Use new Kotlin frontend

[fwcd]

Update (June 2022):

A prototype of a language server using the new analysis APIs can be found in the kotlin-analysis-server repo. Note that this is not production ready and mostly intended as a playground for experimentation currently.

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The Kotlin frontend is currently undergoing large architectural changes with the migration to FIR and will provide some new APIs for IDE-related usage that we could hook into, once ready.

The interesting modules seem to be mostly located in analysis (in the Kotlin repo). Useful resources:

• Official Kotlin repo:
  • The docs for the analysis API
    • ...including this overview of the API (explicitly mentions LSP as a use case)
    • ...and this usage doc
  • KtAnalysisSession from analysis
  • The analysis-api-standalone project
• IntelliJ IDEA repo:
  • The new Kotlin plugin, along with its implementation of completions
• Kotlin Symbol Processor (KSP):
  • An example project using the standalone analysis API
  • See this build.gradle.kts for an example of the Maven repos and dependencies needed for the analysis API
  • See this main method for an example how to bootstrap the compiler/analysis APIs
• Kotlin Website:
  • This roadmap
• YouTrack:
  • This issue tracking standalone mode for the analysis API (explicitly mentions LSP as a use case)
  • This issue regarding prototyping of an IDE plugin
  • This issue regarding use of Analysis API with Frontend 1.0
• Kotlin Blog:
  • This blog post: The road to the K2 compiler
    • The linked YouTube video, which includes an overview over the new compiler architecture
• Kotlin Slack (requires invitation, see here):
  • Discussion of some FIR internals
  • This diagram of the Kotlin compiler architecture