Added Decorator and observer Patterns along with UnitTest for Observer

.idea/laravel-idea.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="InertiaPackage">
+    <option name="directoryPaths">
+      <list />
+    </option>
+  </component>
+</project>

.idea/patterns.iml

@@ -3,6 +3,7 @@
   <component name="NewModuleRootManager">
     <content url="file://$MODULE_DIR$">
       <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/tests" isTestSource="true" packagePrefix="App\Tests\" />
       <excludeFolder url="file://$MODULE_DIR$/vendor/clue/ndjson-react" />
       <excludeFolder url="file://$MODULE_DIR$/vendor/composer" />
       <excludeFolder url="file://$MODULE_DIR$/vendor/evenement/evenement" />
@@ -36,6 +37,30 @@
       <excludeFolder url="file://$MODULE_DIR$/vendor/symfony/service-contracts" />
       <excludeFolder url="file://$MODULE_DIR$/vendor/symfony/stopwatch" />
       <excludeFolder url="file://$MODULE_DIR$/vendor/symfony/string" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/myclabs/deep-copy" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/nikic/php-parser" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phar-io/manifest" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phar-io/version" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phpunit/php-code-coverage" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phpunit/php-file-iterator" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phpunit/php-invoker" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phpunit/php-text-template" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phpunit/php-timer" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/phpunit/phpunit" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/cli-parser" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/comparator" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/complexity" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/environment" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/exporter" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/global-state" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/lines-of-code" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/object-enumerator" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/object-reflector" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/recursion-context" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/type" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/sebastian/version" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/staabm/side-effects-detector" />
+      <excludeFolder url="file://$MODULE_DIR$/vendor/theseer/tokenizer" />
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />

.idea/php.xml

@@ -71,6 +71,30 @@
       <path value="$PROJECT_DIR$/vendor/friendsofphp/php-cs-fixer" />
       <path value="$PROJECT_DIR$/vendor/react/stream" />
       <path value="$PROJECT_DIR$/vendor/fidry/cpu-core-counter" />
+      <path value="$PROJECT_DIR$/vendor/nikic/php-parser" />
+      <path value="$PROJECT_DIR$/vendor/myclabs/deep-copy" />
+      <path value="$PROJECT_DIR$/vendor/phar-io/manifest" />
+      <path value="$PROJECT_DIR$/vendor/phar-io/version" />
+      <path value="$PROJECT_DIR$/vendor/staabm/side-effects-detector" />
+      <path value="$PROJECT_DIR$/vendor/theseer/tokenizer" />
+      <path value="$PROJECT_DIR$/vendor/phpunit/php-code-coverage" />
+      <path value="$PROJECT_DIR$/vendor/phpunit/php-file-iterator" />
+      <path value="$PROJECT_DIR$/vendor/phpunit/php-invoker" />
+      <path value="$PROJECT_DIR$/vendor/phpunit/php-text-template" />
+      <path value="$PROJECT_DIR$/vendor/phpunit/php-timer" />
+      <path value="$PROJECT_DIR$/vendor/phpunit/phpunit" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/global-state" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/complexity" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/recursion-context" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/object-enumerator" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/object-reflector" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/cli-parser" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/lines-of-code" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/type" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/version" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/comparator" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/exporter" />
+      <path value="$PROJECT_DIR$/vendor/sebastian/environment" />
     </include_path>
   </component>
   <component name="PhpProjectSharedConfiguration" php_language_level="8.3" />
@@ -82,6 +106,11 @@
   <component name="PhpStanOptionsConfiguration">
     <option name="transferred" value="true" />
   </component>
+  <component name="PhpUnit">
+    <phpunit_settings>
+      <PhpUnitSettings custom_loader_path="$PROJECT_DIR$/vendor/autoload.php" />
+    </phpunit_settings>
+  </component>
   <component name="Psalm">
     <Psalm_settings>
       <psalm_fixer_by_interpreter asDefaultInterpreter="true" interpreter_id="6adcaaf8-6d8b-41cc-8523-d95f7e166ea1" timeout="60000" />

.idea/phpspec.xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="PHPSpec">
+    <suites>
+      <PhpSpecSuiteConfiguration>
+        <option name="myPath" value="$PROJECT_DIR$" />
+      </PhpSpecSuiteConfiguration>
+    </suites>
+  </component>
+</project>

code/decorator.php

@@ -9,4 +9,9 @@
 
 declare(strict_types = 1);
 
