Migrate remaining failure messages to mypy.messages

I'm working on a tool to provide a more gradual mypy adoption path, by providing a fine grained configuration for selecting or ignoring mypy errors. My current prototype uses regular expressions, but maintaining a comprehensive set of regular expressions is both time consuming and brittle, as existing messages could change, and new ones will be added.

I noticed that an effort has already been made to move error messages from mypy.checkexpr into mypy.messages. Making this set of constants complete would solve my problem, and hopefully be of benefit to you all as well. Would you accept a pull request to migrate the remaining failure messages from checkexpr, semanal, semanal_newtype, and fastparse2 to messages constants?

まず、mypy.messages にある既存のメッセージ定数と、mypy.checkexpr からメッセージがどのように移行されたかを確認します。次に、mypy.checkexpr、mypy.semanal、mypy.semanal_newtype、mypy.fastparse2 にある失敗メッセージを調べます。これらのモジュールに残っている失敗メッセージが mypy.messages の定数を使用するようになれば完了です。