diff -r 7bcea73303ce -r b3baaf9b7e3c test/test_list.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/test_list.cpp	Sat Apr 16 18:02:10 2022 +0200
@@ -0,0 +1,827 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "cx/linked_list.h"
+#include "cx/utils.h"
+#include "util_allocator.h"
+
+#include <gtest/gtest.h>
+#include <array>
+#include <vector>
+#include <unordered_set>
+#include <algorithm>
+
+static int cmp_int_impl(
+        int const *l,
+        int const *r
+) {
+    int left = *l, right = *r;
+    return left == right ? 0 : (left < right ? -1 : 1);
+}
+
+#define cmp_int ((CxListComparator) cmp_int_impl)
+
+struct node {
+    node *next = nullptr;
+    node *prev = nullptr;
+    int data = 0;
+};
+
+const ptrdiff_t loc_prev = offsetof(struct node, prev);
+const ptrdiff_t loc_next = offsetof(struct node, next);
+const ptrdiff_t loc_data = offsetof(struct node, data);
+
+struct node_test_data {
+    node *begin;
+
+    explicit node_test_data(node *begin) : begin(begin) {}
+    node_test_data(node_test_data&) = delete;
+    node_test_data(node_test_data&&) = default;
+
+    ~node_test_data() {
+        auto n = begin;
+        while (n != nullptr) {
+            auto next = n->next;
+            delete n;
+            n = next;
+        }
+    }
+};
+
+static node_test_data create_nodes_test_data(size_t len) {
+    if (len == 0) return node_test_data{nullptr};
+    auto begin = new node;
+    auto prev = begin;
+    for (size_t i = 1; i < len; i++) {
+        auto n = new node;
+        cx_linked_list_link(prev, n, loc_prev, loc_next);
+        prev = n;
+    }
+    return node_test_data{begin};
+}
+
+template<typename InputIter>
+static node_test_data create_nodes_test_data(InputIter begin, InputIter end) {
+    if (begin == end) return node_test_data{nullptr};
+    node *first = new node;
+    first->data = *begin;
+    node *prev = first;
+    begin++;
+    for (; begin != end; begin++) {
+        auto n = new node;
+        n->data = *begin;
+        cx_linked_list_link(prev, n, loc_prev, loc_next);
+        prev = n;
+    }
+    return node_test_data{first};
+}
+
+static node_test_data create_nodes_test_data(std::initializer_list<int> data) {
+    return create_nodes_test_data(data.begin(), data.end());
+}
+
+template<size_t N>
+struct int_test_data {
+    std::array<int, N> data;
+
+    int_test_data() {
+        cx_for_n (i, N) data[i] = ::rand(); // NOLINT(cert-msc50-cpp)
+    }
+};
+
+TEST(LinkedList_LowLevel, link_unlink) {
+    node a, b, c;
+
+    cx_linked_list_link(&a, &b, loc_prev, loc_next);
+    EXPECT_EQ(a.prev, nullptr);
+    EXPECT_EQ(a.next, &b);
+    EXPECT_EQ(b.prev, &a);
+    EXPECT_EQ(b.next, nullptr);
+
+    cx_linked_list_unlink(&a, &b, loc_prev, loc_next);
+    EXPECT_EQ(a.prev, nullptr);
+    EXPECT_EQ(a.next, nullptr);
+    EXPECT_EQ(b.prev, nullptr);
+    EXPECT_EQ(b.next, nullptr);
+
+    cx_linked_list_link(&b, &c, loc_prev, loc_next);
+    cx_linked_list_link(&a, &b, loc_prev, loc_next);
+    cx_linked_list_unlink(&b, &c, loc_prev, loc_next);
+    EXPECT_EQ(a.prev, nullptr);
+    EXPECT_EQ(a.next, &b);
+    EXPECT_EQ(b.prev, &a);
+    EXPECT_EQ(b.next, nullptr);
+    EXPECT_EQ(c.prev, nullptr);
+    EXPECT_EQ(c.next, nullptr);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_at) {
+    node a, b, c, d;
+    cx_linked_list_link(&a, &b, loc_prev, loc_next);
+    cx_linked_list_link(&b, &c, loc_prev, loc_next);
+    cx_linked_list_link(&c, &d, loc_prev, loc_next);
+
+    EXPECT_EQ(cx_linked_list_at(&a, 0, loc_next, 0), &a);
