GROOVY-12098: Pre/post increment on array element double-evaluates th…

[paulk-asert]

…e receiver

[Copilot]

Pull request overview

Note

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Adds regression coverage and fixes bytecode generation so pre/post inc/dec on subscript expressions (a[i]++, ++a[i], etc.) evaluates the receiver and index exactly once and in left-to-right order.

Changes:

• Introduces a new regression test suite for GROOVY-12098 covering order, single-evaluation, and value semantics for arrays/lists (including @CompileStatic cases).
• Updates BinaryExpressionHelper to cache both subscript receiver and index into temporaries and reuse them for the read (getAt) and write (putAt) paths.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
src/test/groovy/bugs/Groovy12098.groovy	Adds regression tests verifying evaluation order, single-evaluation, and correct values for array/list subscript inc/dec.
src/main/java/org/codehaus/groovy/classgen/asm/BinaryExpressionHelper.java	Caches subscript receiver+index into temporaries to prevent double-evaluation during read-modify-write operations.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 96.55172% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 68.4796%. Comparing base (40c6203) to head (19149bb).
⚠️ Report is 5 commits behind head on master.

Files with missing lines	Patch %	Lines
...us/groovy/classgen/asm/BinaryExpressionHelper.java	96.5517%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@                Coverage Diff                 @@
##               master      #2621        +/-   ##
==================================================
+ Coverage     68.4541%   68.4796%   +0.0255%     
- Complexity      33505      33524        +19     
==================================================
  Files            1518       1518                
  Lines          127107     127124        +17     
  Branches        23065      23064         -1     
==================================================
+ Hits            87010      87054        +44     
+ Misses          32371      32333        -38     
- Partials         7726       7737        +11     

Files with missing lines	Coverage Δ
...us/groovy/classgen/asm/BinaryExpressionHelper.java	88.9580% <96.5517%> (+0.1401%)	⬆️

... and 8 files with indirect coverage changes

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[testlens-app]

✅ All tests passed ✅

🏷️ Commit: 19149bb
▶️ Tests: 87857 executed
⚪️ Checks: 30/30 completed

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