Release 2.12.8

[lrytz]

SCALA_SHA=38cd84d976880eab16af17a44d186bbddcd554f2
DIST_SHA=d8cf4f730a6d50411ea59a5e0df4e1f651255d48

Key links:

• scala/scala milestone: https://github.com/scala/scala/milestone/76
• scala/bug milestone: https://github.com/scala/bug/milestone/97
• scala/scala-dev milestone: https://github.com/scala/scala-dev/milestone/26

N weeks before the release

• Wind down PR queue. There has to be enough time after the last (non-trivial) PR is merged and the next phase. The core of the eco-system needs time to prepare for the final!
• Triage scala/bug and scala/scala-dev tickets
• Create next scala/scala milestone
• Close the scala/bug milestone, create next milestone, move pending issues
• Close the scala/scala-dev milestone, create next milestone, move pending issues
• Check PRs assigned to the milestone, also check WIP
• Announce expected release date and current nightly "release candidate" (nightly sha-mangled version) at https://scala-ci.typesafe.com/artifactory/scala-integration/ on https://contributors.scala-lang.org/c/announcements

Release announcement / notes

• Notify community on https://contributors.scala-lang.org/c/announcements
• Review merged PRs, make sure release-notes label is applied appropriately
• PRs with release-notes label must have excellent title & description (title will be pasted literally in release note bullet list)
• Draft release notes (to be published once GitHub tag is pushed)
  • note that GitHub release notes drafts can only be viewed by committers, so use a gist to draft the notes, so the gist can be shared with the community
• On contributors thread, link to release note gist and request feedback
• Prepare PR to https://github.com/scala/scala-lang/ (using scala/make-release-notes which requires a staged release and a pushed tag)
  • documentation/api.md
  • download/index.md
  • _config.yml (update devscalaversion or scalaversion)

N days before release

• Announce no more PRs will be merged unless last-minute regressions are found. Re-iterate current nightly sha version for testing.
• Community build: Release 2.12.8 #582 (comment)
• Windows Jenkins job
• Check any merged PRs accidentally assigned to the next milestone in this branch, and re-assign them to this milestone
• Merge in any older release branch
• Check module versioning (is everything in versions.properties up to date?)

Point of no return

• Once sufficient time has passed since last merged PR (1-2 weeks depending on whether it's a maintenance or development branch), and core projects have tried out the candidate nightly, it's time to cut the release!
• Make sure there are no stray staging repos on sonatype
• Trigger a build on travis, specify SCALA_VER_BASE and SCALA_VER_SUFFIX in the custom config
  • config: before_install: export SCALA_VER_BASE=2.12.8 SCALA_VER_SUFFIX=
    • https://travis-ci.org/scala/scala/jobs/463241730
  • Check the build status on https://github.com/scala/scala/commits/2.12.x
  • Check that the scala/scala job also triggered a following scala/scala-dist job: https://travis-ci.org/scala/scala-dist/builds/463260501
  • Note the scala/scala commit (the full 40-char sha!)
  • Create the scala/scala tag locally: git tag -s -m "Scala 2.12.8" v2.12.8 38cd84d976880eab16af17a44d186bbddcd554f2
  • Note the scala/scala-dist commit (the full 40-char sha!)
  • Create scala-dist tag locally: git tag -s -m "Scala 2.12.8" v2.12.8 d8cf4f730a6d50411ea59a5e0df4e1f651255d48
  • Note the repos to be promoted after tag is cut (see travis log)
    • https://oss.sonatype.org/content/repositories/orgscala-lang-1655/
    • https://oss.sonatype.org/content/repositories/orgscala-lang-1656/
• Sanity check jar/pom
  • https://oss.sonatype.org/content/repositories/staging/org/scala-lang/scala-compiler/2.12.8/
  • in particular, if the release was staged multiple times, double check that https://oss.sonatype.org/content/repositories/staging/ has the files from the most recent build
• Remember, tags are forever, so are maven artifacts (even staged ones, as they could end up in local caches) and S3 uploads (S3 buckets can be changed, but it can takes days to become consistent)
• Push scala/scala tag: git push https://github.com/scala/scala.git v2.12.8
• Add release notes to https://github.com/scala/scala/releases/tag/v2.12.8
• Push scala/scala-dist tag: git push https://github.com/scala/scala-dist.git v2.12.8
• Trigger two scala-dist jobs on travis (https://travis-ci.org/scala/scala-dist) with custom config. must use full-length SHAs!
  • before_install: export version=2.12.8 scala_sha=38cd84d976880eab16af17a44d186bbddcd554f2 mode=archives: https://travis-ci.org/scala/scala-dist/builds/463287808
  • before_install: export version=2.12.8 scala_sha=38cd84d976880eab16af17a44d186bbddcd554f2 mode=update-api: https://travis-ci.org/scala/scala-dist/builds/463324882
• Promote staging repos: st_stagingRepoPromote [scala-repo], st_stagingRepoPromote [modules-repo] (or use oss.sonatype.org web UI)

