PHP7 TemplateMethod

Behavioral/TemplateMethod/BeachJourney.php

@@ -2,16 +2,10 @@
 
 namespace DesignPatterns\Behavioral\TemplateMethod;
 
-/**
- * BeachJourney is vacation at the beach.
- */
 class BeachJourney extends Journey
 {
-    /**
+    protected function enjoyVacation(): string
-     * prints what to do to enjoy your vacation.
-     */
-    protected function enjoyVacation()
     {
-        echo "Swimming and sun-bathing\n";
+        return "Swimming and sun-bathing";
     }
 }

Behavioral/TemplateMethod/CityJourney.php

@@ -2,16 +2,15 @@
 
 namespace DesignPatterns\Behavioral\TemplateMethod;
 
-/**
- * CityJourney is a journey in a city.
- */
 class CityJourney extends Journey
 {
-    /**
+    protected function enjoyVacation(): string
-     * prints what to do in your journey to enjoy vacation.
-     */
-    protected function enjoyVacation()
     {
-        echo "Eat, drink, take photos and sleep\n";
+        return "Eat, drink, take photos and sleep";
+    }
+
+    protected function buyGift(): string
+    {
+        return "Buy a gift";
     }
 }

Behavioral/TemplateMethod/Journey.php

@@ -4,6 +4,11 @@ namespace DesignPatterns\Behavioral\TemplateMethod;
 
 abstract class Journey
 {
+    /**
+     * @var string[]
+     */
+    private $thingsToDo = [];
+
     /**
      * This is the public service provided by this class and its subclasses.
      * Notice it is final to "freeze" the global behavior of algorithm.
@@ -12,46 +17,49 @@ abstract class Journey
      */
     final public function takeATrip()
     {
-        $this->buyAFlight();
+        $this->thingsToDo[] = $this->buyAFlight();
-        $this->takePlane();
+        $this->thingsToDo[] = $this->takePlane();
-        $this->enjoyVacation();
+        $this->thingsToDo[] = $this->enjoyVacation();
-        $this->buyGift();
+        $buyGift = $this->buyGift();
-        $this->takePlane();
+
+        if ($buyGift !== null) {
+            $this->thingsToDo[] = $buyGift;
+        }
+
+        $this->thingsToDo[] = $this->takePlane();
     }
 
     /**
      * This method must be implemented, this is the key-feature of this pattern.
      */
-    abstract protected function enjoyVacation();
+    abstract protected function enjoyVacation(): string;
 
     /**
      * This method is also part of the algorithm but it is optional.
-     * This is an "adapter" (do not confuse with the Adapter pattern, not related)
+     * You can override it only if you need to
-     * You can override it only if you need to.
+     *
+     * @return null|string
      */
     protected function buyGift()
     {
+        return null;
+    }
+
+    private function buyAFlight(): string
+    {
+        return 'Buy a flight ticket';
+    }
+
+    private function takePlane(): string
+    {
+        return 'Taking the plane';
     }
 
     /**
-     * This method will be unknown by subclasses (better).
+     * @return string[]
      */
-    private function buyAFlight()
+    public function getThingsToDo(): array
     {
-        echo "Buying a flight\n";
+        return $this->thingsToDo;
     }
-
-    /**
-     * Subclasses will get access to this method but cannot override it and
-     * compromise this algorithm (warning : cause of cyclic dependencies).
-     */
-    final protected function takePlane()
-    {
-        echo "Taking the plane\n";
-    }
-
-    // A note regarding the keyword "final" : don't use it when you start coding :
-    // add it after you narrow and know exactly what change and what remain unchanged
-    // in this algorithm.
-    // [abstract] x [3 access] x [final] = 12 combinations, it can be hard !
 }

Behavioral/TemplateMethod/Tests/JourneyTest.php

@@ -4,40 +4,33 @@ namespace DesignPatterns\Behavioral\TemplateMethod\Tests;
 
 use DesignPatterns\Behavioral\TemplateMethod;
 
