8.7 Testing

The testing code harbors no surprises.

332. <tavl-test.c 332> =
<Program License 2>
#include <assert.h>
#include <limits.h>
#include <stdio.h>
#include "tavl.h"
#include "test.h"

<TBST print function; tbst => tavl 293>
<BST traverser check function; bst => tavl 105>
<Compare two TAVL trees for structure and content 333>
<Recursively verify TAVL tree structure 334>
<AVL tree verify function; avl => tavl 192>
<BST test function; bst => tavl 101>
<BST overflow test function; bst => tavl 123>

333. <Compare two TAVL trees for structure and content 333> =
static int 
compare_trees (struct tavl_node *a, struct tavl_node *b) 
{
  int okay;

  if (a == NULL || b == NULL) 
    {
      if (a != NULL || b != NULL) 
        {
          printf (" a=%d b=%d\n",
                  a ? *(int *) a->tavl_data : -1, 
                  b ? *(int *) b->tavl_data : -1);
          assert (0);
        }
      return 1;
    }
  assert (a != b);

  if (*(int *) a->tavl_data != *(int *) b->tavl_data
      || a->tavl_tag[0] != b->tavl_tag[0] 
      || a->tavl_tag[1] != b->tavl_tag[1]
      || a->tavl_balance != b->tavl_balance) 
    {
      printf (" Copied nodes differ: a=%d (bal=%d) b=%d (bal=%d) a:",
              *(int *) a->tavl_data, a->tavl_balance,
              *(int *) b->tavl_data, b->tavl_balance);

      if (a->tavl_tag[0] == TAVL_CHILD) 
        printf ("l");
      if (a->tavl_tag[1] == TAVL_CHILD) 
        printf ("r");

      printf (" b:");
      if (b->tavl_tag[0] == TAVL_CHILD) 
        printf ("l");
      if (b->tavl_tag[1] == TAVL_CHILD) 
        printf ("r");

      printf ("\n");
      return 0;
    }

  if (a->tavl_tag[0] == TAVL_THREAD)
    assert ((a->tavl_link[0] == NULL) != (a->tavl_link[0] != b->tavl_link[0]));
  if (a->tavl_tag[1] == TAVL_THREAD)
    assert ((a->tavl_link[1] == NULL) != (a->tavl_link[1] != b->tavl_link[1]));

  okay = 1;
  if (a->tavl_tag[0] == TAVL_CHILD)
    okay &= compare_trees (a->tavl_link[0], b->tavl_link[0]);
  if (a->tavl_tag[1] == TAVL_CHILD)
    okay &= compare_trees (a->tavl_link[1], b->tavl_link[1]);
  return okay;
}

This code is included in 332.

334. <Recursively verify TAVL tree structure 334> =
static void 
recurse_verify_tree (struct tavl_node *node, int *okay, size_t *count, 
                     int min, int max, int *height) 
{
  int d;                /* Value of this node's data. */
  size_t subcount[2];   /* Number of nodes in subtrees. */
  int subheight[2];     /* Heights of subtrees. */

  if (node == NULL) 
    {
      *count = 0;
      *height = 0;
      return;
    }
  d = *(int *) node->tavl_data;

  <Verify binary search tree ordering 115>

  subcount[0] = subcount[1] = 0;
  subheight[0] = subheight[1] = 0;
  if (node->tavl_tag[0] == TAVL_CHILD)
    recurse_verify_tree (node->tavl_link[0], okay, &subcount[0], 
                         min, d -  1, &subheight[0]);
  if (node->tavl_tag[1] == TAVL_CHILD)
    recurse_verify_tree (node->tavl_link[1], okay, &subcount[1], 
                         d + 1, max, &subheight[1]);
  *count = 1 + subcount[0] + subcount[1];
  *height = 1 + (subheight[0] > subheight[1] ? subheight[0] : subheight[1]);

  <Verify AVL node balance factor; avl => tavl 191>
}

This code is included in 332.

8.6 Copying

8 Threaded AVL Trees

9 Threaded Red-Black Trees