Adding registrar classes to config files for easier registration of properties from modular code

application/Config/View.php

@@ -5,7 +5,7 @@ class View extends \CodeIgniter\Config\View
 	/**
 	 * When false, the view method will clear the data between each
 	 * call. This keeps your data safe and ensures there is no accidental
-	 * leaking between calls, so you would need to explicity pass the data
+	 * leaking between calls, so you would need to explicitly pass the data
 	 * to each view. You might prefer to have the data stick around between
 	 * calls so that it is available to all views. If that is the case,
 	 * set $saveData to true.

system/Config/BaseConfig.php

@@ -47,6 +47,14 @@
  */
 class BaseConfig
 {
+	/**
+	 * An optional array of classes that will act as Registrars
+	 * for rapidly setting config class properties.
+	 *
+	 * @var array
+	 */
+	protected $registrars;
+
 	/**
 	 * Will attempt to get environment variables with names
 	 * that match the properties of the child class.
@@ -87,6 +95,8 @@ class BaseConfig
 				}
 			}
 		}
+
+		$this->registerProperties();
 	}
 
 	//--------------------------------------------------------------------
@@ -118,4 +128,43 @@ class BaseConfig
 
 	//--------------------------------------------------------------------
 
+	/**
+	 * Provides external libraries a simple way to register one or more
+	 * options into a config file.
+	 */
+	protected function registerProperties()
+	{
+		if (empty($this->registrars)) return;
+
+		$shortName = (new \ReflectionClass($this))->getShortName();
+
+		// Check the registrar class for a method named after this class' shortName
+		foreach ($this->registrars as $callable)
+		{
+			if (! method_exists($callable, $shortName)) continue;
+
+			$properties = $callable::$shortName();
+
+			if (! is_array($properties))
+			{
+				throw new \RuntimeException('Registrars must return an array of properties and their values.');
+			}
+
+			foreach ($properties as $property => $value)
+			{
+				if (! property_exists($this, $property)) continue;
+
+				if (is_array($this->$property) && is_array($value))
+				{
+					$this->$property = array_merge($this->$property, $value);
+				}
+				else {
+					$this->$property = $value;
+				}
+			}
+		}
+	}
+
+	//--------------------------------------------------------------------
+
 }

system/Config/View.php

@@ -1,6 +1,6 @@
 <?php namespace CodeIgniter\Config;
 
-class View {
+class View extends BaseConfig {
 
 	protected $coreFilters = [
 		'abs'               => '\CodeIgniter\View\Filters::abs',
@@ -35,6 +35,8 @@ class View {
 	{
 	    $this->filters = array_merge($this->filters, $this->coreFilters);
 	    $this->plugins = array_merge($this->plugins, $this->corePlugins);
+
+	    parent::__construct();
 	}
 
 }

tests/_support/Config/Registrar.php

@@ -0,0 +1,17 @@
+<?php namespace Tests\Support\Config;
+
+/**
+ * Class Registrar
+ *
+ * Provides a basic registrar class for testing BaseConfig registration functions.
+ */
+class Registrar
+{
+	public static function RegistrarConfig()
+	{
+		return [
+			'bar' => ['first', 'second']
+		];
+	}
+
+}

tests/system/Config/BaseConfigTest.php

@@ -16,6 +16,10 @@ class BaseConfigTest extends CIUnitTestCase
 		{
 			require $this->fixturesFolder.'/SimpleConfig.php';
 		}
+		if (! class_exists('RegistrarConfig', false))
+		{
+			require $this->fixturesFolder.'/RegistrarConfig.php';
+		}
 	}
 
 	//--------------------------------------------------------------------
@@ -96,4 +100,11 @@ class BaseConfigTest extends CIUnitTestCase
 
 	//--------------------------------------------------------------------
 
+	public function testRegistrars()
+	{
+		$config = new \RegistrarConfig();
+
+		$this->assertEquals(['baz', 'first', 'second'], $config->bar);
+	}
+
 }

tests/system/Config/fixtures/RegistrarConfig.php

@@ -0,0 +1,13 @@
+<?php
+
+class RegistrarConfig extends \CodeIgniter\Config\BaseConfig
+{
+	public $foo = 'bar';
+	public $bar = [
+		'baz'
+	];
+
+	protected $registrars = [
+		\Tests\Support\Config\Registrar::class
+	];
+}