ktfmt migration roadmap

[AbdullinAM]

• Phase 1: Initial transfer and integration

  • Transfer ktfmt repository to the Kotlin org on GitHub
  • Migrate the sources from com.facebook.* package to org.jetbrains.kotlin.*
  • Clean up OS-dependent scripts and tests, replace them with OS-independent analogs
  • Set up CI in Kotlin Tools and Libraries TeamCity server
  • Set up the publishing process
  • Update ktfmt repo documentation/licence/etc.
  • Sync on the status of the Gradle plugin and IntelliJ plugin

• Phase 2: Kotlin repo adoption

  • Kotlin repo formatting audit
    • sync on the current discrepancies in formatting in Kotlin repo
    • update ktfmt defaults where necessary
    • decide on the future of the --kotlinlang-style option
    • analyze the performance/memory impact/developer experience
  • Decide on the ktfmt in Kotlin workflow
    • how is the reformatting performed: IDE (IntelliJ plugin), Gradle, cli
    • when is the reformatting performed: incremental, on save, on commit, on push, on CI
  • Perform one-time reformat of the Kotlin repo
    • decide how to handle branch/PR conflicts
  • Set up CI checks and auto-reformatting
  • Update contribution guidelines
  • Configure ktfmt for the other official Kotlin repos
  • Set up ktfmt vs. Kotlin co-development processes
    • ktfmt vs. Kotlin versioning, decide on alpha/beta/experimental/release status of ktfmt
    • decide how and when new features are added

• Phase 3: Long-term community adoption and endorsement

  • Stabilise the API surface so that external tools can rely on ktfmt
  • Update documentation in https://kotlinlang.org/ to recommend ktfmt
    • provide official IDE/CI setup recommendations
    • provide official Gradle/Maven/other build tools integration
  • Adopt ktfmt as a default formatter in IntelliJ
    • analyze the performance/memory impact
    • define deprecation/migration pipeline
    • sunset ktfmt IntelliJ plugin

[staktrace]

how is the reformatting performed: IDE (IntelliJ plugin), Gradle, cli
when is the reformatting performed: incremental, on save, on commit, on push, on CI

Just wanted to note that we solved these problems in our kotlin-formatter wrapper and it works well - provides a consistent formatting experience using ktfmt across IntelliJ, Gradle, CLI, and git hooks: https://github.com/block/kotlin-formatter/#why-kotlin-formatter. Feel free to use it!

[AbdullinAM]

@staktrace I will take a look, thanks!

[okarmazin]

Will JetBrains keep ktfmt extremely opinionated and purposefully unconfigurable? Will it at least allow // @formatter:off for the cases where ktfmt misses the mark?

[AbdullinAM]

@okarmazin we are currently still investigating, but partially yes