investigate 2.13 community build breakage for 2.13.0-RC1

[SethTisue]

current nightly: 2.13.0-pre-59975bb 2.13.0-pre-af24410 2.13.0-pre-b4926ef

I did a sweep through the latest run log at https://scala-ci.typesafe.com/job/scala-2.13.x-integrate-community-build/ , findings as follows (numbers are "number of downstream projects blocked")

advice for those who want to help is now up at https://github.com/scala/community-builds/wiki/Troubleshooting-a-failure . I can expand and update it in response to questions. you can also help simply by eyeballing a failure and investigating it by reading code, and posting your findings here

might possibly have hit as-yet-unknown 2.13 regressions:

• 3 "http4s-parboiled2", // diverging implicit expansion -- could be a Scala regression, looks tricky to troubleshoot
• 1 "circe-jackson", // appears to have run afoul of recent (Feb? Mar?) changes to overloading resolution? could possibly be a Scala regression
• 1 "parboiled2", // same as http4s-parboiled2

I also found some projects that are only failing for trivial-looking reasons. we could submit upstream fixes, or just put fixes or workarounds in our forks, and see if that uncovers any real issues (or, in some cases, unblocks downstream stuff):

• 10 "monix" // compile errors because of new PartialFunction overload, should be easy workaround
• 3 "silencer", // test failure, maybe just a changed error message wording?
• 3 "scala-logging", // runs afoul of new rules about varargs overloading
• 2 "grizzled", // M5 compat is in place, but there are collections-related compile errors, maybe just needs post-M5 tweaks?
• 0 "scalajson", // looks like it might be hitting Som's change where import shadows local identifiers?
• 0 "scallop", // trivial post-M5 remove vs removed fix needed

and then this is a dilemma:

• 13 "scalapb", // dilemma: on master they have M5 support, but they also require Fastparse 2. what to do?

fixed

• 9 "scopt", // no arguments allowed for nullary method thank you @xuwei-k
• 2 "specs2-more", // overly sensitive test thank you @etorreborre
• 1 "base64", // needs workaround for Can't call scala.StringBuilder#length_= in 2.13.0-M5 #11158 which won't be fixed in RC1 thank you @xuwei-k and @marklister
• 1 "scalariform", // looks like a trivial compile error perhaps related to removal of foo bar () syntax thank you @Philippus and @godenji
• 0 scala-parallel-collections thank you @eed3si9n
• 0 scala-collection-laws scala/community-build@53ff214
• 0 "twotails", // "no arguments allowed for nullary method" thank you @Philippus
• 0 "scodec", // we just needed to use the branch where 2.13 support is present
• 0 "airframe", // serialization related test failures, thank you @xerial

not green, but investigated, and no unreported Scala regression seems present

• 0 scala-js scala/community-build@e5c65e2 thank you @adriaanm
• 0 "kittens", // hashing-related test failure thank you @joroKr21
• 0 "scala-swing", // looks like it needs tweaks for post-M5 changes thank you @Sciss

[joroKr21]

I would like to check the kittens issue if no one beats me to it. How can I reproduce it?

[SethTisue]

How can I reproduce [a failure]?

advice for those who want to help is now up at https://github.com/scala/community-builds/wiki/Troubleshooting-a-failure . I can expand and update it in response to questions

you can also help simply by eyeballing a failure and investigating it by reading code, and posting your findings here

[SethTisue]

@etorreborre what do you make of the specs2-more failure?

[specs2-more] [error]   x h2 id="1"/> ++ <h3/>).updateHeadAttribute("id", 3) === (<h2 id='3'/> ++ <h3/>)
[specs2-more] [error]  <h2 id="3"/><h3/> != List(<h2 id="3"/>, <h3/>) (HtmlxSpec.scala:15)
[specs2-more] [info]   + h2>hello</h2>.addHeadersAnchors.toString must beMatching("<a name=\"hello\"><h2>hello</h2></a>")
[specs2-more] [info]   the headers methods
[specs2-more] [error]     x collects all headers of a document
[specs2-more] [error]  <h1>title1</h1><h2>title2</h2> != List(<h1>title1</h1>, <h2>title2</h2>) (HtmlxSpec.scala:50)

[adriaanm]

I fixed the scala-js issue in https://github.com/scalacommunitybuild/scala-js/tree/community-build-2.13 but forgot to update the ref I guess -- I'll submit as a PR and see

[SethTisue]

@adriaanm I already pushed scala/community-build@e5c65e2, let's assume it will go green, I'll come back to it if not

[Jasper-M]

"base64", // StringBuilder stopped allowing assignment to its .length member? is that an intentional change we made?

This is #11158

[SethTisue]

This is #11158

@adriaanm says a proper fix isn't possible right now, so we'd have to just work around it in base64. (but note that base64 is only blocking one downstream project.)

[etorreborre]

@SethTisue I tried a small change to the expectations in HtmlxSpec: b3649e9e7. Let's see how it goes

[SethTisue]

@etorreborre that does it, thanks!

[info] Project specs2----------------------: SUCCESS (project rebuilt ok)
[info] Project specs2-more-----------------: SUCCESS (project rebuilt ok)

[joroKr21]

The failing tests in kittens test that the derived Hash is the same as Scala's Hashing and hashCode. I guess the cause is scala/scala#7693.

But I'm not sure:

• Why do we need Hash derivation if the only allowed implementation is the same as hashCode?
• How to fix it? I guess have a special instance when A <: Product but what about cross compilation?

[Sciss]

I don't really understand the scala-swing errors in https://scala-ci.typesafe.com/job/scala-2.13.x-integrate-community-build/1895/consoleFull
They all seem to stem from the fact that sbt doesn't see MapWrapper, SetWrapper, BufferWrapper. But they are in the sources: https://github.com/scala/scala-swing/blob/work/src/main/scala-2.13.0-M5/scala/swing/MapWrapper.scala

Could the problem be that sbt is not assuming source directory src/main/scala-2.13.0-M5 simply because the version is no longer -M5?

[smarter]

Could the problem be that sbt is not assuming source directory src/main/scala-2.13.0-M5 simply because the version is no longer -M5?

Yup. To get something more fine-grained you can set up your own rules in your build, e.g.: https://github.com/akka/akka/blob/65ccada280cf4a08701b0b05f7efab46560447ff/project/AkkaBuild.scala#L128-L137