scala/scala-parallel-collections

This system is a community-maintained library providing parallel collection implementations for Scala 2.13 and Scala 3, extracted from the standard library. It offers core infrastructure for parallel data structures, including immutable hash-tries and concurrent maps, along with utilities for converting between standard and parallel collections. The project focuses on ensuring behavioral consistency with sequential operations and serialization stability across different Scala versions.

The testmacros module now includes a new \ShouldNotTypecheck\ utility in the \testutil\ package, available for both Scala 2 and Scala 3. This tool allows tests to verify that specific code snippets fail to typecheck, ensuring that expected compilation errors are correctly triggered. The Scala 2 implementation uses macros to parse and typecheck code, while the Scala 3 version leverages \scala.compiletime.testing.typeChecks\ for inline verification.

testmacros · high confidence

The parallel collections previously included in the Scala standard library (Scala 2.10–2.12) are now available as a separate, community-maintained module under the Apache 2.0 license. Users of Scala 2.13 and Scala 3 can opt-in by adding the \scala-parallel-collections\ dependency and importing \scala.collection.parallel.CollectionConverters.\_\, while earlier Scala versions remain unaffected.

(repo-wide) · high confidence

This release introduces the initial implementation of parallel collections, adding core infrastructure such as the \Parallel\ and \Parallelizable\ traits, generic factory templates (\GenericParCompanion\, \ParFactory\), and internal support for task combining and signaling. It also includes the foundational immutable hash-trie data structures (\OldHashMap\, \OldHashSet\) and their iterators, which serve as the basis for the new parallel collection types.

core · high confidence

Added serialization stability tests for Scala 3; Added test coverage for collection conversions, parallel collect, and concurrent TrieMap; Added tests for parallel collections and serialization stability; Initial property-based tests for parallel collections.

The build system has been upgraded to sbt 1.13.0, with the sbt-scala-module plugin updated to 3.4.1 and sbt-projectmatrix to 0.11.0. Additionally, Scala Native support is now provided via version 0.5.12 of the sbt-scala-native plugin. A new build tool, GetScala3Next, was added to automatically fetch the latest Scala 3 next-version tag from the GitHub API, enabling dynamic cross-building against upcoming Scala 3 releases.

project · high confidence

The build configuration now targets Scala versions 2.13.18 and 3.3.8, replacing previous versions. Test dependencies have been updated to JUnit 4.13.2, junit-interface 0.13.3, JAXB API 2.3.1, and ScalaCheck 1.20.0. The build also configures Scala 2.13 compilation with the -Xsource:3 option for forward compatibility and enables -Werror for stricter warning handling.

(dependencies) · high confidence

Written by watchdog.canine.dev from the codebase's own history, inside the signed delivery this page is composed from.

• First survey — no prior run to compare against. CAI 63.

• Code Health 94
• Architecture 99
• Maturity 53
• Readiness 61
• Security 70

• 300 commits — 289 feature/other, 11 fixes

• (root) — 88 commits
• project/build.properties — 69 commits
• (repo) — 62 commits
• project/plugins.sbt — 27 commits
• core/src — 25 commits
• .github/workflows — 19 commits
• junit/src — 6 commits
• scalacheck/src — 2 commits
• .github/dependabot.yml — 1 commit
• project/GetScala3Next.scala — 1 commit

• fix: Fix compilation
• fix: Fix compilation of GetScala3Next
• fix: Merge pull request #132 from SethTisue/fix-scala3-doc-jar
• fix: Merge pull request #203 from SethTisue/fix-ci
• fix: Merge pull request #278 from scala/fix-ci-and-add-cla
• fix: Merge pull request #308 from scala/fix-distributivity
• fix: fix CI some more
• fix: fix Scala 3 publishing
• fix: fix sbt 1.7 upgrade (#225)
• fix: fix versionPolicyCheck
• fix: fix: update parent type of ParSeqLike
• change: Add -Xsource:3 option
• change: Add command for JVM/Native tests, use them in the CI
• change: Add java 21 to build matrix (#261)
• change: Adjust build definition and CI process
• change: AdoptOpenJDK is now Temurin (#196)
• change: Bump actions/checkout from 4 to 6
• change: Bump actions/checkout from 6 to 7
• change: Bump actions/setup-java from 4 to 5
• change: Bump actions/setup-java from 5 to 6
• …and 280 more

Written by watchdog.canine.dev from the codebase's own history, inside the signed delivery this page is composed from.

scala/scala-parallel-collections was measured the same way every project in this corpus was: the same rubric, at a pinned commit, with the result published in full. Point a surveyor at a repository you know and see whether you agree with it.