[libc++][test] Refactor tests for ranges::swap_range algorithms

[winner245]

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

[github-actions]

✅ With the latest revision this PR passed the C/C++ code formatter.

[llvmbot]

@llvm/pr-subscribers-libcxx

Author: Peng Liu (winner245)

Changes

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

---

Full diff: https://github.com/llvm/llvm-project/pull/121138.diff

3 Files Affected:

• (modified) libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp (+26-17)
• (modified) libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/ranges.swap_ranges.pass.cpp (+69-117)
• (modified) libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp (+89-142)

diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp
index b3a9f5fc259ef7..72485b9d7e5eb7 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/iter_swap.pass.cpp
@@ -17,28 +17,37 @@
 #include <cassert>
 
 #include "test_macros.h"
+#include "test_iterators.h"
+#include "type_algorithms.h"
 
-#if TEST_STD_VER > 17
-constexpr bool test_swap_constexpr()
-{
+template <class Iter1>
+struct Test {
+  template <class Iter2>
+  TEST_CONSTEXPR_CXX20 void operator()() {
     int i = 1;
     int j = 2;
-    std::iter_swap(&i, &j);
-    return i == 2 && j == 1;
+    std::iter_swap(Iter1(&i), Iter2(&j));
+    assert(i == 2 && j == 1);
+  }
+};
+
+struct TestIterators {
+  template <class Iter>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    types::for_each(types::forward_iterator_list<int*>(), Test<Iter>());
+  }
+};
+
+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;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/ranges.swap_ranges.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/ranges.swap_ranges.pass.cpp
index a8d69b2832b462..aec0d6ad1c0e16 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/ranges.swap_ranges.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/ranges.swap_ranges.pass.cpp
@@ -25,50 +25,42 @@
 #include <ranges>
 
 #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}));
 }
@@ -78,75 +70,79 @@ 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() {
-  using Expected = std::ranges::swap_ranges_result<Iter1, Iter2>;
-  int i[3] = {1, 2, 3};
-  int j[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);
-}
+template <class Iter1>
+struct Test {
+  template <class Iter2>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    using Expected = std::ranges::swap_ranges_result<Iter1, Iter2>;
+    int a[3]       = {1, 2, 3};
+    int b[3]       = {4, 5, 6};
+    std::same_as<Expected> auto r =
+        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}));
+  }
+};
+
+struct TestIterators {
+  template <class Iter>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    types::for_each(types::cpp20_input_iterator_list<int*>(), Test<Iter>());
+  }
+};
+
+template <class Ptr>
+using cpp20_proxy_in_iterator_list =
+    types::type_list<Cpp20InputProxyIterator<Ptr>,
+                     ForwardProxyIterator<Ptr>,
+                     BidirectionalProxyIterator<Ptr>,
+                     RandomAccessProxyIterator<Ptr>,
+                     ContiguousProxyIterator<Ptr>>;
+
+struct TestProxyInIterators {
+  template <class Iter>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    types::for_each(cpp20_proxy_in_iterator_list<int*>(), Test<Iter>());
+  }
+};
 
 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}));
@@ -154,65 +150,21 @@ constexpr void test_rval_range() {
   }
   {
     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*>(), TestIterators());
+  types::for_each(cpp20_proxy_in_iterator_list<int*>(), TestProxyInIterators());
 
   return true;
 }
diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
index 8bfbcd755e39f7..09374b9a64bf11 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.swap/swap_ranges.pass.cpp
@@ -14,162 +14,109 @@
 //   swap_ranges(Iter1 first1, Iter1 last1, Iter2 first2);
 
 #include <algorithm>
+#include <array>
 #include <cassert>
 #include <memory>
 #include <utility>
 
 #include "test_macros.h"
 #include "test_iterators.h"
-
-template<class Iter1, class Iter2>
-void
-test()
-{
-    int i[3] = {1, 2, 3};
-    int j[3] = {4, 5, 6};
-    Iter2 r = std::swap_ranges(Iter1(i), Iter1(i+3), Iter2(j));
-    assert(base(r) == 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);
+#include "type_algorithms.h"
+
+template <class Iter1>
+struct Test1 {
+  template <class Iter2>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    int a[] = {1, 2, 3};
+    int b[] = {4, 5, 6};
+    Iter2 r = std::swap_ranges(Iter1(a), Iter1(a + 3), Iter2(b));
+    assert(base(r) == b + 3);
+    assert(a[0] == 4 && a[1] == 5 && a[2] == 6);
+    assert(b[0] == 1 && b[1] == 2 && b[2] == 3);
+  }
+};
+
+struct TestPtr {
+  template <class Iter>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    types::for_each(types::forward_iterator_list<int*>(), Test1<Iter>());
+  }
+};
+
+TEST_CONSTEXPR_CXX20 bool test_ptr() {
+  types::for_each(types::forward_iterator_list<int*>(), TestPtr());
+  return true;
 }
 