-/**
- * JourneyTest tests all journeys.
- */
 class JourneyTest extends \PHPUnit_Framework_TestCase
 {
-    public function testBeach()
+    public function testCanGetOnVacationOnTheBeach()
     {
-        $journey = new TemplateMethod\BeachJourney();
+        $beachJourney = new TemplateMethod\BeachJourney();
-        $this->expectOutputRegex('#sun-bathing#');
+        $beachJourney->takeATrip();
-        $journey->takeATrip();
+
+        $this->assertEquals(
+            ['Buy a flight ticket', 'Taking the plane', 'Swimming and sun-bathing', 'Taking the plane'],
+            $beachJourney->getThingsToDo()
+        );
     }
 
-    public function testCity()
+    public function testCanGetOnAJourneyToACity()
     {
-        $journey = new TemplateMethod\CityJourney();
+        $beachJourney = new TemplateMethod\CityJourney();
-        $this->expectOutputRegex('#drink#');
+        $beachJourney->takeATrip();
-        $journey->takeATrip();
-    }
 
-    /**
+        $this->assertEquals(
-     * How to test an abstract template method with PHPUnit.
+            [
-     */
+                'Buy a flight ticket',
-    public function testLasVegas()
+                'Taking the plane',
-    {
+                'Eat, drink, take photos and sleep',
-        $journey = $this->getMockForAbstractClass('DesignPatterns\Behavioral\TemplateMethod\Journey');
+                'Buy a gift',
-        $journey->expects($this->once())
+                'Taking the plane'
-            ->method('enjoyVacation')
+            ],
-            ->will($this->returnCallback(array($this, 'mockUpVacation')));
+            $beachJourney->getThingsToDo()
-        $this->expectOutputRegex('#Las Vegas#');
+        );
-        $journey->takeATrip();
-    }
-
-    public function mockUpVacation()
-    {
-        echo "Fear and loathing in Las Vegas\n";
     }
 }

Behavioral/TemplateMethod/uml/TemplateMethod.uml

@@ -3,24 +3,24 @@
   <ID>PHP</ID>
   <OriginalElement>\DesignPatterns\Behavioral\TemplateMethod\BeachJourney</OriginalElement>
   <nodes>
-    <node x="152.0" y="177.0">\DesignPatterns\Behavioral\TemplateMethod\CityJourney</node>
+    <node x="-18.0" y="234.0">\DesignPatterns\Behavioral\TemplateMethod\BeachJourney</node>
-    <node x="47.0" y="0.0">\DesignPatterns\Behavioral\TemplateMethod\Journey</node>
+    <node x="13.0" y="-3.0">\DesignPatterns\Behavioral\TemplateMethod\Journey</node>
-    <node x="0.0" y="177.0">\DesignPatterns\Behavioral\TemplateMethod\BeachJourney</node>
+    <node x="151.0" y="234.0">\DesignPatterns\Behavioral\TemplateMethod\CityJourney</node>
   </nodes>
   <notes />
   <edges>
-    <edge source="\DesignPatterns\Behavioral\TemplateMethod\CityJourney" target="\DesignPatterns\Behavioral\TemplateMethod\Journey">
-      <point x="0.0" y="-23.5" />
-      <point x="218.0" y="152.0" />
-      <point x="189.5" y="152.0" />
-      <point x="47.5" y="63.5" />
-    </edge>
     <edge source="\DesignPatterns\Behavioral\TemplateMethod\BeachJourney" target="\DesignPatterns\Behavioral\TemplateMethod\Journey">
       <point x="0.0" y="-23.5" />
       <point x="66.0" y="152.0" />
       <point x="94.5" y="152.0" />
       <point x="-47.5" y="63.5" />
     </edge>
+    <edge source="\DesignPatterns\Behavioral\TemplateMethod\CityJourney" target="\DesignPatterns\Behavioral\TemplateMethod\Journey">
+      <point x="0.0" y="-23.5" />
+      <point x="218.0" y="152.0" />
+      <point x="189.5" y="152.0" />
+      <point x="47.5" y="63.5" />
+    </edge>
   </edges>
   <settings layout="Hierarchic Group" zoom="1.0" x="142.0" y="112.0" />
   <SelectedNodes />