorithms to eliminate redundant code.

Author: winner245

libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp

@@ -10,35 +10,43 @@
 
 // template<Iterator Iter1, Iterator Iter2>
 //   requires HasSwap<Iter1::reference, Iter2::reference>
-//   void
-//   iter_swap(Iter1 a, Iter2 b);
+// void iter_swap(Iter1 a, Iter2 b); // constexpr since C++20
 
 #include <algorithm>
 #include <cassert>
 
 #include "test_macros.h"
-
-#if TEST_STD_VER > 17
-constexpr bool test_swap_constexpr()
-{
-    int i = 1;
-    int j = 2;
-    std::iter_swap(&i, &j);
-    return i == 2 && j == 1;
+#include "test_iterators.h"
+#include "type_algorithms.h"
+
+struct TestIterators {
+  template <class Iter>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    types::for_each(types::forward_iterator_list<int*>(), TestImpl<Iter>());
+  }
+
+  template <class Iter1>
+  struct TestImpl {
+    template <class Iter2>
+    TEST_CONSTEXPR_CXX20 void operator()() {
+      int i = 1;
+      int j = 2;
+      std::iter_swap(Iter1(&i), Iter2(&j));
+      assert(i == 2 && j == 1);
+    }
+  };
+};
+
+TEST_CONSTEXPR_CXX20 bool test() {
+  types::for_each(types::forward_iterator_list<int*>(), TestIterators());
+  return true;
 }
-#endif // TEST_STD_VER > 17
-
-int main(int, char**)
-{
-    int i = 1;
-    int j = 2;
-    std::iter_swap(&i, &j);
-    assert(i == 2);
-    assert(j == 1);
-
-#if TEST_STD_VER > 17
-    static_assert(test_swap_constexpr());
-#endif // TEST_STD_VER > 17
+
+int main(int, char**) {
+  test();
+#if TEST_STD_VER >= 20
+  static_assert(test());
+#endif
 
   return 0;
 }

libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/ranges.swap_ranges.pass.cpp

@@ -24,51 +24,45 @@
 #include <cassert>
 #include <ranges>
 
+#include <cstdio>
+
 #include "test_iterators.h"
+#include "type_algorithms.h"
 
 constexpr void test_different_lengths() {
-  using Expected = std::ranges::swap_ranges_result<int*, int*>;
-  int i[3] = {1, 2, 3};
-  int j[1] = {4};
+  using Expected                = std::ranges::swap_ranges_result<int*, int*>;
+  int i[3]                      = {1, 2, 3};
+  int j[1]                      = {4};
   std::same_as<Expected> auto r = std::ranges::swap_ranges(i, i + 3, j, j + 1);
   assert(r.in1 == i + 1);
   assert(r.in2 == j + 1);
-  assert(i[0] == 4);
-  assert(i[1] == 2);
-  assert(i[2] == 3);
-  assert(j[0] == 1);
+  assert(std::ranges::equal(i, std::array{4, 2, 3}));
+  assert(std::ranges::equal(j, std::array{1}));
   std::same_as<Expected> auto r2 = std::ranges::swap_ranges(i, j);
   assert(r2.in1 == i + 1);
   assert(r2.in2 == j + 1);
-  assert(i[0] == 1);
-  assert(i[1] == 2);
-  assert(i[2] == 3);
-  assert(j[0] == 4);
+  assert(std::ranges::equal(i, std::array{1, 2, 3}));
+  assert(std::ranges::equal(j, std::array{4}));
   std::same_as<Expected> auto r3 = std::ranges::swap_ranges(j, j + 1, i, i + 3);
   assert(r3.in1 == j + 1);
   assert(r3.in2 == i + 1);
-  assert(i[0] == 4);
-  assert(i[1] == 2);
-  assert(i[2] == 3);
-  assert(j[0] == 1);
+  assert(std::ranges::equal(i, std::array{4, 2, 3}));
+  assert(std::ranges::equal(j, std::array{1}));
   std::same_as<Expected> auto r4 = std::ranges::swap_ranges(j, i);
   assert(r4.in1 == j + 1);
   assert(r4.in2 == i + 1);
-  assert(i[0] == 1);
-  assert(i[1] == 2);
-  assert(i[2] == 3);
-  assert(j[0] == 4);
+  assert(std::ranges::equal(i, std::array{1, 2, 3}));
+  assert(std::ranges::equal(j, std::array{4}));
 }
 
 constexpr void test_range() {
   std::array r1 = {1, 2, 3};
   std::array r2 = {4, 5, 6};
 
