Mill 2.0 API changes

Loose and completely non-committal list of changes for Mill 2.x, that can’t be applied before 2.x, because they would break either current behavior or binary compatibility.

Build Changes

• Don’t generate static forwarders for methods in objects. Instead, use the @static annotation to explicitly mark methods meant to be static.

  • scalac option: -Xno-forwarders

  • https://github.com/com-lihaoyi/mill/pull/5521#issuecomment-3296306218

Cleanups

• Remove deprecated API

  • Use sites of @deprecated annotation

  • Use sites of @unroll annotation

  • Search for "deprecated", "bin-compat", "shim", "TODO", "FIXME"

• Explicit code locations:

  • ❏ VisualizeModule.classpath

  • ❏ CoursierModule.repositoryTask0

  • ❏ JavaModule.coursierDependency and JavaModule.coursierDependency0

  • ❏ JavaModule.coursierProject0

• Remove binary-compatibility shims and compatibility workarounds (often their names end with 0)

API Changes

• Use a path-aware type for configuration data: https://github.com/com-lihaoyi/mill/pull/6129

Internal changes

• In Module traits, generate super-stubs for all inherited tasks, so overriding tasks at a later point is not a binary breaking change due to the missing super-stub.

  • Discussion: Improve binary-compatible Task overriding