-dump('Decorator');
+use Pattern\Structural\Decorator\{BasicInspection, OilChange, TireRotation};
+
+$service = new TireRotation(new OilChange(new BasicInspection()));
+
+echo $service->getDescription() . ': $';
+echo $service->getCost();

composer.json

@@ -5,6 +5,11 @@
       "": "src/"
     }
   },
+  "autoload-dev": {
+    "psr-4": {
+      "App\\Tests\\": "tests/"
+    }
+  },
   "authors": [
     {
       "name": "Yevhen Odynets",
@@ -16,7 +21,8 @@
     "ext-simplexml": "*"
   },
   "require-dev": {
-    "friendsofphp/php-cs-fixer": "^3.76"
+    "friendsofphp/php-cs-fixer": "^3.76",
+    "phpunit/phpunit": "^12.2"
   },
   "scripts": {
     "cs": "php-cs-fixer --config=./.php-cs-fixer.php check -v",

src/Pattern/Behavioral/Observer/User.php

@@ -0,0 +1,83 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 13:55
+ */
+
+declare(strict_types = 1);
+
+namespace Pattern\Behavioral\Observer;
+
+use SplObjectStorage;
+use SplObserver;
+use SplSubject;
+
+class User implements SplSubject
+{
+    /**
+     * @var string
+     */
+    private string $name;
+
+    /**
+     * @var SplObjectStorage
+     */
+    private SplObjectStorage $observers;
+
+    public function __construct()
+    {
+        $this->observers = new SplObjectStorage();
+    }
+
+    /**
+     * Attach an observer
+     */
+    public function attach(SplObserver $observer): void
+    {
+        $this->observers->attach($observer);
+    }
+
+    /**
+     * Detach an observer
+     */
+    public function detach(SplObserver $observer): void
+    {
+        $this->observers->detach($observer);
+    }
+
+    /**
+     * @return string
+     */
+    public function getName(): string
+    {
+        return $this->name;
+    }
+
+    /**
+     * @param  string  $name
+     *
+     * @return void
+     */
+    public function setName(string $name): void
+    {
+        $this->name = $name;
+
+        $this->notify();
+    }
+
+    /**
+     * Notify an observer
+     */
+    public function notify(): void
+    {
+        /** @var SplObserver $observer */
+        foreach ($this->observers as $observer) {
+            var_dump($observer);
+            $observer->update($this);
+        }
+    }
+
+}

src/Pattern/Behavioral/Observer/UserObserver.php

@@ -0,0 +1,31 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 14:06
+ */
+
+declare(strict_types = 1);
+
+namespace Pattern\Behavioral\Observer;
+
+use SplObserver;
+use SplSubject;
+
+class UserObserver implements SplObserver
+{
+    private array $namesLog = [];
+
+    public function update(SplSubject $subject): void
+    {
+        /** @var User $subject */
+        $this->namesLog[] = $subject->getName();
+    }
+
+    public function getNamesLog(): array
+    {
+        return $this->namesLog;
+    }
+}

src/Pattern/Structural/Decorator/BasicInspection.php

@@ -0,0 +1,25 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 11:38
+ */
+
+declare(strict_types = 1);
+
+namespace Pattern\Structural\Decorator;
+
+class BasicInspection implements CarServiceInterface
+{
+    public function getCost(): float
+    {
+        return 25.14;
+    }
+
+    public function getDescription(): string
+    {
+        return 'Basic inspection';
+    }
+}

src/Pattern/Structural/Decorator/BorderDecorator.php

@@ -1,22 +0,0 @@
-<?php
-
-/**
- * @package: patterns
- * @author: Yevhen Odynets
- * @date: 2025-07-04
- * @time: 10:42
- */
-
-declare(strict_types = 1);
-
-namespace Pattern\Structural\Decorator;
-
-class BorderDecorator implements ShapeInterface
-{
-    public function __construct(private ShapeInterface $shape) {}
-
-    public function draw(): void
-    {
-        echo '<div style="width: 8rem; height: 8rem; border: .5rem solid orange"></div>';
-    }
-}

src/Pattern/Structural/Decorator/CarServiceInterface.php

@@ -0,0 +1,19 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 11:53
+ */
+
+declare(strict_types = 1);
+
+namespace Pattern\Structural\Decorator;
+
+interface CarServiceInterface
+{
+    public function getCost(): float;
+
+    public function getDescription(): string;
+}

src/Pattern/Structural/Decorator/Circle.php

@@ -1,20 +0,0 @@
-<?php
-
-/**
- * @package: patterns
- * @author: Yevhen Odynets
- * @date: 2025-07-04
- * @time: 10:41
- */
-
-declare(strict_types = 1);
-
-namespace Pattern\Structural\Decorator;
-
-class Circle implements ShapeInterface
-{
-    public function draw(): void
-    {
-        // TODO: Implement draw() method.
-    }
-}

