[SPARK-56444][SQL] Fix equals/hashCode contract violations in BatchScanExec#55297
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anton5798 wants to merge 1 commit intoapache:masterfrom
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[SPARK-56444][SQL] Fix equals/hashCode contract violations in BatchScanExec#55297anton5798 wants to merge 1 commit intoapache:masterfrom
anton5798 wants to merge 1 commit intoapache:masterfrom
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…anExec ### What changes were proposed in this pull request? Fix two contract violations in `BatchScanExec.equals()`/`hashCode()`: 1. **Reflexivity violation**: `equals()` had a `this.batch != null` guard, so `x.equals(x)` returned `false` when `batch` was null (which happens after serialization round-trip since `scan` is `@transient`). 2. **hashCode inconsistency**: `hashCode()` did not include `keyGroupedPartitioning`, but `equals()` compared it — violating the contract that equal objects must have equal hash codes. ### Why are the changes needed? These violations can cause incorrect behavior when `BatchScanExec` instances are used in hash-based collections (e.g., `HashMap`, `HashSet`) or when comparing plans after serialization. ### Does this PR introduce _any_ user-facing change? No. ### How was this patch tested? Added unit tests in `SparkPlanSuite` verifying: - Reflexivity when `batch` is null - hashCode consistency with equals - hashCode sensitivity to `keyGroupedPartitioning` ### Was this patch authored or co-authored using generative AI tooling? Yes.
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aokolnychyi
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Apr 10, 2026
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LGTM, pending CI.
@anton5798, double check this PR that added this.batch != null in equals.
szehon-ho
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Apr 10, 2026
| keyGroupedPartitioning = Some(Seq(Literal(2))) | ||
| ) | ||
| assert(!exec1.equals(exec2)) | ||
| assert(exec1.hashCode() != exec2.hashCode()) |
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nit: would this fail with very low probability? should we remove?
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What changes were proposed in this pull request?
Fix two contract violations in
BatchScanExec.equals()/hashCode():equals()had athis.batch != nullguard, sox.equals(x)returnedfalsewhenbatchwas null (which happens after serialization round-trip sincescanis@transient).hashCode()did not includekeyGroupedPartitioning, butequals()compared it — violating the contract that equal objects must have equal hash codes.Why are the changes needed?
These violations can cause incorrect behavior when
BatchScanExecinstances are used in hash-based collections (e.g.,HashMap,HashSet) or when comparing plans after serialization.How was this patch tested?
Added unit tests in
SparkPlanSuiteverifying:batchis nullkeyGroupedPartitioningWas this patch authored or co-authored using generative AI tooling?
Yes.