[libc++][P0202] Marked algorithms copy/copy_n/copy_if/copy_backward constexpr

Thanks to Michael Park for the patch.

Differential Revision: https://reviews.llvm.org/D68837

1 files changed, 44 insertions, 48 deletions

diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp
index 9dcace7a03d..cc99859d8a7 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.copy/copy.pass.cpp
@@ -18,21 +18,9 @@
 #include "test_macros.h"
 #include "test_iterators.h"
 
-// #if TEST_STD_VER > 17
-// TEST_CONSTEXPR bool test_constexpr() {
-//     int ia[] = {1, 2, 3, 4, 5};
-//     int ic[] = {6, 6, 6, 6, 6, 6, 6};
-//
-//     auto p = std::copy(std::begin(ia), std::end(ia), std::begin(ic));
-//     return std::equal(std::begin(ia), std::end(ia), std::begin(ic), p)
-//         && std::all_of(p, std::end(ic), [](int a){return a == 6;})
-//         ;
-//     }
-// #endif
-
 template <class InIter, class OutIter>
-void
-test()
+TEST_CONSTEXPR_CXX20 void
+test_copy()
 {
     const unsigned N = 1000;
     int ia[N];
@@ -46,46 +34,54 @@ test()
         assert(ia[i] == ib[i]);
 }
 
-int main(int, char**)
+TEST_CONSTEXPR_CXX20 bool
+test()
 {
-    test<input_iterator<const int*>, output_iterator<int*> >();
-    test<input_iterator<const int*>, input_iterator<int*> >();
-    test<input_iterator<const int*>, forward_iterator<int*> >();
-    test<input_iterator<const int*>, bidirectional_iterator<int*> >();
-    test<input_iterator<const int*>, random_access_iterator<int*> >();
-    test<input_iterator<const int*>, int*>();
+    test_copy<input_iterator<const int*>, output_iterator<int*> >();
+    test_copy<input_iterator<const int*>, input_iterator<int*> >();
+    test_copy<input_iterator<const int*>, forward_iterator<int*> >();
+    test_copy<input_iterator<const int*>, bidirectional_iterator<int*> >();
+    test_copy<input_iterator<const int*>, random_access_iterator<int*> >();
+    test_copy<input_iterator<const int*>, int*>();
 
-    test<forward_iterator<const int*>, output_iterator<int*> >();
-    test<forward_iterator<const int*>, input_iterator<int*> >();
-    test<forward_iterator<const int*>, forward_iterator<int*> >();
-    test<forward_iterator<const int*>, bidirectional_iterator<int*> >();
-    test<forward_iterator<const int*>, random_access_iterator<int*> >();
-    test<forward_iterator<const int*>, int*>();
+    test_copy<forward_iterator<const int*>, output_iterator<int*> >();
+    test_copy<forward_iterator<const int*>, input_iterator<int*> >();
+    test_copy<forward_iterator<const int*>, forward_iterator<int*> >();
+    test_copy<forward_iterator<const int*>, bidirectional_iterator<int*> >();
+    test_copy<forward_iterator<const int*>, random_access_iterator<int*> >();
+    test_copy<forward_iterator<const int*>, int*>();
 
-    test<bidirectional_iterator<const int*>, output_iterator<int*> >();
-    test<bidirectional_iterator<const int*>, input_iterator<int*> >();
-    test<bidirectional_iterator<const int*>, forward_iterator<int*> >();
-    test<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
-    test<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
-    test<bidirectional_iterator<const int*>, int*>();
+    test_copy<bidirectional_iterator<const int*>, output_iterator<int*> >();
+    test_copy<bidirectional_iterator<const int*>, input_iterator<int*> >();
+    test_copy<bidirectional_iterator<const int*>, forward_iterator<int*> >();
+    test_copy<bidirectional_iterator<const int*>, bidirectional_iterator<int*> >();
+    test_copy<bidirectional_iterator<const int*>, random_access_iterator<int*> >();
+    test_copy<bidirectional_iterator<const int*>, int*>();
 
-    test<random_access_iterator<const int*>, output_iterator<int*> >();
-    test<random_access_iterator<const int*>, input_iterator<int*> >();
-    test<random_access_iterator<const int*>, forward_iterator<int*> >();
-    test<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
-    test<random_access_iterator<const int*>, random_access_iterator<int*> >();
-    test<random_access_iterator<const int*>, int*>();
+    test_copy<random_access_iterator<const int*>, output_iterator<int*> >();
+    test_copy<random_access_iterator<const int*>, input_iterator<int*> >();
+    test_copy<random_access_iterator<const int*>, forward_iterator<int*> >();
+    test_copy<random_access_iterator<const int*>, bidirectional_iterator<int*> >();
+    test_copy<random_access_iterator<const int*>, random_access_iterator<int*> >();
+    test_copy<random_access_iterator<const int*>, int*>();
 
-    test<const int*, output_iterator<int*> >();
-    test<const int*, input_iterator<int*> >();
-    test<const int*, forward_iterator<int*> >();
-    test<const int*, bidirectional_iterator<int*> >();
-    test<const int*, random_access_iterator<int*> >();
-    test<const int*, int*>();
+    test_copy<const int*, output_iterator<int*> >();
+    test_copy<const int*, input_iterator<int*> >();
+    test_copy<const int*, forward_iterator<int*> >();
+    test_copy<const int*, bidirectional_iterator<int*> >();
+    test_copy<const int*, random_access_iterator<int*> >();
+    test_copy<const int*, int*>();
+
+  return true;
+}
+
+int main(int, char**)
+{
+    test();
 
-// #if TEST_STD_VER > 17
-//     static_assert(test_constexpr());
-// #endif
+#if TEST_STD_VER > 17
+    static_assert(test());
+#endif
 
   return 0;
 }