+    EXPECT_EQ(cx_linked_list_at(&a, 0, loc_next, 1), &b);
+    EXPECT_EQ(cx_linked_list_at(&a, 0, loc_next, 2), &c);
+    EXPECT_EQ(cx_linked_list_at(&a, 0, loc_next, 3), &d);
+    EXPECT_EQ(cx_linked_list_at(&a, 0, loc_next, 4), nullptr);
+
+    EXPECT_EQ(cx_linked_list_at(&b, 1, loc_prev, 0), &a);
+    EXPECT_EQ(cx_linked_list_at(&b, 1, loc_next, 1), &b);
+    EXPECT_EQ(cx_linked_list_at(&b, 1, loc_next, 2), &c);
+    EXPECT_EQ(cx_linked_list_at(&b, 1, loc_next, 3), &d);
+    EXPECT_EQ(cx_linked_list_at(&b, 1, loc_next, 4), nullptr);
+
+    EXPECT_EQ(cx_linked_list_at(&d, 3, loc_prev, 0), &a);
+    EXPECT_EQ(cx_linked_list_at(&d, 3, loc_prev, 1), &b);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_find) {
+    auto testdata = create_nodes_test_data({2, 4, 6, 8});
+    auto list = testdata.begin;
+    int s;
+
+    s = 2;
+    EXPECT_EQ(cx_linked_list_find(list, loc_next, loc_data, false, cmp_int, &s), 0);
+    s = 4;
+    EXPECT_EQ(cx_linked_list_find(list, loc_next, loc_data, false, cmp_int, &s), 1);
+    s = 6;
+    EXPECT_EQ(cx_linked_list_find(list, loc_next, loc_data, false, cmp_int, &s), 2);
+    s = 8;
+    EXPECT_EQ(cx_linked_list_find(list, loc_next, loc_data, false, cmp_int, &s), 3);
+    s = 10;
+    EXPECT_EQ(cx_linked_list_find(list, loc_next, loc_data, false, cmp_int, &s), 4);
+    s = -2;
+    EXPECT_EQ(cx_linked_list_find(list, loc_next, loc_data, false, cmp_int, &s), 4);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_compare) {
+    auto ta = create_nodes_test_data({2, 4, 6, 8});
+    auto tb = create_nodes_test_data({2, 4, 6});
+    auto tc = create_nodes_test_data({2, 4, 6, 9});
+    auto la = ta.begin, lb = tb.begin, lc = tc.begin;
+
+    EXPECT_GT(cx_linked_list_compare(la, lb, loc_next, loc_data, false, cmp_int), 0);
+    EXPECT_LT(cx_linked_list_compare(lb, la, loc_next, loc_data, false, cmp_int), 0);
+    EXPECT_GT(cx_linked_list_compare(lc, la, loc_next, loc_data, false, cmp_int), 0);
+    EXPECT_LT(cx_linked_list_compare(la, lc, loc_next, loc_data, false, cmp_int), 0);
+    EXPECT_EQ(cx_linked_list_compare(la, la, loc_next, loc_data, false, cmp_int), 0);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_add) {
+    // test with begin, end / prev, next
+    {
+        node nodes[4];
+        void *begin = nullptr, *end = nullptr;
+
+        cx_linked_list_add(&begin, &end, loc_prev, loc_next, &nodes[0]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[0]);
+        EXPECT_EQ(nodes[0].prev, nullptr);
+        EXPECT_EQ(nodes[0].next, nullptr);
+
+        cx_linked_list_add(&begin, &end, loc_prev, loc_next, &nodes[1]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[1]);
+        EXPECT_EQ(nodes[0].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, &nodes[0]);
+    }
+
+    // test with begin only / prev, next
+    {
+        node nodes[4];
+        void *begin = nullptr;
+
+        cx_linked_list_add(&begin, nullptr, loc_prev, loc_next, &nodes[0]);
+        EXPECT_EQ(begin, &nodes[0]);
+        cx_linked_list_add(&begin, nullptr, loc_prev, loc_next, &nodes[1]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(nodes[0].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, &nodes[0]);
+
+        cx_linked_list_add(&begin, nullptr, loc_prev, loc_next, &nodes[2]);
+        EXPECT_EQ(nodes[1].next, &nodes[2]);
+        EXPECT_EQ(nodes[2].prev, &nodes[1]);
+    }
+
+    // test with end only / prev, next
+    {
+        node nodes[4];
+        void *end = nullptr;
+
