Fix bug 20740 - std::set/std::map don't support heterogeneous lookup for count(). Thanks to Jim Porter for the bug report

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@216353 91177308-0d34-0410-b5e6-96231b3b80d8

test/containers/associative/set/count.pass.cpp

@@ -17,6 +17,7 @@
 #include <cassert>
 
 #include "min_allocator.h"
+#include "private_constructor.hpp"
 
 int main()
 {
@@ -92,4 +93,76 @@ int main()
         assert(r == 0);
     }
 #endif
+#if _LIBCPP_STD_VER > 11
+    {
+        typedef int V;
+        typedef std::set<int, std::less<>> M;
+        typedef M::size_type R;
+        V ar[] =
+        {
+            5,
+            6,
+            7,
+            8,
+            9,
+            10,
+            11,
+            12
+        };
+        const M m(ar, ar+sizeof(ar)/sizeof(ar[0]));
+        R r = m.count(5);
+        assert(r == 1);
+        r = m.count(6);
+        assert(r == 1);
+        r = m.count(7);
+        assert(r == 1);
+        r = m.count(8);
+        assert(r == 1);
+        r = m.count(9);
+        assert(r == 1);
+        r = m.count(10);
+        assert(r == 1);
+        r = m.count(11);
+        assert(r == 1);
+        r = m.count(12);
+        assert(r == 1);
+        r = m.count(4);
+        assert(r == 0);
+    }
+    {
+    typedef PrivateConstructor V;
+    typedef std::set<V, std::less<>> M;
+        typedef M::size_type R;
+
+    M m;
+    m.insert ( V::make ( 5 ));
+    m.insert ( V::make ( 6 ));
+    m.insert ( V::make ( 7 ));
+    m.insert ( V::make ( 8 ));
+    m.insert ( V::make ( 9 ));
+    m.insert ( V::make ( 10 ));
+    m.insert ( V::make ( 11 ));
+    m.insert ( V::make ( 12 ));
+
+    R r = m.count(5);
+    assert(r == 1);
+    r = m.count(6);
+    assert(r == 1);
+    r = m.count(7);
+    assert(r == 1);
+    r = m.count(8);
+    assert(r == 1);
+    r = m.count(9);
+    assert(r == 1);
+    r = m.count(10);
+    assert(r == 1);
+    r = m.count(11);
+    assert(r == 1);
+    r = m.count(12);
+    assert(r == 1);
+    r = m.count(4);
+    assert(r == 0);
+    }
+#endif
+
 }