yii2的老版本会有在PHP7运行的错误提示
Cannot use yii\base\Object as Object because ‘Object’ is a special class name
use yii\base\Object;
这里的Object 已经是PHP7的保留关键字，可以升级yii解决这个问题
执行
composer update
解决问题
Updating dependencies (including require-dev)
Package operations: 0 installs, 1 update, 0 removals
- Updating yiisoft/yii2 (2.0.15.1 => 2.0.42.1): Downloading (100%)
Package codeception/base is abandoned, you should avoid using it. No replacement was suggested.
Package fzaninotto/faker is abandoned, you should avoid using it. No replacement was suggested.
Package phpunit/php-token-stream is abandoned, you should avoid using it. No replacement was suggested.
Package phpunit/phpunit-mock-objects is abandoned, you should avoid using it. No replacement was suggested.
Writing lock file
Generating autoload files
1 package you are using is looking for funding.
Use the `composer fund` command to find out more!
Seems you have upgraded Yii Framework from version 2.0.15.1 to 2.0.42.1.
Please check the upgrade notes for possible incompatible changes
and adjust your application code accordingly.
The relevant notes for your upgrade are too long to be displayed here.
You can find the upgrade notes for all versions online at:
https://github.com/yiisoft/yii2/blob/2.0.42.1/framework/UPGRADE.md
