- Check the parent file options for deprecation when deciding to tag Messages
and Enums as deprecated.
- Within the generated source push/pop the warning for implementing deprecated
things around a deprecated class implementation.
- Annotate the methods generated for extension fields as deprecated.
- Add a testing .proto file that covers deprecated fields, messages, enums,
enum values and compile it into the unittests to confirm things compile
cleanly.
- Add a testing .proto file that uses the file level option to make everything
deprecated and compile it into the unittests to confirm things compile
cleanly.
