Scala 2.13.0(-M5) support

[Sciss]

We need some help getting this done. As Scala Swing heavily relies on the collections API, I assume this is not a trivial task. Opening this issue as a point of contact.

[som-snytt]

I'm spending a few minutes with this. It looks like one problem is that imports are used incorrectly, but the compiler bug was fixed.

[Sciss]

Ok great. I was mainly thinking about things like these:

https://github.com/scala/scala-swing/blob/2.0.x/src/main/scala/scala/swing/BufferWrapper.scala

But perhaps I'm wrong and this already compiles correctly most of the time.

[som-snytt]

Seq changed, and also some imports collided because of naming.

Quickie branch that compiles under 2.13 latest but not previous:
https://github.com/som-snytt/scala-swing/tree/issue/84

A few signatures are ???.

It looks like you have to implement += under the old regime but it's final under the new. That might require a branch.

Compare: https://github.com/scala/scala-swing/compare/2.0.x...som-snytt:issue/84?expand=1

[Sciss]

@som-snytt I don't see any ??? in your branch?

[som-snytt]

@Sciss I updated. I found my old scala-swing app from 2011, but I couldn't build it against 2.9 anymore. I was about to try it out against the revision on 2.13... I may need another coffee.

So it has a shim to do the switch from += to addOne on 2.12. I failed to use one shim for Growable/Shrinkable, so just made one each for Buffer, Set, Map. About to get around to trying it out.

[SethTisue]

• https://repo1.maven.org/maven2/org/scala-lang/modules/scala-swing_2.13.0-M5/2.1.0/
• scala/make-release-notes@549b921