Check availability

• Check release on sonatype: https://oss.sonatype.org/content/repositories/releases/org/scala-lang/scala-compiler/2.12.8/
• Check the release on maven central: http://central.maven.org/maven2/org/scala-lang/scala-compiler/2.12.8/
• Check the release on maven search (takes longer): http://search.maven.org/#search%7Cga%7C1%7Cg%3Aorg.scala-lang%20v%3A2.12.8

When everything is on maven central

• make sure the draft release notes are on GitHub tag: https://github.com/scala/scala/releases/tag/v2.12.8
• Pre-announce the release on https://contributors.scala-lang.org/c/announcements
• Check that the API docs are published
  • http://www.scala-lang.org/api/2.12.8/
  • https://docs.scala-lang.org/api/all.html
• Merge the scala-lang PR
  • wait for it to reach https://www.scala-lang.org and make sure it looks okay

Modules

• if it's a 2.12.x release, publish macro paradise for the new version

Announcements

• Scala Users discourse https://users.scala-lang.org
• add a reply on the same https://contributors.scala-lang.org thread where you announced that the release process was starting
• Tweet from @scala_lang
• https://gitter.im/scala/scala
  • if you feel like it, say something in https://gitter.im/scala/contributors too
• ask Seth to announce on #scala IRC

Afterwards

• Create PR to update versions.properties (new file generated by the bootstrap job) and the baseVersion in build.sbt

[SethTisue]

I bumped the community build Scala SHA just now (scala/community-build@ac02adb) and triggered a fresh run at https://scala-ci.typesafe.com/view/scala-2.12.x/job/scala-2.12.x-integrate-community-build/

[SethTisue]

I (provisionally) closed the 2.12.8 milestone and made new 2.12.x PRs target 2.12.9.

[SethTisue]

Community build is green on 2.12.8-bin-25c7215

[SethTisue]

@lrytz we might want to wait for a reply from @japgolly at scala/bug#11174

[SethTisue]

community build run on 2.12.8-bin-38cd84d: https://scala-ci.typesafe.com/view/scala-2.12.x/job/scala-2.12.x-integrate-community-build/3821/

UPDATE: it went green in run 3823

[lrytz]

I'm planning to run the release scripts on 38cd84d tomorrow.

[SethTisue]

did you make a decision about backporting scala/scala#7438 ?

[lrytz]

I think 2.12.9 is fine, it's an old bug after all (since 2.12.0)

[lrytz]

Beh, travis failed with java.io.IOException: PUT operation to URL https://oss.sonatype.org/service/local/staging/deploy/maven2/org/scala-lang/scala-library-all/2.12.8/scala-library-all-2.12.8.pom failed with status code 504: Gateway Time-out.

I think at this stage I can just re-try, nothing has been published / uploaded except for the artifacts in the staging repo, which I can drop.

EDIT: rebuild worked.

[SethTisue]

@lrytz shouldn't the release notes mention the license change to Apache 2?

[SethTisue]

@lrytz also scala/scala-lang#958 can be merged at the time you redo scala/scala-lang#980

[SethTisue]

come to think of it, the license change is also important enough to mention in the blog post