--- /dev/null
+#include <ccan/bdelta/bdelta.h>
+#include <ccan/bdelta/bdelta.c>
+#include <ccan/tap/tap.h>
+
+static int test_trivial(const char *old, const char *new_)
+{
+ void *patch;
+ size_t patch_size;
+ BDELTAcode rc;
+
+ void *new2;
+ size_t new2_size;
+
+ rc = bdelta_diff(old, strlen(old), new_, strlen(new_), &patch, &patch_size);
+ if (rc != BDELTA_OK) {
+ bdelta_perror("bdelta_diff", rc);
+ return 0;
+ }
+
+ if (patch_size > strlen(new_) + 1) {
+ fprintf(stderr, "bdelta_diff produced a patch larger than a simple literal emitting the new string.\n");
+ return 0;
+ }
+
+ rc = bdelta_patch(old, strlen(old), patch, patch_size, &new2, &new2_size);
+ if (rc != BDELTA_OK) {
+ bdelta_perror("bdelta_patch", rc);
+ return 0;
+ }
+
+ if (new2_size != strlen(new_) || strcmp(new2, new_) != 0) {
+ fprintf(stderr, "patch(old, diff(old, new)) != new\n");
+ return 0;
+ }
+
+ /* Make sure bdelta_diff properly discards unwanted return values. */
+ rc = bdelta_diff(old, strlen(old), new_, strlen(new_), NULL, NULL);
+ if (rc != BDELTA_OK) {
+ bdelta_perror("bdelta_diff (second time)", rc);
+ return 0;
+ }
+
+ free(new2);
+ free(patch);
+ return 1;
+}
+
+int main(void)
+{
+ plan_tests(13);
+
+ ok1(test_trivial("abcabba", "cbabac"));
+ ok1(test_trivial("aaabbbcdaabcc", "aaabbcdaabeca"));
+ ok1(test_trivial("aaaaaaaa", "bbbbbbbb"));
+ ok1(test_trivial("aaaaaaaa", ""));
+ ok1(test_trivial("", "bbbbbbbb"));
+ ok1(test_trivial("", ""));
+ ok1(test_trivial("aaaaaaaa", "aaaaaaaabbbbbbbb"));
+ ok1(test_trivial("aaaaaaaa", "bbbbbbbbaaaaaaaa"));
+ ok1(test_trivial("aaaaaaaabbbbbbbb", "aaaaaaaa"));
+ ok1(test_trivial("aaaaaaaabbbbbbbb", "bbbbbbbb"));
+ ok1(test_trivial("aaaaaaaabbbbbbbb", "bbbbbbbb"));
+ ok1(test_trivial("abababababababab", "babababababababa"));
+ ok1(test_trivial("aababcabcdabcde", "aababcabcdabcde"));
+
+ return exit_status();
+}