[libcxx-commits] [libcxx] [libc++] implement std::flat_set (PR #125241)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,94 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+// UNSUPPORTED: availability-pmr-missing
+
+// <flat_set>
+
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <deque>
+#include <initializer_list>
+#include <list>
+#include <flat_set>
+#include <functional>
+#include <memory_resource>
+#include <ranges>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include "test_allocator.h"
+
+using P  = std::pair<int, long>;
+using PC = std::pair<const int, long>;
+
+void test_containers() {
+  std::deque<int, test_allocator<int>> ks({1, 2, 1, INT_MAX, 3}, test_allocator<int>(0, 42));
+  std::deque<int, test_allocator<int>> sorted_ks({1, 2, 3, INT_MAX}, test_allocator<int>(0, 42));
+  const int expected[] = {1, 2, 3, INT_MAX};
+  {
+    std::pmr::monotonic_buffer_resource mr;
+    std::pmr::monotonic_buffer_resource mr2;
+    std::pmr::deque<int> pks(ks.begin(), ks.end(), &mr);
+    std::flat_set s(std::move(pks), &mr2);
+
+    ASSERT_SAME_TYPE(decltype(s), std::flat_set<int, std::less<int>, std::pmr::deque<int>>);
+    assert(std::ranges::equal(s, expected));
+    auto keys = std::move(s).extract();
+    assert(keys.get_allocator().resource() == &mr2);
+  }
+  {
+    std::pmr::monotonic_buffer_resource mr;
+    std::pmr::monotonic_buffer_resource mr2;
+    std::pmr::deque<int> pks(sorted_ks.begin(), sorted_ks.end(), &mr);
+    std::flat_set s(std::sorted_unique, std::move(pks), &mr2);
+
+    ASSERT_SAME_TYPE(decltype(s), std::flat_set<int, std::less<int>, std::pmr::deque<int>>);
+    assert(std::ranges::equal(s, expected));
+    auto keys = std::move(s).extract();
+    assert(keys.get_allocator().resource() == &mr2);
+  }
+}
+
+void test_containers_compare() {
+  std::deque<int, test_allocator<int>> ks({1, 2, 1, INT_MAX, 3}, test_allocator<int>(0, 42));
+  std::deque<int, test_allocator<int>> sorted_ks({INT_MAX, 3, 2, 1}, test_allocator<int>(0, 42));
+  const int expected[] = {INT_MAX, 3, 2, 1};
+  {
+    std::pmr::monotonic_buffer_resource mr;
+    std::pmr::monotonic_buffer_resource mr2;
+    std::pmr::deque<int> pks(ks.begin(), ks.end(), &mr);
+    std::flat_set s(std::move(pks), std::greater<int>(), &mr2);
+
+    ASSERT_SAME_TYPE(decltype(s), std::flat_set<int, std::greater<int>, std::pmr::deque<int>>);
+    assert(std::ranges::equal(s, expected));
+    auto keys = std::move(s).extract();
+    assert(keys.get_allocator().resource() == &mr2);
+  }
+  {
+    std::pmr::monotonic_buffer_resource mr;
+    std::pmr::monotonic_buffer_resource mr2;
+    std::pmr::deque<int> pks(sorted_ks.begin(), sorted_ks.end(), &mr);
+    std::flat_set s(std::sorted_unique, std::move(pks), std::greater<int>(), &mr2);
+
+    ASSERT_SAME_TYPE(decltype(s), std::flat_set<int, std::greater<int>, std::pmr::deque<int>>);
+    assert(std::ranges::equal(s, expected));
+    auto keys = std::move(s).extract();
+    assert(keys.get_allocator().resource() == &mr2);
+  }
+}
+
+int main(int, char**) {
+  test_containers();
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ldionne wrote:

Same comment as for deduction guides above.

https://github.com/llvm/llvm-project/pull/125241