GROOVY-11905: Optimize non-capturing lambdas

[daniellansun]

https://issues.apache.org/jira/browse/GROOVY-11905

[codecov-commenter]

Codecov Report

❌ Patch coverage is 91.14391% with 24 lines in your changes missing coverage. Please review.
✅ Project coverage is 66.5402%. Comparing base (d009dd2) to head (078cdef).

Files with missing lines	Patch %	Lines
...ovy/classgen/asm/sc/StaticTypesLambdaAnalyzer.java	91.2281%	1 Missing and 14 partials ⚠️
...roovy/classgen/asm/sc/StaticTypesLambdaWriter.java	91.0000%	4 Missing and 5 partials ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##               master      #2438        +/-   ##
==================================================
+ Coverage     66.4917%   66.5402%   +0.0485%     
- Complexity      30294      30334        +40     
==================================================
  Files            1412       1413         +1     
  Lines          118108     118315       +207     
  Branches        20999      21054        +55     
==================================================
+ Hits            78532      78727       +195     
  Misses          33095      33095                
- Partials         6481       6493        +12     

Files with missing lines	Coverage Δ
...roovy/classgen/asm/sc/StaticTypesLambdaWriter.java	94.4751% <91.0000%> (-2.7662%)	⬇️
...ovy/classgen/asm/sc/StaticTypesLambdaAnalyzer.java	91.2281% <91.2281%> (ø)

... and 5 files with indirect coverage changes

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[Copilot]

Pull request overview

This PR implements GROOVY-11905 by optimizing statically-compiled, non-capturing lambdas to avoid per-invocation allocations by emitting a static doCall target and using capture-free invokedynamic/LambdaMetafactory bootstraps, with extensive new bytecode and behavioral tests.

Changes:

• Add a lambda analysis pass to detect instance-member capture and qualify outer static member references to remain capture-free.
• Update static-compilation lambda bytecode generation to use H_INVOKESTATIC/no captured receiver when safe, and adjust serializable-lambda deserialization helpers accordingly.
• Expand test coverage for non-capturing vs capturing lambdas (behavioral + bytecode assertions) and update an existing type-annotation expectation.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/test/groovy/org/codehaus/groovy/classgen/asm/TypeAnnotationsTest.groovy	Updates expected lambda doCall signature to match new static non-capturing implementation.
src/test/groovy/groovy/transform/stc/LambdaTest.groovy	Adds a large nested test suite covering non-capturing/capturing semantics and emitted bytecode patterns.
src/main/java/org/codehaus/groovy/classgen/asm/sc/StaticTypesLambdaWriter.java	Implements capture-free invokedynamic generation for non-capturing lambdas and refactors serialize/deserialize support.
src/main/java/org/codehaus/groovy/classgen/asm/sc/StaticTypesLambdaAnalyzer.java	New analyzer to detect capture and qualify outer static member references for static doCall.
src/main/java/org/codehaus/groovy/ast/ClassNode.java	Caches getOuterClasses() result.

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[Copilot]

getOuterClasses() now caches the computed list in a field, but the implementation doesn’t account for redirect/proxy ClassNodes. Since setRedirect(...) can be called later for non-primary nodes, a proxy may cache Collections.emptyList() (or an outdated chain) before redirect is set/changed and then return stale results thereafter. Consider delegating to redirect().getOuterClasses() when redirect != null and/or clearing outerClasses in setRedirect(...) to keep the cache correct.