Test how the manager handles window changes

features/manager/change.feature

@@ -0,0 +1,7 @@
+Feature: clients window properties updating
+
+  Scenario: logs when the window properties of a client change
+    Given uhwm is running
+    And a window is mapped
+    When the window name changes to "testing_new_name"
+    Then the output must match /updat.+testing_new_name/i

features/steps/x_steps.rb

@@ -28,6 +28,10 @@ When /^the window is destroyed$/ do
   x_client.destroy.sync
 end
 
+When /^the window name changes to "([^"]+)"$/ do |name|
+  x_client.window_name = name
+end
+
 Then /^it must connect to X display$/ do
   uhwm_wait_ready
   expect(x_socket_check uhwm.pid).to be true