First half of C++17's splicing maps and sets

This commit adds a node handle type, (located in __node_handle), and adds
extract() and insert() members to all map and set types, as well as their
implementations in __tree and __hash_table.

The second half of this feature is adding merge() members, which splice nodes
in bulk from one container into another. This will be committed in a follow-up.

Differential revision: https://reviews.llvm.org/D46845

llvm-svn: 338472

1 files changed, 60 insertions, 0 deletions

diff --git a/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp b/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp
new file mode 100644
index 00000000000..0f41169e9fe
--- /dev/null
+++ b/libcxx/test/std/containers/associative/multiset/extract_iterator.pass.cpp
@@ -0,0 +1,60 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <set>
+
+// class multiset
+
+// node_type extract(const_iterator);
+
+#include <set>
+#include "min_allocator.h"
+#include "Counter.h"
+
+template <class Container>
+void test(Container& c)
+{
+    size_t sz = c.size();
+
+    for (auto first = c.cbegin(); first != c.cend();)
+    {
+        auto key_value = *first;
+        typename Container::node_type t = c.extract(first++);
+        --sz;
+        assert(t.value() == key_value);
+        assert(t.get_allocator() == c.get_allocator());
+        assert(sz == c.size());
+    }
+
+    assert(c.size() == 0);
+}
+
+int main()
+{
+    {
+        using set_type = std::multiset<int>;
+        set_type m = {1, 2, 3, 4, 5, 6};
+        test(m);
+    }
+
+    {
+        std::multiset<Counter<int>> m = {1, 2, 3, 4, 5, 6};
+        assert(Counter_base::gConstructed == 6);
+        test(m);
+        assert(Counter_base::gConstructed == 0);
+    }
+
+    {
+        using min_alloc_set = std::multiset<int, std::less<int>, min_allocator<int>>;
+        min_alloc_set m = {1, 2, 3, 4, 5, 6};
+        test(m);
+    }
+}