tests/test_tree.c

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2023 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
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#include "cx/tree.h"

#include "cx/test.h"

typedef struct tree_node {
    struct tree_node *parent;
    struct tree_node *next;
    struct tree_node *prev;
    struct tree_node *children;
    int data;
} tree_node;

#define tree_node_layout \
    offsetof(tree_node, parent), offsetof(tree_node, children), \
    offsetof(tree_node, prev), offsetof(tree_node, next)

CX_TEST(test_tree_link_new_child) {
    tree_node parent = {0};
    tree_node child = {0};

    CX_TEST_DO {
        cx_tree_link(&parent, &child, tree_node_layout);
        CX_TEST_ASSERT(parent.next == NULL);
        CX_TEST_ASSERT(parent.prev == NULL);
        CX_TEST_ASSERT(parent.parent == NULL);
        CX_TEST_ASSERT(parent.children == &child);
        CX_TEST_ASSERT(child.parent == &parent);
        CX_TEST_ASSERT(child.next == NULL);
        CX_TEST_ASSERT(child.prev == NULL);
        CX_TEST_ASSERT(child.children == NULL);
    }
}

CX_TEST(test_tree_link_add_child) {
    tree_node parent = {0};
    tree_node child1 = {0};
    tree_node child2 = {0};
    tree_node child3 = {0};

    CX_TEST_DO {
        cx_tree_link(&parent, &child1, tree_node_layout);
        cx_tree_link(&parent, &child2, tree_node_layout);
        cx_tree_link(&parent, &child3, tree_node_layout);
        CX_TEST_ASSERT(parent.next == NULL);
        CX_TEST_ASSERT(parent.prev == NULL);
        CX_TEST_ASSERT(parent.parent == NULL);
        CX_TEST_ASSERT(parent.children == &child3);

        CX_TEST_ASSERT(child1.parent == &parent);
        CX_TEST_ASSERT(child2.parent == &parent);
        CX_TEST_ASSERT(child3.parent == &parent);
        CX_TEST_ASSERT(child1.children == NULL);
        CX_TEST_ASSERT(child2.children == NULL);
        CX_TEST_ASSERT(child3.children == NULL);

        CX_TEST_ASSERT(child3.prev == NULL);
        CX_TEST_ASSERT(child3.next == &child2);
        CX_TEST_ASSERT(child2.prev == &child3);
        CX_TEST_ASSERT(child2.next == &child1);
        CX_TEST_ASSERT(child1.prev == &child2);
        CX_TEST_ASSERT(child1.next == NULL);
    }
}

CX_TEST(test_tree_link_move_to_other_parent) {
    tree_node parent = {0};
    tree_node child1 = {0};
    tree_node child2 = {0};
    tree_node child3 = {0};
    cx_tree_link(&parent, &child1, tree_node_layout);
    cx_tree_link(&parent, &child2, tree_node_layout);
    cx_tree_link(&parent, &child3, tree_node_layout);

    CX_TEST_DO {
        cx_tree_link(&child3, &child2, tree_node_layout);

        CX_TEST_ASSERT(parent.next == NULL);
        CX_TEST_ASSERT(parent.prev == NULL);
        CX_TEST_ASSERT(parent.parent == NULL);
        CX_TEST_ASSERT(parent.children == &child3);

        CX_TEST_ASSERT(child1.parent == &parent);
        CX_TEST_ASSERT(child2.parent == &child3);
        CX_TEST_ASSERT(child3.parent == &parent);
        CX_TEST_ASSERT(child1.children == NULL);
        CX_TEST_ASSERT(child2.children == NULL);
        CX_TEST_ASSERT(child3.children == &child2);

        CX_TEST_ASSERT(child3.prev == NULL);
        CX_TEST_ASSERT(child3.next == &child1);
        CX_TEST_ASSERT(child1.prev == &child3);
        CX_TEST_ASSERT(child1.next == NULL);

        CX_TEST_ASSERT(child2.prev == NULL);
        CX_TEST_ASSERT(child2.next == NULL);
    }
}

CX_TEST(test_tree_unlink) {
    tree_node parent = {0};
    tree_node child1 = {0};
    tree_node child2 = {0};
    tree_node child3 = {0};
    cx_tree_link(&parent, &child1, tree_node_layout);
    cx_tree_link(&parent, &child3, tree_node_layout);
    cx_tree_link(&child3, &child2, tree_node_layout);

    CX_TEST_DO {
        cx_tree_unlink(&child3, tree_node_layout);

        CX_TEST_ASSERT(parent.next == NULL);
        CX_TEST_ASSERT(parent.prev == NULL);
        CX_TEST_ASSERT(parent.parent == NULL);
        CX_TEST_ASSERT(parent.children == &child1);

        CX_TEST_ASSERT(child1.parent == &parent);
        CX_TEST_ASSERT(child1.children == NULL);
        CX_TEST_ASSERT(child1.prev == NULL);
        CX_TEST_ASSERT(child1.next == NULL);

        // child 3 is unlinked
        CX_TEST_ASSERT(child3.parent == NULL);
        CX_TEST_ASSERT(child3.prev == NULL);
        CX_TEST_ASSERT(child3.next == NULL);

        // child 2 is still child of the unlinked child 3
        CX_TEST_ASSERT(child3.children == &child2);
        CX_TEST_ASSERT(child2.parent == &child3);
        CX_TEST_ASSERT(child2.children == NULL);
        CX_TEST_ASSERT(child2.prev == NULL);
        CX_TEST_ASSERT(child2.next == NULL);
    }
}

CxTestSuite *cx_test_suite_tree_low_level(void) {
    CxTestSuite *suite = cx_test_suite_new("tree (low level)");

    cx_test_register(suite, test_tree_link_new_child);
    cx_test_register(suite, test_tree_link_add_child);
    cx_test_register(suite, test_tree_link_move_to_other_parent);
    cx_test_register(suite, test_tree_unlink);

    return suite;
}