diff --git a/if_test.v b/if_test.v
index cac3286..2a81aaa 100644
--- a/if_test.v
+++ b/if_test.v
@@ -1,20 +1,29 @@
 import netio
 
-fn test_name_to_index() {
-	assert netio.name_to_index('lo')! == 1
-}
-
-fn test_index_to_name() {
-	assert netio.index_to_name(1)! == 'lo'
-}
-
 fn test_network_interfaces() {
 	ifs := netio.network_interfaces()!
 	// dump(ifs)
 	assert ifs.len > 0
 }
 
-fn test_find_network_interface() {
-	assert netio.find_network_interface('lo')!.name == 'lo'
-	assert netio.find_network_interface('1')!.index == 1
+fn test_name_to_index() {
+	ifs := netio.network_interfaces()!
+	iface := ifs[0]
+	dump(iface)
+	assert netio.name_to_index(iface.name)! == iface.index
+}
+
+fn test_index_to_name() {
+	ifs := netio.network_interfaces()!
+	iface := ifs[0]
+	dump(iface)
+	assert netio.index_to_name(iface.index)! == iface.name
+}
+
+fn test_find_network_interface() {
+	ifs := netio.network_interfaces()!
+	iface := ifs[0]
+	dump(iface)
+	assert netio.find_network_interface(iface.name)!.name == iface.name
+	assert netio.find_network_interface(iface.index.str())!.index == iface.index
 }