Add some more info to the debugging dump.

src/patricia.c

@@ -353,10 +353,14 @@ pt_print_tree(struct pt_y *y, struct vsb *sb, char **strings)
 	VSB_printf(sb, "leaf[0] = %p\n", y->leaf[0]);
 	VSB_printf(sb, "leaf[1] = %p\n", y->leaf[1]);
 	VSB_printf(sb, "idx = %u\n", y->idx);
-	if (strings[y->idx] != NULL)
-		VSB_printf(sb, "strings[idx] = %s\n", strings[y->idx]);
 	VSB_printf(sb, "off = %u\n", y->off);
 	VSB_printf(sb, "len = %u\n", y->len);
+	AN(strings[y->idx]);
+	VSB_printf(sb, "strings[idx] = %s\n", strings[y->idx]);
+	VSB_printf(sb, "strings[idx][0]..[off] = %.*s\n", y->off,
+		   strings[y->idx]);
+	VSB_printf(sb, "strings[idx][off]..[off+len] = %.*s\n", y->len,
+		   strings[y->idx] + y->off);
 	VSB_printf(sb, "bitmask = 0x%02x\n\n", y->bitmask);
 
 	if (y->leaf[0] != NULL)