Error in Generators

I have a similar problem with https://github.com/Codeception/AspectMock/pull/66

When i try to mock laravel database (v5.2.45) file [/vendor/illuminate/database/Query/Builder.php](https://github.com/illuminate/database/blob/v5.2.45/Query/Builder.php#L1737)

`
/**
* Get a generator for the given query.
*
* @return \Generator
*/
public function cursor()
{
if (is_null($this->columns)) {
$this->columns = ['*'];
}
return $this->connection->cursor(
$this->toSql(), $this->getBindings(), ! $this->useWritePdo
);
}
`
Something goes wrong with this function, and tests fails with

> PHP Fatal error: Generators cannot return values using "return" in /www/backend/vendor/illuminate/database/Query/Builder.php on line 1750

How can I fix this?

从 vendor/illuminate/database/Query/Builder.php 中 Laravel v5.2.45 的实现开始，尤其关注 cursor()，并对比 Codeception/AspectMock pull request 66 中描述的行为。复现失败的测试，并确定 AspectMock 是否与此生成器不兼容；当所报告的 Laravel 数据库案例不再出现 fatal error 时，即视为完成。

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