+        cx_linked_list_add(nullptr, &end, loc_prev, loc_next, &nodes[0]);
+        EXPECT_EQ(end, &nodes[0]);
+        cx_linked_list_add(nullptr, &end, loc_prev, loc_next, &nodes[1]);
+        EXPECT_EQ(end, &nodes[1]);
+        EXPECT_EQ(nodes[0].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, &nodes[0]);
+
+        cx_linked_list_add(nullptr, &end, loc_prev, loc_next, &nodes[2]);
+        EXPECT_EQ(end, &nodes[2]);
+        EXPECT_EQ(nodes[1].next, &nodes[2]);
+        EXPECT_EQ(nodes[2].prev, &nodes[1]);
+    }
+
+    // test with begin, end / next
+    {
+        node nodes[4];
+        void *begin = nullptr, *end = nullptr;
+
+        cx_linked_list_add(&begin, &end, -1, loc_next, &nodes[0]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[0]);
+        cx_linked_list_add(&begin, &end, -1, loc_next, &nodes[1]);
+        EXPECT_EQ(end, &nodes[1]);
+        EXPECT_EQ(nodes[0].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, nullptr);
+    }
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_prepend) {
+    // test with begin, end / prev, next
+    {
+        node nodes[4];
+        void *begin = nullptr, *end = nullptr;
+
+        cx_linked_list_prepend(&begin, &end, loc_prev, loc_next, &nodes[0]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[0]);
+        EXPECT_EQ(nodes[0].prev, nullptr);
+        EXPECT_EQ(nodes[0].next, nullptr);
+
+        cx_linked_list_prepend(&begin, &end, loc_prev, loc_next, &nodes[1]);
+        EXPECT_EQ(begin, &nodes[1]);
+        EXPECT_EQ(end, &nodes[0]);
+        EXPECT_EQ(nodes[1].next, &nodes[0]);
+        EXPECT_EQ(nodes[0].prev, &nodes[1]);
+    }
+
+    // test with begin only / prev, next
+    {
+        node nodes[4];
+        void *begin = nullptr;
+
+        cx_linked_list_prepend(&begin, nullptr, loc_prev, loc_next, &nodes[0]);
+        EXPECT_EQ(begin, &nodes[0]);
+        cx_linked_list_prepend(&begin, nullptr, loc_prev, loc_next, &nodes[1]);
+        EXPECT_EQ(begin, &nodes[1]);
+        EXPECT_EQ(nodes[1].next, &nodes[0]);
+        EXPECT_EQ(nodes[0].prev, &nodes[1]);
+
+        cx_linked_list_prepend(&begin, nullptr, loc_prev, loc_next, &nodes[2]);
+        EXPECT_EQ(begin, &nodes[2]);
+        EXPECT_EQ(nodes[2].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, &nodes[2]);
+    }
+
+    // test with end only / prev, next
+    {
+        node nodes[4];
+        void *end = nullptr;
+
+        cx_linked_list_prepend(nullptr, &end, loc_prev, loc_next, &nodes[0]);
+        EXPECT_EQ(end, &nodes[0]);
+        cx_linked_list_prepend(nullptr, &end, loc_prev, loc_next, &nodes[1]);
+        EXPECT_EQ(end, &nodes[0]);
+        EXPECT_EQ(nodes[1].next, &nodes[0]);
+        EXPECT_EQ(nodes[0].prev, &nodes[1]);
+
+        cx_linked_list_prepend(nullptr, &end, loc_prev, loc_next, &nodes[2]);
+        EXPECT_EQ(end, &nodes[0]);
+        EXPECT_EQ(nodes[2].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, &nodes[2]);
+    }
+
+    // test with begin, end / next
+    {
+        node nodes[4];
+        void *begin = nullptr, *end = nullptr;
+
+        cx_linked_list_prepend(&begin, &end, -1, loc_next, &nodes[0]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[0]);
+        cx_linked_list_prepend(&begin, &end, -1, loc_next, &nodes[1]);
+        cx_linked_list_prepend(&begin, &end, -1, loc_next, &nodes[2]);
+        EXPECT_EQ(begin, &nodes[2]);
+        EXPECT_EQ(end, &nodes[0]);
+        EXPECT_EQ(nodes[1].next, &nodes[0]);
+        EXPECT_EQ(nodes[2].next, &nodes[1]);