-
-  std::same_as<std::ranges::in_in_result<std::array<int, 3>::iterator, std::array<int, 3>::iterator>> auto r = std::ranges::swap_ranges(r1, r2);
+  std::same_as<std::ranges::in_in_result<std::array<int, 3>::iterator, std::array<int, 3>::iterator>> auto r =
+      std::ranges::swap_ranges(r1, r2);
   assert(r.in1 == r1.end());
   assert(r.in2 == r2.end());
-
   assert((r1 == std::array{4, 5, 6}));
   assert((r2 == std::array{1, 2, 3}));
 }
@@ -78,142 +72,82 @@ constexpr void test_borrowed_input_range() {
     int r1[] = {1, 2, 3};
     int r2[] = {4, 5, 6};
     std::ranges::swap_ranges(std::views::all(r1), r2);
-    assert(r1[0] == 4);
-    assert(r1[1] == 5);
-    assert(r1[2] == 6);
-    assert(r2[0] == 1);
-    assert(r2[1] == 2);
-    assert(r2[2] == 3);
+    assert(std::ranges::equal(r1, std::array{4, 5, 6}));
+    assert(std::ranges::equal(r2, std::array{1, 2, 3}));
   }
   {
     int r1[] = {1, 2, 3};
     int r2[] = {4, 5, 6};
     std::ranges::swap_ranges(r1, std::views::all(r2));
-    assert(r1[0] == 4);
-    assert(r1[1] == 5);
-    assert(r1[2] == 6);
-    assert(r2[0] == 1);
-    assert(r2[1] == 2);
-    assert(r2[2] == 3);
+    assert(std::ranges::equal(r1, std::array{4, 5, 6}));
+    assert(std::ranges::equal(r2, std::array{1, 2, 3}));
   }
   {
     int r1[] = {1, 2, 3};
     int r2[] = {4, 5, 6};
     std::ranges::swap_ranges(std::views::all(r1), std::views::all(r2));
-    assert(r1[0] == 4);
-    assert(r1[1] == 5);
-    assert(r1[2] == 6);
-    assert(r2[0] == 1);
-    assert(r2[1] == 2);
-    assert(r2[2] == 3);
+    assert(std::ranges::equal(r1, std::array{4, 5, 6}));
+    assert(std::ranges::equal(r2, std::array{1, 2, 3}));
   }
 }
 
 constexpr void test_sentinel() {
-  int i[3] = {1, 2, 3};
-  int j[3] = {4, 5, 6};
-  using It = cpp17_input_iterator<int*>;
-  using Sent = sentinel_wrapper<It>;
-  using Expected = std::ranges::swap_ranges_result<It, It>;
-  std::same_as<Expected> auto r =
-      std::ranges::swap_ranges(It(i), Sent(It(i + 3)), It(j), Sent(It(j + 3)));
+  int i[3]                      = {1, 2, 3};
+  int j[3]                      = {4, 5, 6};
+  using It                      = cpp17_input_iterator<int*>;
+  using Sent                    = sentinel_wrapper<It>;
+  using Expected                = std::ranges::swap_ranges_result<It, It>;
+  std::same_as<Expected> auto r = std::ranges::swap_ranges(It(i), Sent(It(i + 3)), It(j), Sent(It(j + 3)));
   assert(base(r.in1) == i + 3);
   assert(base(r.in2) == j + 3);
-  assert(i[0] == 4);
-  assert(i[1] == 5);
-  assert(i[2] == 6);
-  assert(j[0] == 1);
-  assert(j[1] == 2);
-  assert(j[2] == 3);
+  assert(std::ranges::equal(i, std::array{4, 5, 6}));
+  assert(std::ranges::equal(j, std::array{1, 2, 3}));
 }
 
 template <class Iter1, class Iter2>
-constexpr void test_iterators() {
+TEST_CONSTEXPR_CXX20 void test_iterators() {
   using Expected = std::ranges::swap_ranges_result<Iter1, Iter2>;
-  int i[3] = {1, 2, 3};
-  int j[3] = {4, 5, 6};
+  int a[3]       = {1, 2, 3};
+  int b[3]       = {4, 5, 6};
   std::same_as<Expected> auto r =
-      std::ranges::swap_ranges(Iter1(i), sentinel_wrapper(Iter1(i + 3)), Iter2(j), sentinel_wrapper(Iter2(j + 3)));
-  assert(base(r.in1) == i + 3);
-  assert(base(r.in2) == j + 3);
-  assert(i[0] == 4);
-  assert(i[1] == 5);
-  assert(i[2] == 6);
-  assert(j[0] == 1);
-  assert(j[1] == 2);
-  assert(j[2] == 3);
+      std::ranges::swap_ranges(Iter1(a), sentinel_wrapper(Iter1(a + 3)), Iter2(b), sentinel_wrapper(Iter2(b + 3)));
+  assert(base(r.in1) == a + 3);
+  assert(base(r.in2) == b + 3);
+  assert(std::ranges::equal(a, std::array{4, 5, 6}));
+  assert(std::ranges::equal(b, std::array{1, 2, 3}));
 }
 
