Networks and Sites: Set WP_Network properties via setters upon creation.

This ensures that `WP_Network::$id` is stored internally as `int`, to match the documented type.

Follow-up to [37870].

Props ironprogrammer, scottculverhouse, spacedmonkey, SergeyBiryukov.
See #62035.

git-svn-id: https://develop.svn.wordpress.org/trunk@59020 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-includes/class-wp-network.php

@@ -131,7 +131,7 @@ public static function get_instance( $network_id ) {
 	 */
 	public function __construct( $network ) {
 		foreach ( get_object_vars( $network ) as $key => $value ) {
-			$this->$key = $value;
+			$this->__set( $key, $value );
 		}
 
 		$this->_set_site_name();

tests/phpunit/tests/multisite/network.php

@@ -127,6 +127,8 @@ public function get_main_network_id() {
 
 		/**
 		 * @ticket 37050
+		 *
+		 * @covers WP_Network::__get
 		 */
 		public function test_wp_network_object_id_property_is_int() {
 			$id = self::factory()->network->create();
@@ -136,6 +138,28 @@ public function test_wp_network_object_id_property_is_int() {
 			$this->assertSame( (int) $id, $network->id );
 		}
 
+		/**
+		 * Tests that the `WP_Network::$id` property is stored as int.
+		 *
+		 * Uses reflection to access the private property.
+		 * Differs from using the public getter method, which casts to int.
+		 *
+		 * @ticket 62035
+		 *
+		 * @covers WP_Network::__construct
+		 */
+		public function test_wp_network_object_id_property_stored_as_int() {
+			$id = self::factory()->network->create();
+
+			$network = WP_Network::get_instance( $id );
+
+			$reflection = new ReflectionObject( $network );
+			$property   = $reflection->getProperty( 'id' );
+			$property->setAccessible( true );
+
+			$this->assertSame( (int) $id, $property->getValue( $network ) );
+		}
+
 		/**
 		 * @ticket 22917
 		 */