Fix StackOverflowError in Kotlin parser for deeply nested binary expressions#7083
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Fix StackOverflowError in Kotlin parser for deeply nested binary expressions#7083
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…essions Convert recursive left-child traversal in visitBinaryExpression to an iterative approach, collecting the left spine of nested KtBinaryExpression nodes and processing them bottom-up. This prevents stack overflow when parsing deeply nested expressions (e.g. 2000+ string concatenations).
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Should be re-enabled? |
sambsnyd
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Mar 31, 2026
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sambsnyd
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Looks reasonable to me. Why is this still a draft?
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Summary
KotlinTreeParserVisitor.visitBinaryExpression()to an iterative approachKtBinaryExpressionnodes into a list and processes them bottom-up, preventingStackOverflowErroron deeply nested expressions (e.g. 2000+ string concatenations)mapFunctionCall()to accept a pre-computed left expression instead of re-visiting the left childFixes the CI failure: https://github.com/openrewrite/rewrite/actions/runs/23356509331/job/67948579231
Test plan
BinaryTest.deeplyNestedStringConcatenation()now passes (was failing withStackOverflowError)rewrite-kotlintest suite passes (1173 tests, 0 failures)