Another batch of P0202 constepr algirithms. remove/remove_if/remove_copy/remove_copy_if/reverse_copy, and tests (commented out) for rotate_copy, because that depends on std::copy

llvm-svn: 323152

1 files changed, 20 insertions, 1 deletions

diff --git a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp
index bf5f79cf835..ae7b3418426 100644
--- a/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp
+++ b/libcxx/test/std/algorithms/alg.modifying.operations/alg.remove/remove_copy.pass.cpp
@@ -11,14 +11,29 @@
 
 // template<InputIterator InIter, OutputIterator<auto, InIter::reference> OutIter, class T>
 //   requires HasEqualTo<InIter::value_type, T>
-//   OutIter
+//   constexpr OutIter         // constexpr after C++17
 //   remove_copy(InIter first, InIter last, OutIter result, const T& value);
 
 #include <algorithm>
 #include <cassert>
 
+#include "test_macros.h"
 #include "test_iterators.h"
 
+#if TEST_STD_VER > 17
+TEST_CONSTEXPR bool test_constexpr() {
+    int ia[] = {1, 3, 5, 2, 5, 6};
+    int ib[std::size(ia)] = {0};
+    
+    auto it = std::remove_copy(std::begin(ia), std::end(ia), std::begin(ib), 5);
+
+    return std::distance(std::begin(ib), it) == (std::size(ia) - 2)   // we removed two elements
+        && std::none_of(std::begin(ib), it, [](int a) {return a == 5;})
+        && std::all_of (it, std::end(ib),   [](int a) {return a == 0;})
+           ;
+    }
+#endif
+
 template <class InIter, class OutIter>
 void
 test()
@@ -67,4 +82,8 @@ int main()
     test<const int*, bidirectional_iterator<int*> >();
     test<const int*, random_access_iterator<int*> >();
     test<const int*, int*>();
+
+#if TEST_STD_VER > 17
+    static_assert(test_constexpr());
+#endif
 }