Proposal: Add `rewrite` support for `errorprone.refasterrules`

[Pankraz76]

Proposal: Add rewrite support for errorprone.refasterrules

I’d like to propose integrating Google’s Error Prone and its Picnic extension (demonstrated in Automating Away Bugs with Error Prone | PlatformCon 2023) to enable automated bug fixes via rewrite rules. This would complement Checkstyle’s static analysis capabilities by addressing semantic bugs rather than stylistic issues.

Motivation

Error Prone’s refaster/rewrite rules can automatically:

• Fix common bug patterns (e.g., String.equals() misuse)
• Modernize code (e.g., JDK migration helpers)
• Enforce best practices (e.g., null-check improvements)

Real-world adoptions show tangible benefits:

• Fix #5953: [java] PoC: Add rewrite support for errorprone.refasterrules pmd/pmd#5956
• Issue #17487: Add rewrite support for errorprone.refasterrules checkstyle/checkstyle#17490
• PoC: Add rewrite support for errorprone.refasterrules kafka#20219
• PoC: Add rewrite support for errorprone.refasterrules diffplug/spotless#2576

Proposal

1. Add support for errorprone.refasterrules-based rewrites
2. Implement with opt-in adoption (no breaking changes)
3. Include suppression mechanisms for API constraints

Discussion Points

• Need consensus on:
  • Scope of auto-fixes
  • Preferred suppression strategy
  • Integration approach

Next Steps

I’m happy to:

• Prepare a PoC demonstrating the value
• Collaborate on implementation strategy
• Address any concerns about compatibility