fixed a runtime error in fix(), added TestTags & TestAutomationItemsClose

Author: r-luyckx

connection_test.go

@@ -142,6 +142,22 @@ func TestGetTags(t *testing.T) {
 	}
 }
 
+func TestTags(t *testing.T) {
+	var want []string
+	client := &opcConnectionImpl{}
+	tags := client.Tags()
+	if !reflect.DeepEqual(tags, want) {
+		fmt.Printf("actual: %+v\n", tags)
+		fmt.Printf("Want: %+v\n", want)
+		t.Error("Tags() should return a empty array of strings")
+	}
+}
+
+func TestAutomationItemsClose(t *testing.T) {
+	conn := &opcConnectionImpl{}
+	conn.AutomationItems.Close()
+}
+
 func TestOpcRead(t *testing.T) {
 	client, _ := NewConnection(
 		"Graybox.Simulator",

connection_windows.go

@@ -319,11 +319,13 @@ func (ai *AutomationItems) writeToOpc(opcitem *ole.IDispatch, value interface{})
 
 //Close closes the OLE objects in AutomationItems.
 func (ai *AutomationItems) Close() {
-	for key, opcitem := range ai.items {
-		opcitem.Release()
-		delete(ai.items, key)
+	if ai != nil {
+		for key, opcitem := range ai.items {
+			opcitem.Release()
+			delete(ai.items, key)
+		}
+		ai.addItemObject.Release()
 	}
-	ai.addItemObject.Release()
 }
 
 //NewAutomationItems returns a new AutomationItems instance.
@@ -393,10 +395,13 @@ func (conn *opcConnectionImpl) Read() map[string]Item {
 //Tags returns the currently active tags
 func (conn *opcConnectionImpl) Tags() []string {
 	var tags []string
-	for tag, _ := range conn.AutomationItems.items {
-		tags = append(tags, tag)
+	if conn.AutomationItems != nil {
+		for tag, _ := range conn.AutomationItems.items {
+			tags = append(tags, tag)
+		}
 	}
 	return tags
+
 }
 
 //fix tries to reconnect if connection is lost by creating a new connection