+        EXPECT_EQ(nodes[1].prev, nullptr);
+        EXPECT_EQ(nodes[0].prev, nullptr);
+    }
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_insert) {
+    // insert mid list
+    {
+        node nodes[4];
+        void *begin = &nodes[0], *end = &nodes[2];
+
+        cx_linked_list_link(&nodes[0], &nodes[1], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[1], &nodes[2], loc_prev, loc_next);
+
+        cx_linked_list_insert(&begin, &end, loc_prev, loc_next, &nodes[1], &nodes[3]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[2]);
+        EXPECT_EQ(nodes[1].next, &nodes[3]);
+        EXPECT_EQ(nodes[2].prev, &nodes[3]);
+        EXPECT_EQ(nodes[3].prev, &nodes[1]);
+        EXPECT_EQ(nodes[3].next, &nodes[2]);
+    }
+
+    // insert end
+    {
+        node nodes[4];
+        void *begin = &nodes[0], *end = &nodes[2];
+
+        cx_linked_list_link(&nodes[0], &nodes[1], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[1], &nodes[2], loc_prev, loc_next);
+
+        cx_linked_list_insert(&begin, &end, loc_prev, loc_next, &nodes[2], &nodes[3]);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[3]);
+        EXPECT_EQ(nodes[2].next, &nodes[3]);
+        EXPECT_EQ(nodes[3].prev, &nodes[2]);
+        EXPECT_EQ(nodes[3].next, nullptr);
+    }
+
+    // insert begin
+    {
+        node nodes[4];
+        void *begin = &nodes[0], *end = &nodes[2];
+
+        cx_linked_list_link(&nodes[0], &nodes[1], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[1], &nodes[2], loc_prev, loc_next);
+
+        cx_linked_list_insert(&begin, &end, loc_prev, loc_next, nullptr, &nodes[3]);
+        EXPECT_EQ(begin, &nodes[3]);
+        EXPECT_EQ(end, &nodes[2]);
+        EXPECT_EQ(nodes[0].prev, &nodes[3]);
+        EXPECT_EQ(nodes[3].prev, nullptr);
+        EXPECT_EQ(nodes[3].next, &nodes[0]);
+    }
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_insert_chain) {
+    // insert mid list
+    {
+        node nodes[5];
+        void *begin = &nodes[0], *end = &nodes[2];
+
+        cx_linked_list_link(&nodes[0], &nodes[1], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[1], &nodes[2], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[3], &nodes[4], loc_prev, loc_next);
+
+        cx_linked_list_insert_chain(&begin, &end, loc_prev, loc_next, &nodes[1], &nodes[3], nullptr);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[2]);
+        EXPECT_EQ(nodes[1].next, &nodes[3]);
+        EXPECT_EQ(nodes[2].prev, &nodes[4]);
+        EXPECT_EQ(nodes[3].prev, &nodes[1]);
+        EXPECT_EQ(nodes[4].next, &nodes[2]);
+    }
+
+    // insert end
+    {
+        node nodes[5];
+        void *begin = &nodes[0], *end = &nodes[2];
+
+        cx_linked_list_link(&nodes[0], &nodes[1], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[1], &nodes[2], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[3], &nodes[4], loc_prev, loc_next);
+
+        cx_linked_list_insert_chain(&begin, &end, loc_prev, loc_next, &nodes[2], &nodes[3], nullptr);
+        EXPECT_EQ(begin, &nodes[0]);
+        EXPECT_EQ(end, &nodes[4]);
+        EXPECT_EQ(nodes[2].next, &nodes[3]);
+        EXPECT_EQ(nodes[3].prev, &nodes[2]);
+        EXPECT_EQ(nodes[4].next, nullptr);
+    }
+
+    // insert begin
+    {
+        node nodes[5];
+        void *begin = &nodes[0], *end = &nodes[2];
+
+        cx_linked_list_link(&nodes[0], &nodes[1], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[1], &nodes[2], loc_prev, loc_next);
+        cx_linked_list_link(&nodes[3], &nodes[4], loc_prev, loc_next);
