Gap
FFI_WindowUDF in datafusion/ffi/src/udwf/mod.rs does not plumb several defaulted methods of WindowUDFImpl. Producer overrides are silently lost on the consumer side.
Missing methods
simplifyexpressionsreverse_exprdocumentation
Why it matters
Severity: important. expressions() selects which physical expressions reach the PartitionEvaluator — silent fallback can change window-function semantics. simplify and reverse_expr are planner hooks. documentation is cosmetic but cheap to add.
Implementation notes
- Plumb each as a plain
unsafe extern \"C\" fn; wrapper body calls the trait method on inner Arc<dyn WindowUDFImpl> and dispatch handles override-or-default.
expressions returns Vec<Arc<dyn PhysicalExpr>> — relies on the existing FFI_PhysicalExpr plumbing.simplify / reverse_expr ship Expr — require the embedded FFI_LogicalExtensionCodec.- Layout change →
api change label, target main only, no back-port to branch-<major>.
- Add unit tests (local-bypass +
mock_foreign_marker_id forced-foreign) and integration tests under datafusion/ffi/tests/.
Generated from an audit performed for PR #22327 (datafusion-ffi agent skill). If a PR addressing this finds any item to be a false positive (e.g., a method intentionally omitted for a documented reason), please also propose an update to the datafusion-ffi skill so future audits do not re-flag it.
Gap
FFI_WindowUDFindatafusion/ffi/src/udwf/mod.rsdoes not plumb several defaulted methods ofWindowUDFImpl. Producer overrides are silently lost on the consumer side.Missing methods
simplifyexpressionsreverse_exprdocumentationWhy it matters
Severity: important.
expressions()selects which physical expressions reach thePartitionEvaluator— silent fallback can change window-function semantics.simplifyandreverse_exprare planner hooks.documentationis cosmetic but cheap to add.Implementation notes
unsafe extern \"C\" fn; wrapper body calls the trait method on innerArc<dyn WindowUDFImpl>and dispatch handles override-or-default.expressionsreturnsVec<Arc<dyn PhysicalExpr>>— relies on the existingFFI_PhysicalExprplumbing.simplify/reverse_exprshipExpr— require the embeddedFFI_LogicalExtensionCodec.api changelabel, targetmainonly, no back-port tobranch-<major>.mock_foreign_marker_idforced-foreign) and integration tests underdatafusion/ffi/tests/.Generated from an audit performed for PR #22327 (datafusion-ffi agent skill). If a PR addressing this finds any item to be a false positive (e.g., a method intentionally omitted for a documented reason), please also propose an update to the
datafusion-ffiskill so future audits do not re-flag it.