Repository navigation
fix(arrow-data): avoid unnecessary FixedSizeList null expansion - #12121
Open
WaterWhisperer wants to merge 2 commits into
Open
WaterWhisperer wants to merge 2 commits into
WaterWhisperer wants to merge 2 commits into
Conversation
github-actions
Bot
added
arrow-core
Rich-T-kid
reviewed
Nov 8, 2026
Rich-T-kid
left a comment
Rich-T-kid
left a comment
Contributor
There was a problem hiding this comment.
can we add a regression test for this behavior
Contributor
Author
sure |
Rich-T-kid
requested changes
Nov 10, 2026
| @@ -0,0 +1,101 @@ | |||
| // SPDX-License-Identifier: Apache-2.0 | |||
Contributor
There was a problem hiding this comment.
this shouldn't be in its own file, add it to the test section of arrow-data/src/data.rs
This branch has not been deployed
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Which issue does this PR close?
Rationale for this change
FixedSizeList null validation can allocate a large parent bitmap even when the visible child range contains no nulls.
What changes are included in this PR?
Skip expansion when the visible child range has no nulls. Use
try_expandto returnMemoryErrorif a required expansion fails.Are these changes tested?
Yes. Existing tests cover null masking and sliced child ranges. The full workspace test suite and Clippy passed locally.
A local allocation probe using valid empty Struct children confirmed zero allocation when expansion is unnecessary, and
MemoryErrorinstead of a panic when a required bitmap allocation is rejected. The probe is not included in this PR.Are there any significant user-facing changes?
No.
AI usage disclosure
OpenAI Codex assisted with the implementation and local validation. I reviewed and verified the changes.