+
+        cx_linked_list_insert_chain(&begin, &end, loc_prev, loc_next, nullptr, &nodes[3], nullptr);
+        EXPECT_EQ(begin, &nodes[3]);
+        EXPECT_EQ(end, &nodes[2]);
+        EXPECT_EQ(nodes[0].prev, &nodes[4]);
+        EXPECT_EQ(nodes[3].prev, nullptr);
+        EXPECT_EQ(nodes[4].next, &nodes[0]);
+    }
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_first) {
+    auto testdata = create_nodes_test_data(3);
+    auto begin = testdata.begin;
+    EXPECT_EQ(cx_linked_list_first(begin, loc_prev), begin);
+    EXPECT_EQ(cx_linked_list_first(begin->next, loc_prev), begin);
+    EXPECT_EQ(cx_linked_list_first(begin->next->next, loc_prev), begin);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_last) {
+    auto testdata = create_nodes_test_data(3);
+    auto begin = testdata.begin;
+    auto end = begin->next->next;
+    EXPECT_EQ(cx_linked_list_last(begin, loc_next), end);
+    EXPECT_EQ(cx_linked_list_last(begin->next, loc_next), end);
+    EXPECT_EQ(cx_linked_list_last(begin->next->next, loc_next), end);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_prev) {
+    auto testdata = create_nodes_test_data(3);
+    auto begin = testdata.begin;
+    EXPECT_EQ(cx_linked_list_prev(begin, loc_next, begin), nullptr);
+    EXPECT_EQ(cx_linked_list_prev(begin, loc_next, begin->next), begin);
+    EXPECT_EQ(cx_linked_list_prev(begin, loc_next, begin->next->next), begin->next);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_remove) {
+    auto testdata = create_nodes_test_data({2, 4, 6});
+    auto begin = reinterpret_cast<void *>(testdata.begin);
+    auto first = testdata.begin;
+    auto second = first->next;
+    auto third = second->next;
+    auto end = reinterpret_cast<void *>(third);
+
+    cx_linked_list_remove(&begin, &end, loc_prev, loc_next, second);
+    EXPECT_EQ(begin, first);
+    EXPECT_EQ(end, third);
+    EXPECT_EQ(first->prev, nullptr);
+    EXPECT_EQ(first->next, third);
+    EXPECT_EQ(third->prev, first);
+    EXPECT_EQ(third->next, nullptr);
+
+    cx_linked_list_remove(&begin, &end, loc_prev, loc_next, third);
+    EXPECT_EQ(begin, first);
+    EXPECT_EQ(end, first);
+    EXPECT_EQ(first->prev, nullptr);
+    EXPECT_EQ(first->next, nullptr);
+
+    cx_linked_list_remove(&begin, &end, loc_prev, loc_next, first);
+    EXPECT_EQ(begin, nullptr);
+    EXPECT_EQ(end, nullptr);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_size) {
+    EXPECT_EQ(cx_linked_list_size(nullptr, loc_next), 0);
+
+    {
+        auto testdata = create_nodes_test_data(5);
+        EXPECT_EQ(cx_linked_list_size(testdata.begin, loc_next), 5);
+    }
+
+    {
+        auto testdata = create_nodes_test_data(13);
+        EXPECT_EQ(cx_linked_list_size(testdata.begin, loc_next), 13);
+    }
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_sort) {
+    int_test_data<1000> testdata;
+    std::array<int, 1000> sorted{};
+    std::partial_sort_copy(testdata.data.begin(), testdata.data.end(), sorted.begin(), sorted.end());
+
+    auto scrambled = create_nodes_test_data(testdata.data.begin(), testdata.data.end());
+    void *begin = scrambled.begin;
+    void *end = cx_linked_list_last(begin, loc_next);
+
+    cx_linked_list_sort(&begin, &end, loc_prev, loc_next, loc_data,
+                        false, cmp_int);
+
+    node *check = reinterpret_cast<node *>(begin);
+    node *check_last = nullptr;
+    cx_for_n (i, sorted.size()) {
+        EXPECT_EQ(check->data, sorted[i]);
+        EXPECT_EQ(check->prev, check_last);
