paulk-asert opened a new pull request, #2796: URL: https://github.com/apache/groovy/pull/2796
…member being visited Temporary type information from instanceof is keyed by the target variable — for a field access, the shared FieldNode. if/loops/ternaries and expression statements bracket their own frames, but a narrowing recorded at statement level (an explicit `return field instanceof Sub`, or an `assert field instanceof Sub`, whose propagation to subsequent statements is intentional) lands in the enclosing frame, which was the frame pushed for the whole class visit. Keyed by the shared FieldNode, it then applied to every member visited afterwards: the checker stamped the narrowed type on unrelated field reads and the static compiler emitted a spurious checkcast, throwing ClassCastException at runtime whenever the field held a different subtype. Members now push their own frame (methods and constructors, property and field initializers, object initializer blocks), so statement-level narrowing still flows within a member but can never survive into another; narrowing has no meaning past the member boundary. Intra-member flow typing (assert, if-branch) is unchanged. The checker-side leak predates Groovy 5 but was masked by codegen: StaticTypesTypeChooser resolved types from the declared target first until GROOVY-11375 (5.0.0-alpha-9) gave the expression-stamped inferred type priority, exposing the stale narrowing as a checkcast. That change is correct; the fix belongs here. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
