add tests

main_test.go

@@ -0,0 +1,17 @@
+package main
+
+import "testing"
+
+func TestSubExists(t *testing.T) {
+	dummyRecords := make([]DomainRecord, 0)
+
+	doesExist, recID := subExists(dummyRecords)
+
+	if doesExist {
+		t.Errorf("subExists() returned true, should have been false")
+	}
+
+	if recID != 0 {
+		t.Errorf("subExists() returned %v for recID, should be 0", recID)
+	}
+}