Tests added for #421

library/Requests/Utility/FilteredIterator.php

@@ -42,4 +42,20 @@ public function current() {
 		$value = call_user_func($this->callback, $value);
 		return $value;
 	}
+
+	/**
+	 * @inheritdoc
+	 */
+	public function unserialize( $serialized ) {
+	}
+
+	/**
+	 * @inheritdoc
+	 */
+	public function __unserialize( $serialized ) { // phpcs:ignore PHPCompatibility.FunctionNameRestrictions.ReservedFunctionNames.MethodDoubleUnderscore,PHPCompatibility.FunctionNameRestrictions.NewMagicMethods.__unserializeFound
+	}
+
+	public function __wakeup() { // phpcs:ignore PHPCompatibility.FunctionNameRestrictions.ReservedFunctionNames.MethodDoubleUnderscore,PHPCompatibility.FunctionNameRestrictions.NewMagicMethods.__wakeupFound
+		unset( $this->callback );
+	}
 }

tests/Utility/FilteredIterator.php

@@ -0,0 +1,32 @@
+<?php
+
+class RequestsTest_Requests extends PHPUnit_Framework_TestCase {
+	/**
+	 * @dataProvider data_serialize_deserialize_objects
+	 */
+	function test_deserialize_request_utility_filtered_iterator_objects( $value ) {
+		$serialized = serialize( $value );
+		if ( get_class( $value ) === 'Requests_Utility_FilteredIterator' ) {
+			$new_value = unserialize( $serialized );
+			if ( version_compare( PHP_VERSION, '5.3', '>=' ) ) {
+				$property = ( new ReflectionClass( 'Requests_Utility_FilteredIterator' ) )->getProperty( 'callback' );
+				$property->setAccessible( true );
+				$callback_value = $property->getValue( $new_value );
+				$this->assertSame( null, $callback_value );
+			} else {
+				$current_item = $new_value->current();
+				$this->assertSame( null, $current_item );
+			}
+		} else {
+			$this->assertEquals( $value->count(), unserialize( $serialized )->count() );
+		}
+	}
+
+	function data_serialize_deserialize_objects() {
+		return array(
+			array( new Requests_Utility_FilteredIterator( array( 1 ), 'md5' ) ),
+			array( new Requests_Utility_FilteredIterator( array( 1, 2 ), 'sha1' ) ),
+			array( new ArrayIterator( array( 1, 2, 3 ) ) ),
+		);
+	}
+}