[AURON #2368] Native arithmetic does not honor ANSI overflow semantics (e.g. negate of Int.MinValue)

[ShreyeshArangath]

Which issue does this PR close?

Closes #2368

Rationale for this change

Under ANSI mode, native unary minus wraps Int.MinValue and Long.MinValue instead of raising an arithmetic overflow like vanilla Spark. This also affects Spark 4.x where ANSI mode is enabled by default.

What changes are included in this PR?

1. Adds a native SparkNegativeExpr with checked negation for signed integral types when ANSI mode is enabled.
2. Passes Spark ANSI configuration to the native expression and honors Spark version defaults.
3. Uses DataFusion negative expression behavior for non-ANSI and non-integral values.
4. Adds coverage for int and long overflow, non-ANSI wrapping, native execution, and Spark default ANSI behavior.

Are there any user-facing changes?

Correctness fix. Native unary minus now follows Spark ANSI overflow semantics.

How was this patch tested?

Full local build and test matrix for Spark 3.0 through Spark 4.1, including the configured Scala and JDK combinations.

Was this patch authored or co-authored using generative AI tooling?

• Yes
• No

Generated-by: Copilot and GPT 5.6

[Copilot]

Pull request overview

This PR fixes a correctness gap where native unary minus (negative(x) / -x) did not follow Spark ANSI overflow semantics (notably Int.MinValue / Long.MinValue) by propagating Spark’s ANSI setting into the native plan and performing checked negation for signed integral types when ANSI is enabled.

Changes:

• Adds a native SparkNegativeExpr that performs checked negation for signed integral types when ANSI mode is enabled; otherwise delegates to DataFusion’s NegativeExpr.
• Plumbs Spark’s ANSI configuration through the Spark extension → protobuf → native planner path.
• Expands Spark-side test coverage for ANSI overflow (int/long), non-ANSI wrapping, native execution, and Spark’s default ANSI behavior.

Reviewed changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
spark-extension/src/main/scala/org/apache/spark/sql/auron/NativeConverters.scala	Passes SQLConf.get.ansiEnabled into the protobuf negative node.
spark-extension-shims-spark/src/test/scala/org/apache/auron/AuronExpressionSuite.scala	Adds Spark tests covering ANSI overflow for int/long, non-ANSI behavior, and default ANSI behavior.
native-engine/datafusion-ext-exprs/src/spark_negative.rs	Introduces SparkNegativeExpr with ANSI checked negation for integral types plus unit tests.
native-engine/datafusion-ext-exprs/src/lib.rs	Exposes the new spark_negative module.
native-engine/auron-planner/src/planner.rs	Switches negative planning from DataFusion NegativeExpr to SparkNegativeExpr, consuming ansi_enabled.
native-engine/auron-planner/proto/auron.proto	Extends PhysicalNegativeNode to carry bool ansi_enabled.

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