Samearth17 opened a new pull request, #6671: URL: https://github.com/apache/datafusion-comet/pull/6671
## Which issue does this PR close? Closes #6591. ## Rationale for this change Spark accepts casts to structs with repeated field names, but importing the native result through Java Arrow collapses fields by name and fails because the child count no longer matches. Comet should route this shape through fallback before it crosses Arrow FFI. ## What changes are included in this PR? - Make `CometCast.isSupported` reject target structs with duplicate field names. - Cover direct struct casts plus existing recursive array/map handling. - Verify a unique-name target remains natively compatible and the duplicate-name query reports the cast fallback reason. The repository's `implement-comet-expression` skill was used to follow the existing expression workflow. ## How are these changes tested? - `make core` - `./mvnw ... test -Dsuites=org.apache.comet.CometNativeCastSuite -Dtest=none` (190 passed, 0 failed, 8 ignored) - Focused duplicate-field regression on the merged head (1 passed) - Guard-removal mutation check (the focused regression failed as expected when the production guard was temporarily removed) - `make format-check` - `git diff --check` -- 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] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
