bump mima previos version to 2.0.0

[julien-truffaut]

I am trying to verify binary compatibility for #794

I don't understand why mima reports lost of changes in monocle.std.nev. As far as I can tell, we haven't changed that file: v2.0.0...master

here is an example:

[error]  * method vectorToNev()monocle.PPrism in object monocle.std.nev has a different signature in current version, where it is <A:Ljava/lang/Object;>()Lmonocle/PPrism<Lscala/collection/immutable/Vector<TA;>;Lscala/collection/immutable/Vector<TA;>;Lcats/data/NonEmptyVector<TA;>;Lcats/data/NonEmptyVector<TA;>;>; rather than <A:Ljava/lang/Object;>()Lmonocle/PPrism<Lscala/collection/immutable/Vector<TA;>;Lscala/collection/immutable/Vector<TA;>;Lscala/collection/immutable/Vector<TA;>;Lscala/collection/immutable/Vector<TA;>;>;
[error]    filter with: ProblemFilters.exclude[IncompatibleSignatureProblem]("monocle.std.nev.vectorToNev")

[travisbrown]

I've seen this before. The problem is that Scala 2.13.1 is boxing the value class for some weird reason, while 2.13.0 didn't:

sbt:monocle> ++2.13.0
[info] Setting Scala version to 2.13.0 on 22 projects.
[info] Reapplying settings...
[info] Set current project to monocle (in build file:/home/travis/code/projects/Monocle/)
sbt:monocle> coreJVM/mimaReportBinaryIssues
[info] Updating coreJVM...
[info] Done updating.
[info] Compiling 86 Scala sources to /home/travis/code/projects/Monocle/core/jvm/target/scala-2.13/classes ...
[info] Done compiling.
[success] Total time: 12 s, completed Jan 9, 2020 10:04:27 AM

But:

sbt:monocle> ++2.13.1
[info] Setting Scala version to 2.13.1 on 22 projects.
[info] Reapplying settings...
[info] Set current project to monocle (in build file:/home/travis/code/projects/Monocle/)
sbt:monocle> coreJVM/mimaReportBinaryIssues
[info] Updating coreJVM...
[info] Done updating.
[info] Compiling 86 Scala sources to /home/travis/code/projects/Monocle/core/jvm/target/scala-2.13/classes ...
[info] Done compiling.
[error]  * method pNevToOneAnd()monocle.PIso in object monocle.Monocle has a different signature in current version, where it is <A:Ljava/lang/Object;B:Ljava/lang/Object;>()Lmonocle/PIso<Lcats/data/NonEmptyVector<TA;>;Lcats/data/NonEmptyVector<TB;>;Lcats/data/OneAnd<Lscala/collection/immutable/Vector;TA;>;Lcats/data/OneAnd<Lscala/collection/immutable/Vector;TB;>;>; rather than <A:Ljava/lang/Object;B:Ljava/lang/Object;>()Lmonocle/PIso<Lscala/collection/immutable/Vector<TA;>;Lscala/collection/immutable/Vector<TB;>;Lcats/data/OneAnd<Lscala/collection/immutable/Vector;TA;>;Lcats/data/OneAnd<Lscala/collection/immutable/Vector;TB;>;>;
// Lots more here...

[dwijnand]

Formatted the error:

[error]  * method pNevToOneAnd()monocle.PIso in object monocle.Monocle has a different signature in current version, where it is

<A: Ljava/lang/Object; B: Ljava/lang/Object;> () Lmonocle/PIso<
  Lcats/data/NonEmptyVector<TA;>;
  Lcats/data/NonEmptyVector<TB;>;
  Lcats/data/OneAnd<Lscala/collection/immutable/Vector; TA;>;
  Lcats/data/OneAnd<Lscala/collection/immutable/Vector; TB;>;
>; rather than

<A: Ljava/lang/Object; B: Ljava/lang/Object;> () Lmonocle/PIso<
  Lscala/collection/immutable/Vector<TA;>;
  Lscala/collection/immutable/Vector<TB;>;
  Lcats/data/OneAnd<Lscala/collection/immutable/Vector; TA;>;
  Lcats/data/OneAnd<Lscala/collection/immutable/Vector; TB;>;
>;

The value was always boxed, that just wasn't reflected in the java signature until scala/scala#8127.

There is an enhancement in MiMa which aspires to spot this so users aren't thrown by it: lightbend-labs/mima#423

Note we recently added this piece of doc to the readme about IncompatibleSignatureProblem: https://github.com/lightbend/mima#incompatiblesignatureproblem. That's part of the error message in a future release: https://github.com/lightbend/mima/pull/435/files.

[travisbrown]

Ha, I totally forgot that I had reported this.