+        if (i < sorted.size() - 1) {
+            ASSERT_NE(check->next, nullptr);
+        }
+        check_last = check;
+        check = check->next;
+    }
+    EXPECT_EQ(check, nullptr);
+    EXPECT_EQ(end, check_last);
+}
+
+TEST(LinkedList_LowLevel, cx_linked_list_reverse) {
+    auto testdata = create_nodes_test_data({2, 4, 6, 8});
+    auto expected = create_nodes_test_data({8, 6, 4, 2});
+
+    auto begin = reinterpret_cast<void *>(testdata.begin);
+    auto end = cx_linked_list_last(begin, loc_next);
+    auto orig_begin = begin, orig_end = end;
+
+    cx_linked_list_reverse(&begin, &end, loc_prev, loc_next);
+    EXPECT_EQ(end, orig_begin);
+    EXPECT_EQ(begin, orig_end);
+    EXPECT_EQ(cx_linked_list_compare(begin, expected.begin, loc_next, loc_data, 0, cmp_int), 0);
+}
+
+class HighLevelTest : public ::testing::Test {
+    mutable std::unordered_set<CxList *> lists;
+protected:
+    void SetUp() override {
+        cxTestingAllocatorReset();
+    }
+
+    void TearDown() override {
+        for (auto &&l: lists) cxListDestroy(l);
+        EXPECT_TRUE(cxTestingAllocatorVerify());
+    }
+
+    static constexpr size_t testdata_len = 250;
+    int_test_data<testdata_len> testdata;
+
+    auto autofree(CxList *list) const -> CxList * {
+        lists.insert(list);
+        return list;
+    }
+
+    auto linkedListFromTestData() const -> CxList * {
+        return autofree(
+                cxLinkedListFromArray(
+                        cxTestingAllocator,
+                        cmp_int,
+                        sizeof(int),
+                        testdata_len,
+                        testdata.data.data()
+                )
+        );
+    }
+
+    auto pointerLinkedListFromTestData() const -> CxList * {
+        auto list = autofree(cxPointerLinkedListCreate(cxTestingAllocator, cmp_int));
+        cx_for_n(i, testdata_len) cxListAdd(list, &testdata.data[i]);
+        return list;
+    }
+
+    static void verifyCreate(CxList *list) {
+        EXPECT_EQ(list->size, 0);
+        EXPECT_EQ(list->capacity, (size_t) -1);
+        EXPECT_EQ(list->allocator, cxTestingAllocator);
+        EXPECT_EQ(list->cmpfunc, cmp_int);
+    }
+
+    void verifyAdd(CxList *list, bool write_through) {
+        auto len = testdata_len;
+        cx_for_n (i, len) EXPECT_EQ(cxListAdd(list, &testdata.data[i]), 0);
+        EXPECT_EQ(list->size, len);
+        EXPECT_GE(list->capacity, list->size);
+        cx_for_n (i, len) EXPECT_EQ(*(int *) cxListAt(list, i), testdata.data[i]);
+        cx_for_n (i, len) ++testdata.data[i];
+        if (write_through) {
+            cx_for_n (i, len) EXPECT_EQ(*(int *) cxListAt(list, i), testdata.data[i]);
+        } else {
+            cx_for_n (i, len) EXPECT_EQ(*(int *) cxListAt(list, i), testdata.data[i] - 1);
+        }
+    }
+
+    static void verifyInsert(CxList *list) {
+        int a = 5, b = 47, c = 13, d = 42;
+
+        EXPECT_NE(cxListInsert(list, 1, &a), 0);
+        EXPECT_EQ(list->size, 0);
+        EXPECT_EQ(cxListInsert(list, 0, &a), 0);
+        EXPECT_EQ(list->size, 1);
+        EXPECT_EQ(cxListInsert(list, 0, &b), 0);
+        EXPECT_EQ(list->size, 2);
+        EXPECT_EQ(cxListInsert(list, 1, &c), 0);
+        EXPECT_EQ(list->size, 3);
+        EXPECT_EQ(cxListInsert(list, 3, &d), 0);
+
+        EXPECT_EQ(list->size, 4);
+        EXPECT_GE(list->capacity, list->size);
+
+        EXPECT_EQ(*(int *) cxListAt(list, 0), 47);
+        EXPECT_EQ(*(int *) cxListAt(list, 1), 13);
+        EXPECT_EQ(*(int *) cxListAt(list, 2), 5);
