public function switch_to_user( $user_id ) {
		$user_id = $this->getUserIdFromLogin( $user_id );

		PHPUnit_Framework_Assert::assertNotEmpty( $user_id );

		$this->visitPath( sprintf( 'wp-admin/user-edit.php?user_id=%d', $user_id ) );
		$this->getSession()->getPage()->clickLink( "Switch\xc2\xa0To" );
	}