 constexpr void test_rval_range() {
   {
-    using Expected = std::ranges::swap_ranges_result<std::array<int, 3>::iterator, std::ranges::dangling>;
+    using Expected       = std::ranges::swap_ranges_result<std::array<int, 3>::iterator, std::ranges::dangling>;
     std::array<int, 3> r = {1, 2, 3};
     std::same_as<Expected> auto a = std::ranges::swap_ranges(r, std::array{4, 5, 6});
     assert((r == std::array{4, 5, 6}));
     assert(a.in1 == r.begin() + 3);
   }
   {
     std::array<int, 3> r = {1, 2, 3};
-    using Expected = std::ranges::swap_ranges_result<std::ranges::dangling, std::array<int, 3>::iterator>;
+    using Expected       = std::ranges::swap_ranges_result<std::ranges::dangling, std::array<int, 3>::iterator>;
     std::same_as<Expected> auto b = std::ranges::swap_ranges(std::array{4, 5, 6}, r);
     assert((r == std::array{4, 5, 6}));
     assert(b.in2 == r.begin() + 3);
   }
 }
 
-template <class Out>
-constexpr void test_proxy_in_iterators() {
-  test_iterators<ProxyIterator<cpp20_input_iterator<int*>>, Out>();
-  test_iterators<ProxyIterator<forward_iterator<int*>>, Out>();
-  test_iterators<ProxyIterator<bidirectional_iterator<int*>>, Out>();
-  test_iterators<ProxyIterator<random_access_iterator<int*>>, Out>();
-  test_iterators<ProxyIterator<contiguous_iterator<int*>>, Out>();
-}
-
 constexpr bool test() {
   test_range();
-
-  test_iterators<cpp20_input_iterator<int*>, cpp20_input_iterator<int*>>();
-  test_iterators<cpp20_input_iterator<int*>, forward_iterator<int*>>();
-  test_iterators<cpp20_input_iterator<int*>, bidirectional_iterator<int*>>();
-  test_iterators<cpp20_input_iterator<int*>, random_access_iterator<int*>>();
-  test_iterators<cpp20_input_iterator<int*>, int*>();
-
-  test_iterators<forward_iterator<int*>, cpp20_input_iterator<int*>>();
-  test_iterators<forward_iterator<int*>, forward_iterator<int*>>();
-  test_iterators<forward_iterator<int*>, bidirectional_iterator<int*>>();
-  test_iterators<forward_iterator<int*>, random_access_iterator<int*>>();
-  test_iterators<forward_iterator<int*>, int*>();
-
-  test_iterators<bidirectional_iterator<int*>, cpp20_input_iterator<int*>>();
-  test_iterators<bidirectional_iterator<int*>, forward_iterator<int*>>();
-  test_iterators<bidirectional_iterator<int*>, bidirectional_iterator<int*>>();
-  test_iterators<bidirectional_iterator<int*>, random_access_iterator<int*>>();
-  test_iterators<bidirectional_iterator<int*>, int*>();
-
-  test_iterators<random_access_iterator<int*>, cpp20_input_iterator<int*>>();
-  test_iterators<random_access_iterator<int*>, forward_iterator<int*>>();
-  test_iterators<random_access_iterator<int*>, bidirectional_iterator<int*>>();
-  test_iterators<random_access_iterator<int*>, random_access_iterator<int*>>();
-  test_iterators<random_access_iterator<int*>, int*>();
-
-  test_iterators<int*, cpp20_input_iterator<int*>>();
-  test_iterators<int*, forward_iterator<int*>>();
-  test_iterators<int*, bidirectional_iterator<int*>>();
-  test_iterators<int*, random_access_iterator<int*>>();
-  test_iterators<int*, int*>();
-
-  test_proxy_in_iterators<ProxyIterator<cpp20_input_iterator<int*>>>();
-  test_proxy_in_iterators<ProxyIterator<forward_iterator<int*>>>();
-  test_proxy_in_iterators<ProxyIterator<bidirectional_iterator<int*>>>();
-  test_proxy_in_iterators<ProxyIterator<random_access_iterator<int*>>>();
-  test_proxy_in_iterators<ProxyIterator<contiguous_iterator<int*>>>();
-
   test_sentinel();
   test_different_lengths();
   test_borrowed_input_range();
   test_rval_range();
 
+  types::for_each(types::cpp20_input_iterator_list<int*>(), []<class Iter1>() {
+    types::for_each(types::cpp20_input_iterator_list<int*>(), []<class Iter2>() {
+      test_iterators<Iter1, Iter2>();
+      test_iterators<ProxyIterator<Iter1>, ProxyIterator<Iter2>>();
+    });
+  });
+
   return true;
 }