+        EXPECT_EQ(*(int *) cxListAt(list, 3), 42);
+    }
+
+    void verifyRemove(CxList *list) const {
+        EXPECT_EQ(cxListRemove(list, 2), 0);
+        EXPECT_EQ(cxListRemove(list, 4), 0);
+        EXPECT_EQ(list->size, testdata_len - 2);
+        EXPECT_GE(list->capacity, list->size);
+        EXPECT_EQ(*(int *) cxListAt(list, 0), testdata.data[0]);
+        EXPECT_EQ(*(int *) cxListAt(list, 1), testdata.data[1]);
+        EXPECT_EQ(*(int *) cxListAt(list, 2), testdata.data[3]);
+        EXPECT_EQ(*(int *) cxListAt(list, 3), testdata.data[4]);
+        EXPECT_EQ(*(int *) cxListAt(list, 4), testdata.data[6]);
+
+        EXPECT_EQ(cxListRemove(list, 0), 0);
+        EXPECT_EQ(list->size, testdata_len - 3);
+        EXPECT_GE(list->capacity, list->size);
+        EXPECT_EQ(*(int *) cxListAt(list, 0), testdata.data[1]);
+        EXPECT_EQ(*(int *) cxListAt(list, 1), testdata.data[3]);
+
+        EXPECT_NE(cxListRemove(list, testdata_len), 0);
+    }
+
+    void verifyAt(CxList *list) const {
+        auto len = testdata_len;
+        EXPECT_EQ(list->size, len);
+        cx_for_n (i, list->size) EXPECT_EQ(*(int *) cxListAt(list, i), testdata.data[i]);
+        EXPECT_EQ(cxListAt(list, list->size), nullptr);
+    }
+
+    void verifyFind(CxList *list) const {
+        cx_for_n (attempt, 25) {
+            size_t exp = rand() % testdata_len; // NOLINT(cert-msc50-cpp)
+            int val = testdata.data[exp];
+            // randomly picked number could occur earlier in list - find first position
+            cx_for_n (i, exp) {
+                if (testdata.data[i] == val) {
+                    exp = i;
+                    break;
+                }
+            }
+            EXPECT_EQ(cxListFind(list, &val), exp);
+        }
+    }
+
+    void verifySort(CxList *list) const {
+        std::array<int, testdata_len> expected{};
+        std::partial_sort_copy(testdata.data.begin(), testdata.data.end(), expected.begin(), expected.end());
+        cxListSort(list);
+        cx_for_n (i, testdata_len) ASSERT_EQ(*(int *) cxListAt(list, i), expected[i]);
+    }
+
+    void verifyIterator(CxList *list) const {
+        int i = 0;
+        CxIterator iter = cxListBegin(list);
+        cx_foreach(int*, x, iter) {
+            ASSERT_EQ(iter.index, (size_t) (i + 1) / 2);
+            ASSERT_EQ(*x, testdata.data[i]);
+            if (i % 2 == 1) iter.remove = true;
+            i++;
+        }
+        auto len = testdata_len;
+        EXPECT_EQ(i, len);
+        ASSERT_EQ(list->size, len / 2);
+        cx_for_n(j, len / 2) ASSERT_EQ(*(int *) cxListAt(list, j), testdata.data[j * 2]);
+    }
+
+    static void verifyInsertViaIterator(CxList *list) {
+        int newdata[] = {10, 20, 30, 40, 50};
+
+        CxIterator iter = cxListIterator(list, 2);
+        EXPECT_TRUE(cxIteratorValid(&iter));
+        EXPECT_EQ(iter.index, 2);
+        EXPECT_EQ(*(int *) cxIteratorCurrent(&iter), 2);
+        cxListInsertAfter(&iter, &newdata[0]);
+        EXPECT_TRUE(cxIteratorValid(&iter));
+        EXPECT_EQ(iter.index, 2);
+        EXPECT_EQ(*(int *) cxIteratorCurrent(&iter), 2);
+        cxListInsertBefore(&iter, &newdata[1]);
+        EXPECT_TRUE(cxIteratorValid(&iter));
+        EXPECT_EQ(iter.index, 3);
+        EXPECT_EQ(*(int *) cxIteratorCurrent(&iter), 2);
+
+        iter = cxListBegin(list);
+        cxListInsertBefore(&iter, &newdata[2]);
+        EXPECT_TRUE(cxIteratorValid(&iter));
+        EXPECT_EQ(iter.index, 1);