 #if TEST_STD_VER >= 11
-template<class Iter1, class Iter2>
-void
-test1()
-{
-    std::unique_ptr<int> i[3];
+template <class Iter1>
+struct Test2 {
+  template <class Iter2>
+  TEST_CONSTEXPR_CXX23 void operator()() {
+    std::unique_ptr<int> a[3];
     for (int k = 0; k < 3; ++k)
-        i[k].reset(new int(k+1));
-    std::unique_ptr<int> j[3];
+      a[k].reset(new int(k + 1));
+    std::unique_ptr<int> b[3];
     for (int k = 0; k < 3; ++k)
-        j[k].reset(new int(k+4));
-    Iter2 r = std::swap_ranges(Iter1(i), Iter1(i+3), Iter2(j));
-    assert(base(r) == 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);
+      b[k].reset(new int(k + 4));
+    Iter2 r = std::swap_ranges(Iter1(a), Iter1(a + 3), Iter2(b));
+    assert(base(r) == b + 3);
+    assert(*a[0] == 4 && *a[1] == 5 && *a[2] == 6);
+    assert(*b[0] == 1 && *b[1] == 2 && *b[2] == 3);
+  }
+};
+
+struct TestUnqPtr {
+  template <class Iter>
+  TEST_CONSTEXPR_CXX20 void operator()() {
+    types::for_each(types::forward_iterator_list<std::unique_ptr<int>*>(), Test2<Iter>());
+  }
+};
+
+TEST_CONSTEXPR_CXX23 bool test_unq_ptr() {
+  types::for_each(types::forward_iterator_list<std::unique_ptr<int>*>(), TestUnqPtr());
+  return true;
 }
-#endif // TEST_STD_VER >= 11
-
-void test2()
-{
-    {
-    int src[2][2]      = {{0, 1}, {2, 3}};
-    decltype(src) dest = {{9, 8}, {7, 6}};
-
-    std::swap(src, dest);
-
-    assert ( src[0][0] == 9 );
-    assert ( src[0][1] == 8 );
-    assert ( src[1][0] == 7 );
-    assert ( src[1][1] == 6 );
-
-    assert ( dest[0][0] == 0 );
-    assert ( dest[0][1] == 1 );
-    assert ( dest[1][0] == 2 );
-    assert ( dest[1][1] == 3 );
-    }
-
-    {
-    int src[3][3]      = {{0, 1, 2}, {3, 4, 5}, {6, 7, 8}};
-    decltype(src) dest = {{9, 8, 7}, {6, 5, 4}, {3, 2, 1}};
-
-    std::swap(src, dest);
-
-    assert ( src[0][0] == 9 );
-    assert ( src[0][1] == 8 );
-    assert ( src[0][2] == 7 );
-    assert ( src[1][0] == 6 );
-    assert ( src[1][1] == 5 );
-    assert ( src[1][2] == 4 );
-    assert ( src[2][0] == 3 );
-    assert ( src[2][1] == 2 );
-    assert ( src[2][2] == 1 );
-
-    assert ( dest[0][0] == 0 );
-    assert ( dest[0][1] == 1 );
-    assert ( dest[0][2] == 2 );
-    assert ( dest[1][0] == 3 );
-    assert ( dest[1][1] == 4 );
-    assert ( dest[1][2] == 5 );
-    assert ( dest[2][0] == 6 );
-    assert ( dest[2][1] == 7 );
-    assert ( dest[2][2] == 8 );
-    }
-}
-
-#if TEST_STD_VER > 17
-constexpr bool test_swap_constexpr()
-{
-    int i[3] = {1, 2, 3};
-    int j[3] = {4, 5, 6};
-    std::swap_ranges(i, i+3, j);
-    return i[0] == 4 &&
-           i[1] == 5 &&
-           i[2] == 6 &&
-           j[0] == 1 &&
-           j[1] == 2 &&
-           j[2] == 3;
+#endif
+
+TEST_CONSTEXPR_CXX20 bool test_simple_cases() {
+  {
+    std::array<int, 3> a = {1, 2, 3}, a0 = a;
+    std::array<int, 3> b = {4, 5, 6}, b0 = b;
+    std::swap_ranges(a.begin(), a.end(), b.begin());
+    assert(a == b0);
+    assert(b == a0);
+  }
+  {
+    std::array<std::array<int, 2>, 2> a = {{{0, 1}, {2, 3}}}, a0 = a;
+    std::array<std::array<int, 2>, 2> b = {{{9, 8}, {7, 6}}}, b0 = b;
+    std::swap(a, b);
+    assert(a == b0);
+    assert(b == a0);
+  }
+  {
+    std::array<std::array<int, 3>, 3> a = {{{0, 1, 2}, {3, 4, 5}, {6, 7, 8}}}, a0 = a;
+    std::array<std::array<int, 3>, 3> b = {{{9, 8, 7}, {6, 5, 4}, {3, 2, 1}}}, b0 = b;
+    std::swap(a, b);
+    assert(a == b0);
+    assert(b == a0);
+  }
+
+  return true;
 }
-#endif // TEST_STD_VER > 17
-
-int main(int, char**)
-{
-    test<forward_iterator<int*>, forward_iterator<int*> >();
-    test<forward_iterator<int*>, bidirectional_iterator<int*> >();
-    test<forward_iterator<int*>, random_access_iterator<int*> >();
-    test<forward_iterator<int*>, int*>();
-
-    test<bidirectional_iterator<int*>, forward_iterator<int*> >();
-    test<bidirectional_iterator<int*>, bidirectional_iterator<int*> >();
-    test<bidirectional_iterator<int*>, random_access_iterator<int*> >();
-    test<bidirectional_iterator<int*>, int*>();
-
-    test<random_access_iterator<int*>, forward_iterator<int*> >();
-    test<random_access_iterator<int*>, bidirectional_iterator<int*> >();
-    test<random_access_iterator<int*>, random_access_iterator<int*> >();
-    test<random_access_iterator<int*>, int*>();
-
-    test<int*, forward_iterator<int*> >();
-    test<int*, bidirectional_iterator<int*> >();
-    test<int*, random_access_iterator<int*> >();
-    test<int*, int*>();
 
