version bump: 1.0.0 -> (breaking) -> 2.0.0
error: breaking changes in `Abc`
 --> mix/new.rs:2:5
  |
2 |     pub enum Abc {}
  |     ^^^^^^^^^^^^
  |
  = warning: item kind changed (breaking)

error: breaking changes in `Def`
 --> mix/new.rs:3:5
  |
3 |     pub struct Def;
  |     ^^^^^^^^^^^^^^
  |
  = warning: item kind changed (breaking)

error: path changes to `Abc`
  --> mix/new.rs:2:5
   |
2  |     pub enum Abc {}
   |     ^^^^^^^^^^^^
   |
warning: removed path (breaking)
  --> mix/old.rs:10:9
   |
10 | pub use self::a::Abc;
   |         ^^^^^^^^^^^^
note: added path (technically breaking)
  --> mix/new.rs:7:13
   |
7  |     pub use a::Abc;
   |             ^^^^^^

warning: path changes to `Def`
  --> mix/new.rs:3:5
   |
3  |     pub struct Def;
   |     ^^^^^^^^^^^^^^
   |
note: added path (technically breaking)
  --> mix/new.rs:10:9
   |
10 | pub use self::a::Def;
   |         ^^^^^^^^^^^^

error: aborting due to 3 previous errors; 1 warning emitted