AppModel.php

<?php

...

	public function __construct($id = false, $table = null, $ds = null) {
		parent::__construct($id, $table, $ds);

		if ((PHP_SAPI !== 'cli' && !defined('CORE_TEST_CASES')) && get_class($this) === 'AppModel') {
			throw new \Exception(sprintf(
				'AppModel was initialized for "%s" (table "%s"), either the model doesn\'t exist or there is a reference to it using a different plugin.',
				$this->alias,
				$this->table
			));
		}
	}