fix(apollo-forest-run): apply structural diffs to divergent chunks#695
Merged
Conversation
Promote nested object and list differences to replacements for null chunks and fillers for missing chunks, while preserving genuine structural mismatch invariants. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 27f20a2a-77b3-4142-89c2-bc2dc2b5f2c5
📊 Benchmark Analysis Report✅ No significant performance changes detected Threshold: 5% change Updated: 2026-07-17T11:25:20.962Z |
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 27f20a2a-77b3-4142-89c2-bc2dc2b5f2c5
vladar
changed the title
added 3 commits
July 16, 2026 17:54
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 27f20a2a-77b3-4142-89c2-bc2dc2b5f2c5
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 27f20a2a-77b3-4142-89c2-bc2dc2b5f2c5
Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 27f20a2a-77b3-4142-89c2-bc2dc2b5f2c5
vladar
marked this pull request as ready for review
July 17, 2026 11:19
vejrj
approved these changes
Jul 17, 2026
sergey-stoyan
approved these changes
Jul 17, 2026
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
3 participants
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
Why
A node of the graph can contain divergent representations of the same value: an object or list in one chunk and
nullor missing data in another. Applying the shared structural difference to every representation then fails update invariants. PR #686 demonstrated these failures, but relaxing the invariants leaves stale chunks behind.The earlier reconciliation approach fixed correctness but imposed common-path diffing and allocation costs. This version keeps the exceptional handling localized to the existing update invariant branches.
Approach
newValueonObjectDifferenceandCompositeListDifferenceonly when diffing exits with an actual or incomplete difference. Clean comparisons remain allocation-free.CompositeNullorCompositeUndefined.CompositeUndefinedcan be filled.The regression scenarios from #686 now require complete, consistently updated results across every affected query view.
Validation
yarn workspace @graphitation/apollo-forest-run typesyarn lintPerformance validation is left to the ForestRun benchmark workflow in CI.