--- /dev/null
+#include <ccan/htable/htable.h>
+#include <ccan/htable/htable.c>
+#include <ccan/tap/tap.h>
+#include <stdbool.h>
+
+struct data {
+ size_t key;
+};
+
+/* Hash is simply key itself. */
+static size_t hash(const void *e, void *unused)
+{
+ struct data *d = (struct data *)e;
+
+ return d->key;
+}
+
+static bool eq(const void *e, void *k)
+{
+ struct data *d = (struct data *)e;
+ size_t *key = (size_t *)k;
+
+ return (d->key == *key);
+}
+
+int main(void)
+{
+ struct htable table;
+ struct data *d0, *d1;
+
+ plan_tests(6);
+
+ d1 = malloc(sizeof(struct data));
+ d1->key = 1;
+ d0 = malloc(sizeof(struct data));
+ d0->key = 0;
+
+ htable_init(&table, hash, NULL);
+
+ htable_add(&table, d0->key, d0);
+ htable_add(&table, d1->key, d1);
+
+ ok1(table.elems == 2);
+ ok1(htable_get(&table, 1, eq, &d1->key) == d1);
+ ok1(htable_get(&table, 0, eq, &d0->key) == d0);
+ htable_clear(&table);
+
+ /* Now add in reverse order, should still be OK. */
+ htable_add(&table, d1->key, d1);
+ htable_add(&table, d0->key, d0);
+
+ ok1(table.elems == 2);
+ ok1(htable_get(&table, 1, eq, &d1->key) == d1);
+ ok1(htable_get(&table, 0, eq, &d0->key) == d0);
+ htable_clear(&table);
+
+ free(d0);
+ free(d1);
+ return exit_status();
+}
+