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diff --git a/includes/libs/ObjectFactory.php b/includes/libs/ObjectFactory.php
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+<?php
+/**
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
+
+/**
+ * Construct objects from configuration instructions.
+ *
+ * @author Bryan Davis <bd808@wikimedia.org>
+ * @copyright © 2014 Bryan Davis and Wikimedia Foundation.
+ */
+class ObjectFactory {
+
+	/**
+	 * Instantiate an object based on a specification array.
+	 *
+	 * The specification array must contain a 'class' key with string value
+	 * that specifies the class name to instantiate or a 'factory' key with
+	 * a callable (is_callable() === true). It can optionally contain
+	 * an 'args' key that provides arguments to pass to the
+	 * constructor/callable.
+	 *
+	 * Object construction using a specification having both 'class' and
+	 * 'args' members will call the constructor of the class using
+	 * ReflectionClass::newInstanceArgs. The use of ReflectionClass carries
+	 * a performance penalty and should not be used to create large numbers of
+	 * objects. If this is needed, consider introducing a factory method that
+	 * can be called via call_user_func_array() instead.
+	 *
+	 * Values in the arguments collection which are Closure instances will be
+	 * expanded by invoking them with no arguments before passing the
+	 * resulting value on to the constructor/callable. This can be used to
+	 * pass DatabaseBase instances or other live objects to the
+	 * constructor/callable. This behavior can be suppressed by adding
+	 * closure_expansion => false to the specification.
+	 *
+	 * @param array $spec Object specification
+	 * @return object
+	 * @throws InvalidArgumentException when object specification does not
+	 * contain 'class' or 'factory' keys
+	 * @throws ReflectionException when 'args' are supplied and 'class'
+	 * constructor is non-public or non-existent
+	 */
+	public static function getObjectFromSpec( $spec ) {
+		$args = isset( $spec['args'] ) ? $spec['args'] : array();
+
+		if ( !isset( $spec['closure_expansion'] ) ||
+			$spec['closure_expansion'] === true
+		) {
+			$args = array_map( function ( $value ) {
+				if ( is_object( $value ) && $value instanceof Closure ) {
+					// If an argument is a Closure, call it.
+					return $value();
+				} else {
+					return $value;
+				}
+			}, $args );
+		}
+
+		if ( isset( $spec['class'] ) ) {
+			$clazz = $spec['class'];
+			if ( !$args ) {
+				$obj = new $clazz();
+			} else {
+				$ref = new ReflectionClass( $clazz );
+				$obj = $ref->newInstanceArgs( $args );
+			}
+		} elseif ( isset( $spec['factory'] ) ) {
+			$obj = call_user_func_array( $spec['factory'], $args );
+		} else {
+			throw new InvalidArgumentException(
+				'Provided specification lacks both factory and class parameters.'
+			);
+		}
+
+		return $obj;
+	}
+}