+int main(int, char**) {
+  test_simple_cases();
+  test_ptr();
 #if TEST_STD_VER >= 11
-    test1<forward_iterator<std::unique_ptr<int>*>, forward_iterator<std::unique_ptr<int>*> >();
-    test1<forward_iterator<std::unique_ptr<int>*>, bidirectional_iterator<std::unique_ptr<int>*> >();
-    test1<forward_iterator<std::unique_ptr<int>*>, random_access_iterator<std::unique_ptr<int>*> >();
-    test1<forward_iterator<std::unique_ptr<int>*>, std::unique_ptr<int>*>();
-
-    test1<bidirectional_iterator<std::unique_ptr<int>*>, forward_iterator<std::unique_ptr<int>*> >();
-    test1<bidirectional_iterator<std::unique_ptr<int>*>, bidirectional_iterator<std::unique_ptr<int>*> >();
-    test1<bidirectional_iterator<std::unique_ptr<int>*>, random_access_iterator<std::unique_ptr<int>*> >();
-    test1<bidirectional_iterator<std::unique_ptr<int>*>, std::unique_ptr<int>*>();
-
-    test1<random_access_iterator<std::unique_ptr<int>*>, forward_iterator<std::unique_ptr<int>*> >();
-    test1<random_access_iterator<std::unique_ptr<int>*>, bidirectional_iterator<std::unique_ptr<int>*> >();
-    test1<random_access_iterator<std::unique_ptr<int>*>, random_access_iterator<std::unique_ptr<int>*> >();
-    test1<random_access_iterator<std::unique_ptr<int>*>, std::unique_ptr<int>*>();
-
-    test1<std::unique_ptr<int>*, forward_iterator<std::unique_ptr<int>*> >();
-    test1<std::unique_ptr<int>*, bidirectional_iterator<std::unique_ptr<int>*> >();
-    test1<std::unique_ptr<int>*, random_access_iterator<std::unique_ptr<int>*> >();
-    test1<std::unique_ptr<int>*, std::unique_ptr<int>*>();
-#endif // TEST_STD_VER >= 11
-
-#if TEST_STD_VER > 17
-    static_assert(test_swap_constexpr());
-#endif // TEST_STD_VER > 17
-
-    test2();
-
+  test_unq_ptr();
+#endif
+#if TEST_STD_VER >= 20
+  static_assert(test_simple_cases());
+  static_assert(test_ptr());
+#endif
+#if TEST_STD_VER >= 23
+  static_assert(test_unq_ptr());
+#endif
   return 0;
 }

[ldionne]

Thanks a lot for the improvements, I do have some comments before we merge this but it generally looks really good.

[ldionne]

LGTM with minor comments. Thanks a lot for the improved test coverage, that is awesome!

[ldionne]

Thanks a lot for the refactoring!

[ldionne]

This is fine since it's a pre-existing issue, but as a simple follow-up we should add coverage for sequences of more than 3 elements.