[libcxx-commits] [libcxx] [libc++] implement `std::flat_multimap` (PR #113835)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
+
+// <flat_map>
+
+// flat_multimap()
+//    noexcept(
+//        is_nothrow_default_constructible_v<key_container_type> &&
+//        is_nothrow_default_constructible_v<mapped_container_type> &&
+//        is_nothrow_default_constructible_v<key_compare>);
+
+// This tests a conforming extension
+
+#include <cassert>
+#include <flat_map>
+#include <functional>
+#include <vector>
+
+#include "test_macros.h"
+#include "MoveOnly.h"
+#include "test_allocator.h"
+
+struct ThrowingCtorComp {
+  ThrowingCtorComp() noexcept(false) {}
+  bool operator()(const auto&, const auto&) const { return false; }
+};
+
+int main(int, char**) {
+#if defined(_LIBCPP_VERSION)
+  {
+    using C = std::flat_multimap<MoveOnly, MoveOnly>;
+    static_assert(std::is_nothrow_default_constructible_v<C>);
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ldionne wrote:

Create instances of the container here and below?

https://github.com/llvm/llvm-project/pull/113835