Handle termination properly

* Tell the manager to close the display before terminating;
* Log about quit request and process termination.

spec/uh/wm/manager_spec.rb

@@ -1,6 +1,7 @@
 module Uh
   module WM
     RSpec.describe Manager do
+      let(:block)       { proc { } }
       let(:events)      { Dispatcher.new }
       let(:modifier)    { :mod1 }
       let(:display)     { Display.new }
@@ -11,8 +12,6 @@ module Uh
       end
 
       describe '#connect', :xvfb do
-        let(:block) { proc { } }
-
         it 'opens the display' do
           expect(manager.display).to receive(:open).and_call_original
           manager.connect
@@ -45,6 +44,20 @@ module Uh
         end
       end
 
+      describe '#disconnect' do
+        it 'closes the display' do
+          expect(display).to receive :close
+          manager.disconnect
+        end
+
+        it 'emits :disconnected event' do
+          allow(display).to receive :close
+          events.on :disconnected, &block
+          expect(block).to receive :call
+          manager.disconnect
+        end
+      end
+
       describe '#grab_key' do
         it 'grabs given key on the display' do
           expect(manager.display)

spec/uh/wm/runner_spec.rb

@@ -129,6 +129,19 @@ module Uh
           runner.run_until &block
         end
       end
+
+      describe '#terminate' do
+        it 'tells the manager to disconnect' do
+          expect(runner.manager).to receive :disconnect
+          runner.terminate
+        end
+
+        it 'logs about program termination' do
+          allow(runner.manager).to receive :disconnect
+          expect(env).to receive(:log).with /terminat/i
+          runner.terminate
+        end
+      end
     end
   end
 end