--warn-annotation-comments

I think having a linter option warning about old-style type comment annotations, instead of PEP 3107/526 annotations, would be useful. (With the obvious exception of # type: ignore comments.) This is potentially something that would make more sense in linters like flake8, but mypy also feels like a natural place where such an option could exist.

未指定文件、测试或入口点。首先定位 mypy 的命令行选项处理，以及其对类型注释和 PEP 3107/526 注解的处理。完成标准是：为旧式类型注释注解提供可配置的警告，同时排除 # type: ignore，并配有覆盖该警告行为的测试。