Merge branch 'events-key_press-quit'

Implement a few basic classes to handle different concerns (Runner,
Manager, Dispatcher) and integrate them together with a hard coded hook
for `mod1+q' key binding, which will initiate program termination.

.gitignore

@@ -1,2 +1,3 @@
 /Gemfile-custom.rb
 /Gemfile.lock
+/tmp/

bin/uhwm

@@ -3,4 +3,3 @@
 require 'uh/wm'
 
 Uh::WM::CLI.run(ARGV)
-sleep 8

features/actions/quit.feature

@@ -0,0 +1,6 @@
+Feature: quit action
+
+  Scenario: quits on keybing press
+    Given uhwm is running
+    When I press the default quit key binding
+    Then uhwm should terminate successfully

features/steps/run_steps.rb

@@ -4,6 +4,15 @@ def uhwm_run options = nil
   @interactive = @process = run command.join ' '
 end
 
+def uhwm_run_wait_ready
+  uhwm_run
+  uhwm_wait_output 'Connected to'
+end
+
+Given /^uhwm is running$/ do
+  uhwm_run_wait_ready
+end
+
 When /^I start uhwm$/ do
   uhwm_run
 end
@@ -15,3 +24,7 @@ end
 Then /^the exit status must be (\d+)$/ do |exit_status|
   assert_exit_status exit_status.to_i
 end
+
+Then /^uhwm should terminate successfully$/ do
+  assert_exit_status 0
+end

features/steps/x_steps.rb

@@ -1,3 +1,11 @@
+def x_key key
+  fail "cannot simulate X key `#{key}'" unless system "xdotool key #{key}"
+end
+
+When /^I press the default quit key binding$/ do
+  x_key 'alt+q'
+end
+
 Then /^it must connect to X display$/ do
   uhwm_wait_output 'Connected to'
   expect(`sockstat -u`.lines.grep /\s+ruby.+\s+#{@process.pid}/)

lib/uh/wm.rb

@@ -1,7 +1,10 @@
 require 'uh'
 
 require 'uh/wm/cli'
+require 'uh/wm/dispatcher'
 require 'uh/wm/env'
+require 'uh/wm/manager'
+require 'uh/wm/runner'
 
 module Uh
   module WM

lib/uh/wm/cli.rb

@@ -32,9 +32,7 @@ module Uh
       end
 
       def run
-        @display = Display.new
-        @display.open
-        @env.log "Connected to X server on `#{@display}'"
+        Runner.run env
       end
 
 

lib/uh/wm/dispatcher.rb

@@ -0,0 +1,31 @@
+module Uh
+  module WM
+    class Dispatcher
+      attr_reader :hooks
+
+      def initialize hooks = Hash.new
+        @hooks = hooks
+      end
+
+      def [] *key
+        @hooks[translate_key key] or []
+      end
+
+      def on *key, &block
+        @hooks[translate_key key] ||= []
+        @hooks[translate_key key] << block
+      end
+
+      def emit *key
+        @hooks[translate_key key].tap { |o| o.each { |e| e.call } if o }
+      end
+
+
+      private
+
+      def translate_key key
+        key.one? ? key[0] : key
+      end
+    end
+  end
+end

lib/uh/wm/manager.rb

@@ -0,0 +1,30 @@
+module Uh
+  module WM
+    class Manager
+      attr_reader :display
+
+      def initialize events, display = Display.new
+        @events   = events
+        @display  = display
+      end
+
+      def connect
+        @display.open
+      end
+
+      def grab_key keysym
+        @display.grab_key keysym.to_s, KEY_MODIFIERS[:mod1]
+      end
+
+      def handle_pending_events
+        handle @display.next_event while @display.pending?
+      end
+
+      def handle event
+        case event.type
+        when :key_press then @events.emit :key, event.key.to_sym
+        end
+      end
+    end
+  end
+end

