scovich opened a new pull request, #8208: URL: https://github.com/apache/arrow-rs/pull/8208
# Which issue does this PR close? - Closes https://github.com/apache/arrow-rs/issues/8152 # Rationale for this change When manipulating existing variant values (unshredding, removing fields, etc), the metadata column is already defined and already contains all necessary field ids. In fact, defining new/different field ids would require rewriting the bytes of those already-encoded variant values. We need a way to build variant values that rely on an existing metadata dictionary. # What changes are included in this PR? * `MetadataBuilder` is now a trait, and most methods that work with metadata builders now take `&mut dyn MetadataBuilder` instead of `&mut MetadataBuilder`. * The old `MetadataBuilder` struct is now `BasicMetadataBuilder` that implements `MetadataBuilder` * Define a `ReadOnlyMetadataBuilder` that wraps a `VariantMetadata` and which also implements `MetadataBuilder` * Update the `try_binary_search_range_by` helper method to be more general, so we can define an efficient `VariantMetadata::get_entry` that returns the field id for a given field name. # Are these changes tested? Existing tests cover the basic metadata builder. New tests added to cover the read-only metadata builder. # Are there any user-facing changes? The renamed `BasicMetadataBuilder` (breaking), the new `MetadataBuilder` trait (breaking), and the new `ReadOnlyMetadataBuilder`. -- 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
