Added Command Design Pattern

Author: Hyunk3l

Behavioral/Command/CommandInterface.php

@@ -0,0 +1,15 @@
+<?php
+
+namespace PhpDesignPatterns\Behavioral\Command;
+
+/**
+ * Interface CommandInterface
+ * @package PhpDesignPatterns\Behavioral\Command
+ */
+interface CommandInterface
+{
+    /**
+     * @return mixed
+     */
+    public function execute();
+}

Behavioral/Command/CommandInvoker.php

@@ -0,0 +1,39 @@
+<?php
+
+namespace PhpDesignPatterns\Behavioral\Command;
+
+/**
+ * Class CommandInvoker
+ * @package PhpDesignPatterns\Behavioral\Command
+ */
+class CommandInvoker
+{
+    /**
+     * Instance of CommandInterface.
+     *
+     * @var CommandInterface
+     */
+    private $command;
+
+    /**
+     * Set command dependency.
+     *
+     * @param CommandInterface $command
+     * @return CommandInvoker
+     */
+    public function setCommand(CommandInterface $command)
+    {
+        $this->command = $command;
+        return $this;
+    }
+
+    /**
+     * Run the command.
+     *
+     * @return mixed
+     */
+    public function run()
+    {
+        return $this->command->execute();
+    }
+}

Behavioral/Command/README.md

@@ -0,0 +1,7 @@
+# Command Design Pattern
+
+## Intent
+
+“Encapsulate a request as an object, thereby letting you parameterize clients with different requests, queue or log requests, and support undoable operations.”
+
+Excerpt From: Erich Gamma. “Design Patterns: Elements of Reusable Object-Oriented Software.”

Behavioral/Command/ReceiverInterface.php

@@ -0,0 +1,18 @@
+<?php
+
+namespace PhpDesignPatterns\Behavioral\Command;
+
+/**
+ * Interface ReceiverInterface
+ * @package PhpDesignPatterns\Behavioral\Command
+ */
+interface ReceiverInterface
+{
+    /**
+     * Execute a command.
+     *
+     * @param $command
+     * @return string
+     */
+    public function executeCommand($command);
+}

Behavioral/Command/SwitchButtonCommand.php

@@ -0,0 +1,37 @@
+<?php
+
+namespace PhpDesignPatterns\Behavioral\Command;
+
+/**
+ * Class SwitchButtonCommand
+ * @package PhpDesignPatterns\Behavioral\Command
+ */
+class SwitchButtonCommand implements CommandInterface
+{
+    /**
+     * Instance of ReceiverInterface.
+     *
+     * @var ReceiverInterface
+     */
+    private $control;
+
+    /**
+     * Class constructor.
+     *
+     * @param ReceiverInterface $control
+     */
+    public function __construct(ReceiverInterface $control)
+    {
+        $this->control = $control;
+    }
+
+    /**
+     * Execute the switch tv command.
+     *
+     * @return string
+     */
+    public function execute()
+    {
+        return $this->control->executeCommand("Tv has been switched on.");
+    }
+}

Behavioral/Command/TvControl.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace PhpDesignPatterns\Behavioral\Command;
+
+/**
+ * Class TvControl
+ * @package PhpDesignPatterns\Behavioral\Command
+ */
+class TvControl implements ReceiverInterface
+{
+    /**
+     * Execute the command in input.
+     *
+     * @param $command
+     * @return string
+     */
+    public function executeCommand($command)
+    {
+        /* Dummy implementation here. You would implement the logic to execute the command. */
+        return $command;
+    }
+}

Tests/Behavioral/Command/CommandInvokerTest.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace PhpDesignPatterns\Tests\Behavioral\Command;
+
+use PhpDesignPatterns\Behavioral\Command\CommandInvoker;
+
+/**
+ * Class CommandInvokerTest
+ * @package PhpDesignPatterns\Tests\Behavioral\Command
+ */
+class CommandInvokerTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Testing the command.
+     */
+    public function testCommand()
+    {
+        $command = $this->getMock('PhpDesignPatterns\\Behavioral\\Command\\CommandInterface', array('execute'));
+        $command
+            ->expects($this->once())
+            ->method('execute')
+            ->will($this->returnValue($expected_output = 'Dummy command!'))
+        ;
+        $invoker = new CommandInvoker;
+        $invoker->setCommand($command);
+        $this->assertEquals($expected_output, $invoker->run());
+    }
+}

Tests/Behavioral/Command/SwitchButtonCommandTest.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace PhpDesignPatterns\Tests\Behavioral\Command;
+
+use PhpDesignPatterns\Behavioral\Command\SwitchButtonCommand;
+
+/**
+ * Class SwitchButtonCommandTest
+ * @package PhpDesignPatterns\Tests\Behavioral\Command
+ */
+class SwitchButtonCommandTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Testing execute.
+     */
+    public function testExecuteCommand()
+    {
+        $receiver = $this->getMock("\\PhpDesignPatterns\\Behavioral\\Command\\ReceiverInterface", array("executeCommand"));
+        $receiver
+            ->expects($this->once())
+            ->method("executeCommand")
+            ->with("Tv has been switched on.")
+            ->will($this->returnValue("Tv has been switched on."))
+        ;
+        $command = new SwitchButtonCommand($receiver);
+        $this->assertEquals("Tv has been switched on.", $command->execute());
+    }
+}

Tests/Behavioral/Command/TvControlTest.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace PhpDesignPatterns\Tests\Behavioral\Command;
+
+use PhpDesignPatterns\Behavioral\Command\TvControl;
+
+/**
+ * Class TvControlTest
+ * @package PhpDesignPatterns\Tests\Behavioral\Command
+ */
+class TvControlTest extends \PHPUnit_Framework_TestCase
+{
+    /**
+     * Testing execute.
+     */
+    public function testExecuteCommand()
+    {
+        $control            = new TvControl;
+        $expected_command   = "dummy command.";
+        $this->assertEquals($expected_command, $control->executeCommand($expected_command));
+    }
+}