lib/uh/wm/runner.rb

@@ -0,0 +1,52 @@
+module Uh
+  module WM
+    class Runner
+      class << self
+        def run env, **options
+          runner = new env, **options
+          runner.register_event_hooks
+          runner.connect_manager
+          runner.run_until { runner.stopped? }
+        end
+      end
+
+      attr_reader :env, :events, :manager
+
+      def initialize env, manager: nil, stopped: false
+        @env      = env
+        @events   = Dispatcher.new
+        @manager  = manager || Manager.new(@events)
+        @stopped  = stopped
+      end
+
+      def stopped?
+        !!@stopped
+      end
+
+      def stop!
+        @stopped = true
+      end
+
+      def register_event_hooks
+        register_key_bindings_hooks
+      end
+
+      def connect_manager
+        @manager.connect
+        @env.log "Connected to X server"
+        @manager.grab_key :q
+      end
+
+      def run_until &block
+        @manager.handle_pending_events until block.call
+      end
+
+
+      private
+
+      def register_key_bindings_hooks
+        @events.on(:key, :q) { stop! }
+      end
+    end
+  end
+end

spec/uh/wm/cli_spec.rb

@@ -15,6 +15,10 @@ module Uh
           described_class.run arguments, stdout: stdout, stderr: stderr
         end
 
+        # FIXME: remove this hack we currently need to prevent the Runner from
+        # blocking.
+        before { allow(Runner).to receive :run }
+
         it 'builds a new CLI with given arguments' do
           expect(described_class)
             .to receive(:new).with(arguments, stdout: stdout).and_call_original
@@ -63,19 +67,10 @@ module Uh
       end
 
       describe '#run' do
-        let(:display) { instance_spy Display }
-
-        before { allow(Display).to receive(:new) { display } }
-
-        it 'opens a new X display' do
-          expect(display).to receive :open
+        it 'runs a runner with the env' do
+          expect(Runner).to receive(:run).with(cli.env)
           cli.run
         end
-
-        it 'prints a message on standard output when connected' do
-          cli.run
-          expect(stdout.string).to match /connected/i
-        end
       end
 
       describe '#parse_arguments!' do

spec/uh/wm/dispatcher_spec.rb

@@ -0,0 +1,64 @@
+module Uh
+  module WM
+    RSpec.describe Dispatcher do
+      let(:hooks)           { {} }
+      subject(:dispatcher)  { described_class.new hooks }
+
+      describe '#[]' do
+        context 'when given key for existing hook' do
+          let(:hooks) { { hook_key: [:hook] } }
+
+          it 'returns registered hooks for this key' do
+            expect(dispatcher[:hook_key]).to eq [:hook]
+          end
+        end
+
+        context 'when given multiple keys for existing hook' do
+          let(:hooks) { { %i[hook key] => [:hook] } }
+
+          it 'returns registered hooks for this key' do
+            expect(dispatcher[:hook, :key]).to eq [:hook]
+          end
+        end
+
+        context 'when given key for unknown hook' do
+          it 'returns an empty array' do
+            expect(dispatcher[:unknown_hook]).to eq []
+          end
+        end
+      end
+
+      describe '#on' do
+        it 'registers given hook for given key' do
+          dispatcher.on(:hook_key) { :hook }
+          expect(dispatcher.hooks[:hook_key]).to be
+        end
+
+        it 'registers given hook for given multiple keys' do
+          dispatcher.on(:hook, :key) { :hook }
+          expect(dispatcher.hooks[%i[hook key]]).to be
+        end
+      end
+
+      describe '#emit' do
+        it 'calls hooks registered for given key' do
+          dispatcher.on(:hook_key) { throw :hook_code }
+          expect { dispatcher.emit :hook_key }.to throw_symbol :hook_code
+        end
+
+        context 'when no hooks are registered for given key' do
+          it 'does not call another hook' do
+            dispatcher.on(:hook_key) { throw :hook_code }
+            expect { dispatcher.emit :other_hook_key }.not_to throw_symbol
+          end
+        end
+
+        context 'when no hooks are registered at all' do
+          it 'does not raise any error' do
+            expect { dispatcher.emit :hook_key }.not_to raise_error
+          end
+        end
+      end
+    end
+  end
+end