src/Pattern/Structural/Decorator/EmailDecorator.php

@@ -1,22 +0,0 @@
-<?php
-
-/**
- * @package: patterns
- * @author: Yevhen Odynets
- * @date: 2025-07-04
- * @time: 10:43
- */
-
-declare(strict_types = 1);
-
-namespace Pattern\Structural\Decorator;
-
-class EmailDecorator implements ShapeInterface
-{
-    public function __construct(private ShapeInterface $shape) {}
-
-    public function draw(): void
-    {
-        // TODO: Implement draw() method.
-    }
-}

src/Pattern/Structural/Decorator/OilChange.php

@@ -0,0 +1,27 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 12:08
+ */
+
+declare(strict_types = 1);
+
+namespace Pattern\Structural\Decorator;
+
+class OilChange implements CarServiceInterface
+{
+    public function __construct(protected CarServiceInterface $carService) {}
+
+    public function getCost(): float
+    {
+        return 29.89 + $this->carService->getCost();
+    }
+
+    public function getDescription(): string
+    {
+        return $this->carService->getDescription() . ', and oil change';
+    }
+}

src/Pattern/Structural/Decorator/ShapeInterface.php

@@ -1,17 +0,0 @@
-<?php
-
-/**
- * @package: patterns
- * @author: Yevhen Odynets
- * @date: 2025-07-04
- * @time: 10:38
- */
-
-declare(strict_types = 1);
-
-namespace Pattern\Structural\Decorator;
-
-interface ShapeInterface
-{
-    public function draw(): void;
-}

src/Pattern/Structural/Decorator/SmileDecorator.php

@@ -1,22 +0,0 @@
-<?php
-
-/**
- * @package: patterns
- * @author: Yevhen Odynets
- * @date: 2025-07-04
- * @time: 10:47
- */
-
-declare(strict_types = 1);
-
-namespace Pattern\Structural\Decorator;
-
-class SmileDecorator implements ShapeInterface
-{
-    public function __construct(private ShapeInterface $shape) {}
-
-    public function draw(): void
-    {
-        // TODO: Implement draw() method.
-    }
-}

src/Pattern/Structural/Decorator/Square.php

@@ -1,20 +0,0 @@
-<?php
-
-/**
- * @package: patterns
- * @author: Yevhen Odynets
- * @date: 2025-07-04
- * @time: 10:41
- */
-
-declare(strict_types = 1);
-
-namespace Pattern\Structural\Decorator;
-
-class Square implements ShapeInterface
-{
-    public function draw(): void
-    {
-        // TODO: Implement draw() method.
-    }
-}

src/Pattern/Structural/Decorator/TireRotation.php

@@ -0,0 +1,26 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 12:41
+ */
+
+declare(strict_types = 1);
+namespace Pattern\Structural\Decorator;
+
+class TireRotation implements CarServiceInterface
+{
+    public function __construct(protected CarServiceInterface $carService) {}
+
+    public function getCost(): float
+    {
+        return 25.14 + $this->carService->getCost();
+    }
+
+    public function getDescription(): string
+    {
+        return $this->carService->getDescription() . ', and tire rotation';
+    }
+}

tests/ObserverTest.php

@@ -0,0 +1,43 @@
+<?php
+
+/**
+ * @package: patterns
+ * @author: Yevhen Odynets
+ * @date: 2025-07-06
+ * @time: 13:31
+ */
+
+declare(strict_types = 1);
+
+namespace App\Tests;
+
+use Pattern\Behavioral\Observer\User;
+use Pattern\Behavioral\Observer\UserObserver;
+use PHPUnit\Framework\TestCase;
+
+class ObserverTest extends TestCase
+{
+    public function testObserver(): void
+    {
+        $user = new User();
+
+        /** These names will be skipped and not be added to the log of names */
+        $user->setName("Just a name");
+        $user->setName("Some new name");
+
+        $userObserver = new UserObserver();
+        $user->attach($userObserver);
+
+        /** After creating a new instance of UserObserver::class
+         * and attached it to User::class instance,
+         * these names will be added to the log of names */
+        $user->setName("Another new name");
+        $user->setName("Once again new name");
+        $user->setName("Possibly other new name");
+
+        $this->assertEquals(
+            ["Another new name", "Once again new name", "Possibly other new name"],
+            $userObserver->getNamesLog()
+        );
+    }
+}