made a lot of changes to https://github.com/pantsbuild/pants/pull/6374, and was actually able to remove every

__new__

override beyond

JarDependency

and one other one that was too complex to replicate, by using the declarative type constraint factories

convert

,

convert_default

, and

optional

, and if you look at the diff you can see what that change looks like. there's also testing for everything