Release 2.13.0

[SethTisue]

Variables to be expanded in this template (or export them in a local terminal, so that you can copy/paste the commands below without replacing anything):

• SCALA_VER_BASE="2.13.0"
• SCALA_VER_SUFFIX=""
• SCALA_SHA=43e040ff7e4ba92ccf223e77540580b32c1473c0
• DIST_SHA=4507b42f85a51cec140d1fb230a2ea34d02eb697
• SCALA_VER="$SCALA_VER_BASE$SCALA_VER_SUFFIX"

Key links:

• scala/scala milestone: https://github.com/scala/scala/milestone/81
• scala/bug milestone: https://github.com/scala/bug/milestone/99
• scala/scala-dev milestone: https://github.com/scala/scala-dev/milestone/28

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, move the magical "Merge to 2.13.x" description to it (so Scabot uses it as default for new PRs)
• 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)
• Prepare PR to https://github.com/scala/docs.scala-lang/
  • api/all.md

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
  • won't be anywhere near all green, but we should make sure some nontrivial number of projects are still green
  • run with expected-greens only: https://scala-ci.typesafe.com/job/scala-2.13.x-integrate-community-build/?
  • also do a full run to see if there are any unexpected greens
• Run scala-collections-laws and evaluate results
  • Rex Kerr (@Ichoran) is the keeper and expert on this
• Windows Jenkins job
  • don't just trust the automated nightly runs, manually trigger a run on the exact SHA
  • https://scala-ci.typesafe.com/job/scala-2.13.x-integrate-windows/?
• 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?)
• On major release, bump PickleFormat version
  • added to: branch for 2.14 #634

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: https://travis-ci.org/scala/scala/builds/542650556 (failed at first because compiler-bridge_2.13 was missing at zinc version 1.2.5 -- backpublished)
  • config: before_install: export SCALA_VER_BASE=$SCALA_VER_BASE SCALA_VER_SUFFIX=$SCALA_VER_SUFFIX
  • Check the build status on https://github.com/scala/scala/commits/2.13.x
  • Check that the scala/scala job also triggered a following scala/scala-dist job: https://travis-ci.org/scala/scala-dist/builds/?
  • Note the scala/scala commit (the full 40-char sha!)
  • Create the scala/scala tag locally: git tag -s -m "Scala $SCALA_VER" v$SCALA_VER $SCALA_SHA
  • Note the scala/scala-dist commit (the full 40-char sha!)
  • Create scala-dist tag locally: git tag -s -m "Scala $SCALA_VER" v$SCALA_VER $DIST_SHA
  • Note the repos to be promoted after tag is cut (see travis log)
    • https://oss.sonatype.org/content/repositories/orgscala-lang-1790
• Sanity check jar/pom
  • https://oss.sonatype.org/content/repositories/staging/org/scala-lang/scala-compiler/$SCALA_VER/
  • 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 v$SCALA_VER
• Add release notes to https://github.com/scala/scala/releases/tag/v$SCALA_VER
• Push scala/scala-dist tag: git push https://github.com/scala/scala-dist.git v$SCALA_VER
• Trigger two scala-dist jobs on travis (https://travis-ci.org/scala/scala-dist) with custom config. must use full-length SHAs!
  • before_install: export version=$SCALA_VER scala_sha=$SCALA_SHA mode=archives: https://travis-ci.org/scala/scala-dist/builds/542716770
  • before_install: export version=$SCALA_VER scala_sha=$SCALA_SHA mode=update-api: https://travis-ci.org/scala/scala-dist/builds/542721620
• Promote staging repos: st_stagingRepoPromote orgscala-lang-1790

Check availability

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

When everything is on maven central

• make sure the draft release notes are on GitHub tag: https://github.com/scala/scala/releases/tag/v$SCALA_VER
• Pre-announce the release on https://contributors.scala-lang.org/c/announcements
• On 2.13.0 only: (manually) update the current symlink for the API docs
  • https://github.com/scala/scala-dist/blob/2.13.x/scripts/jobs/release/website/update-api#L15
• Check that the API docs are published
  • http://www.scala-lang.org/api/$SCALA_VER/
  • https://docs.scala-lang.org/api/all.html ?
• Merge the scala-lang PR and the docs.scala-lang.org PR
  • wait for them to arrive on the websites and make sure they look okay

Modules

• build and release scala-collection-compat and other modules (or open tickets asking that the maintainers do so)
  • this work has moved to https://github.com/scala/make-release-notes/blob/2.13.x/projects-2.13.md
• 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 scala-version on docs.scala-lang.org (example: bump scala-version docs.scala-lang#1294)
• Create PR to update versions.properties (new file generated by the bootstrap job) and the baseVersion in build.sbt and the MiMa base version and exclusion filters
• Create PR to update https://github.com/lightbend/reactive-platform-docs/blob/master/src/main/paradox/supported-modules/index.md
• Update WhiteSource
  • it's on Seth's personal todo list

[adriaanm]

🎉

[SethTisue]

website PRs:

• Scala 2.13 release scala-lang#1046
• Scala 2.13 release docs.scala-lang#1357

[SethTisue]

https://twitter.com/scala_lang/status/1138322341757378560