spec/uh/wm/manager_spec.rb

@@ -0,0 +1,69 @@
+module Uh
+  module WM
+    RSpec.describe Manager do
+      let(:events)      { Dispatcher.new }
+      let(:display)     { Display.new }
+      subject(:manager) { described_class.new events, display }
+
+      describe '#initialize' do
+        it 'assigns a new display' do
+          expect(manager.display).to be_a Display
+        end
+      end
+
+      describe '#connect' do
+        it 'opens the display' do
+          expect(manager.display).to receive :open
+          manager.connect
+        end
+      end
+
+      describe '#grab_key' do
+        it 'grabs given key on the display' do
+          expect(manager.display)
+            .to receive(:grab_key).with('q', KEY_MODIFIERS[:mod1])
+          manager.grab_key :q
+        end
+      end
+
+      describe '#handle_pending_events' do
+        let(:event) { double 'event' }
+
+        context 'when an event is pending on display' do
+          before do
+            allow(display).to receive(:pending?).and_return true, false
+            allow(display).to receive(:next_event) { event }
+          end
+
+          it 'handles the event' do
+            expect(manager).to receive(:handle).with(event).once
+            manager.handle_pending_events
+          end
+        end
+
+        context 'when multiple events are pending on display' do
+          before do
+            allow(display).to receive(:pending?).and_return true, true, false
+            allow(display).to receive(:next_event) { event }
+          end
+
+          it 'handles all pending events' do
+            expect(manager).to receive(:handle).with(event).twice
+            manager.handle_pending_events
+          end
+        end
+      end
+
+      describe '#handle' do
+        context 'when key_release event is given' do
+          let(:event) { double 'event', type: :key_press, key: 'q' }
+
+          it 'emits :key event with the corresponding key' do
+            events.on(:key, :q) { throw :key_press_code }
+            expect { manager.handle event }.to throw_symbol :key_press_code
+          end
+        end
+      end
+    end
+  end
+end

spec/uh/wm/runner_spec.rb

@@ -0,0 +1,112 @@
+module Uh
+  module WM
+    RSpec.describe Runner do
+      let(:env)         { Env.new(StringIO.new) }
+      subject(:runner)  { described_class.new env }
+
+      describe '.run' do
+        subject(:run) { described_class.run env, stopped: true }
+
+        it 'builds a new Runner with given env' do
+          expect(described_class)
+            .to receive(:new).with(env, anything).and_call_original
+          run
+        end
+
+        it 'registers event hooks' do
+          runner.stop!
+          allow(described_class).to receive(:new) { runner }
+          expect(runner).to receive(:register_event_hooks)
+          run
+        end
+
+        it 'connects the manager' do
+          runner.stop!
+          allow(described_class).to receive(:new) { runner }
+          expect(runner).to receive(:connect_manager)
+          run
+        end
+      end
+
+      describe '#initialize' do
+        it 'assigns the env' do
+          expect(runner.env).to be env
+        end
+
+        it 'assigns a new Dispatcher' do
+          expect(runner.events).to be_a Dispatcher
+        end
+
+        it 'assigns a new Manager' do
+          expect(runner.manager).to be_a Manager
+        end
+
+        it 'is not stopped' do
+          expect(runner).not_to be_stopped
+        end
+      end
+
+      describe '#stopped?' do
+        context 'when not stopped' do
+          it 'returns false' do
+            expect(runner.stopped?).to be false
+          end
+        end
+
+        context 'when stopped' do
+          before { runner.stop! }
+
+          it 'returns true' do
+            expect(runner.stopped?).to be true
+          end
+        end
+      end
+
+      describe '#stop!' do
+        it 'sets the runner as stopped' do
+          expect { runner.stop! }
+            .to change { runner.stopped? }
+            .from(false).to(true)
+        end
+      end
+
+      describe '#register_event_hooks' do
+        context 'key bindings' do
+          it 'registers key bindings event hooks' do
+            runner.register_event_hooks
+            expect(runner.events[:key, :q]).not_to be_empty
+          end
+        end
+      end
+
+      describe '#connect_manager' do
+        let(:manager)     { instance_spy Manager }
+        subject(:runner)  { described_class.new env, manager: manager }
+
+        it 'connects the manager' do
+          expect(runner.manager).to receive :connect
+          runner.connect_manager
+        end
+
+        it 'logs a message when connected' do
+          expect(env).to receive(:log).with /connected/i
+          runner.connect_manager
+        end
+
+        it 'tells the manager to grab keys' do
+          expect(runner.manager).to receive(:grab_key).with :q
+          runner.connect_manager
+        end
+      end
+
+      describe '#run_until' do
+        it 'tells the manager to handle events until given block is true' do
+          block = proc { }
+          allow(block).to receive(:call).and_return(false, false, false, true)
+          expect(runner.manager).to receive(:handle_pending_events).exactly(3).times
+          runner.run_until &block
+        end
+      end
+    end
+  end
+end