scovich opened a new pull request, #7915: URL: https://github.com/apache/arrow-rs/pull/7915
# Which issue does this PR close? Pathfinding related to the unshredding aspects of - https://github.com/apache/arrow-rs/issues/7715#issuecomment-3062004492 # Rationale for this change The variant shredding spec requires that the top-level variant metadata already contains all field names, whether those were shredded or not. That means an unshredding operation _must_ use the existing `VariantMetadata` for the column, and there's no point paying to build a new one. # What changes are included in this PR? Pathfinding change, where `MetadataBuilder` is renamed as `DefaultMetadataBuilder` that implements a new `MetadataBuilder` trait, which `VariantMetadata` can also implement. `VariantBuilder` then takes a type parameter for the specific `M: MetadataBuilder` that it uses. This change also requires several previously-infallible methods to become fallible, because attempting to insert a non-existent field name must fail. # Are these changes tested? Existing tests should cover the refactoring. A couple new tests lightly exercise the new read-only metadata. # Are there any user-facing changes? A whole bunch: * Methods become fallible * MetadataBuilder is now generic and may not `impl Default` any more * etc. -- 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: github-unsubscr...@arrow.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
