Add more tests for Enum Editor (#836)

* Add more tests for Enum Editor

* Add wx EnumEditor tests

* Add missing skipif decorator

* Add issue references to FIXMEs

* Address review comments

Author: ievacerny

traitsui/tests/_tools.py

@@ -177,6 +177,32 @@ def get_dialog_size(ui_control):
         return ui_control.size().width(), ui_control.size().height()
 
 
+def get_all_button_status(control):
+    """Get status of all 2-state (wx) or checkable (qt) buttons under given
+    control.
+
+    Assumes all sizer children (wx) or layout items (qt) are buttons.
+    """
+    button_status = []
+
+    if is_current_backend_wx():
+        for item in control.GetSizer().GetChildren():
+            button = item.GetWindow()
+            # Ignore empty buttons (assumption that they are invisible)
+            if button.value != "":
+                button_status.append(button.GetValue())
+
+    elif is_current_backend_qt4():
+        layout = control.layout()
+        for i in range(layout.count()):
+            button = layout.itemAt(i).widget()
+            button_status.append(button.isChecked())
+
+    else:
+        raise NotImplementedError()
+
+    return button_status
+
 # ######### Debug tools