LarryHu0217 opened a new pull request, #50837: URL: https://github.com/apache/arrow/pull/50837
## What changed - Run dictionary-to-dictionary casts through the cast kernel for zero-length inputs when the dictionary type changes. - Add a regression test that verifies both the widened index type and preserved dictionary values. The generic zero-length scalar fast path creates an empty output dictionary and discards categories that are still attached to the input array. Other zero-length scalar operations continue to use the existing fast path. ## Testing - `cpp/build-40128-auto/debug/arrow-compute-scalar-cast-test` (109 tests passed) - `clang-format --dry-run --Werror` on both changed files - `git diff --check` ## AI assistance I used Codex to help inspect the executor path, prepare the focused change, and draft the regression test. I reviewed the final diff, reproduced the failure before the fix, and ran the tests above locally. Closes #40128 -- 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]