+        EXPECT_EQ(*(int *) cxIteratorCurrent(&iter), 0);
+        iter = cxListIterator(list, list->size);
+        cxListInsertBefore(&iter, &newdata[3]);
+        EXPECT_FALSE(cxIteratorValid(&iter));
+        EXPECT_EQ(iter.index, 9);
+        iter = cxListIterator(list, list->size);
+        cxListInsertAfter(&iter, &newdata[4]);
+        EXPECT_FALSE(cxIteratorValid(&iter));
+        EXPECT_EQ(iter.index, 10);
+
+        int expdata[] = {30, 0, 1, 20, 2, 10, 3, 4, 40, 50};
+        cx_for_n (j, 10) EXPECT_EQ(*(int *) cxListAt(list, j), expdata[j]);
+    }
+};
+
+class LinkedList : public HighLevelTest {
+};
+
+class PointerLinkedList : public HighLevelTest {
+};
+
+TEST_F(LinkedList, cxLinkedListCreate) {
+    CxList *list = autofree(cxLinkedListCreate(cxTestingAllocator, cmp_int, sizeof(int)));
+    EXPECT_EQ(list->itemsize, sizeof(int));
+    verifyCreate(list);
+}
+
+TEST_F(PointerLinkedList, cxPointerLinkedListCreate) {
+    CxList *list = autofree(cxPointerLinkedListCreate(cxTestingAllocator, cmp_int));
+    EXPECT_EQ(list->itemsize, sizeof(void *));
+    verifyCreate(list);
+}
+
+TEST_F(LinkedList, cxLinkedListFromArray) {
+    CxList *expected = autofree(cxLinkedListCreate(cxTestingAllocator, cmp_int, sizeof(int)));
+    cx_for_n (i, testdata_len) cxListAdd(expected, &testdata.data[i]);
+    CxList *list = autofree(cxLinkedListFromArray(cxTestingAllocator, cmp_int, sizeof(int),
+                                                  testdata_len, testdata.data.data()));
+    EXPECT_EQ(cxListCompare(list, expected), 0);
+}
+
+TEST_F(LinkedList, cxListAdd) {
+    CxList *list = autofree(cxLinkedListCreate(cxTestingAllocator, cmp_int, sizeof(int)));
+    verifyAdd(list, false);
+}
+
+TEST_F(PointerLinkedList, cxListAdd) {
+    CxList *list = autofree(cxPointerLinkedListCreate(cxTestingAllocator, cmp_int));
+    verifyAdd(list, true);
+}
+
+TEST_F(LinkedList, cxListInsert) {
+    verifyInsert(autofree(cxLinkedListCreate(cxTestingAllocator, cmp_int, sizeof(int))));
+}
+
+TEST_F(PointerLinkedList, cxListInsert) {
+    verifyInsert(autofree(cxPointerLinkedListCreate(cxTestingAllocator, cmp_int)));
+}
+
+TEST_F(LinkedList, cxListRemove) {
+    verifyRemove(linkedListFromTestData());
+}
+
+TEST_F(PointerLinkedList, cxListRemove) {
+    verifyRemove(pointerLinkedListFromTestData());
+}
+
+TEST_F(LinkedList, cxListAt) {
+    verifyAt(linkedListFromTestData());
+}
+
+TEST_F(PointerLinkedList, cxListAt) {
+    verifyAt(pointerLinkedListFromTestData());
+}
+
+TEST_F(LinkedList, cxListFind) {
+    verifyFind(linkedListFromTestData());
+}
+
+TEST_F(PointerLinkedList, cxListFind) {
+    verifyFind(pointerLinkedListFromTestData());
+}
+
+TEST_F(LinkedList, cxListSort) {
+    verifySort(linkedListFromTestData());
+}
+
+TEST_F(PointerLinkedList, cxListSort) {
+    verifySort(pointerLinkedListFromTestData());
+}
+
+TEST_F(LinkedList, Iterator) {
+    verifyIterator(linkedListFromTestData());
+}
+
+TEST_F(PointerLinkedList, Iterator) {
+    verifyIterator(pointerLinkedListFromTestData());
+}
+
+TEST_F(LinkedList, InsertViaIterator) {
+    int fivenums[] = {0, 1, 2, 3, 4, 5};
+    CxList *list = autofree(cxLinkedListFromArray(cxTestingAllocator, cmp_int, sizeof(int), 5, fivenums));
+    verifyInsertViaIterator(list);
+}
+
+TEST_F(PointerLinkedList, InsertViaIterator) {
+    int fivenums[] = {0, 1, 2, 3, 4, 5};
+    CxList *list = autofree(cxPointerLinkedListCreate(cxTestingAllocator, cmp_int));
+    cx_for_n (i, 5) cxListAdd(list, &fivenums[i]);
+    verifyInsertViaIterator(list);
+}