(datafusion) branch main updated: fix nth_value window function negates i64::MIN (#22304)

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github-merge-queue[bot] pushed a commit to branch main
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The following commit(s) were added to refs/heads/main by this push:
     new e2db7668f6 fix nth_value window function negates i64::MIN (#22304)
e2db7668f6 is described below

commit e2db7668f621aafb1a09aacdbdb8b0bd37b0caa3
Author: Zhen Chen <cz...@163.com>
AuthorDate: Wed Jun 3 14:48:29 2026 +0800

    fix nth_value window function negates i64::MIN (#22304)
    
    ## Which issue does this PR close?
    
    - Closes #22222.
    
    ## Rationale for this change
    
    `nth_value` could panic at execution time when called with `i64::MIN` as
    the `n` argument. The implementation supports negative `n` for reverse
    indexing and negated the value internally, but negating `i64::MIN`
    overflows. This caused a runtime panic instead of returning a normal
    DataFusion error for invalid input.
    
    ## What changes are included in this PR?
    
    This PR adds validation for the second argument of `nth_value` so that
    `i64::MIN` is rejected before any negation occurs. Instead of panicking
    during execution, the function now returns a regular execution error.
    
    This PR also adds regression coverage at two levels:
    - a unit test for the `nth_value` window function implementation
    - a sqllogictest case covering the SQL query shape that previously
    triggered the panic
    
    ## Are these changes tested?
    
    Yes.
    
    The change is covered by:
    1. a focused unit test in the window function implementation
    2. a SQL logic test in `window.slt`
    
    Validated with:
    1. `cargo test -p datafusion-functions-window nth_value --lib`
    2. `cargo test -p datafusion-sqllogictest --test sqllogictests window`
    
    ## Are there any user-facing changes?
    
    Yes. Queries that previously panicked when calling `nth_value(...,
    -9223372036854775808)` now return a proper execution error instead.
---
 datafusion/functions-window/src/nth_value.rs  | 29 +++++++++++++++++++++++++++
 datafusion/sqllogictest/test_files/window.slt |  4 ++++
 2 files changed, 33 insertions(+)

diff --git a/datafusion/functions-window/src/nth_value.rs b/datafusion/functions-window/src/nth_value.rs
index 437b4ecdb3..df72377216 100644
--- a/datafusion/functions-window/src/nth_value.rs
+++ b/datafusion/functions-window/src/nth_value.rs
@@ -125,6 +125,14 @@ impl NthValue {
     }
 }
 
+fn validate_nth_value_n(n: i64) -> Result<i64> {
+    if n == i64::MIN {
+        return exec_err!("The second argument of nth_value must not be i64::MIN");
+    }
+
+    Ok(n)
+}
+
 static FIRST_VALUE_DOCUMENTATION: LazyLock<Documentation> = LazyLock::new(|| {
     Documentation::builder(
         DOC_SECTION_ANALYTICAL,
@@ -287,6 +295,7 @@ impl WindowUDFImpl for NthValue {
         .map(|v| get_signed_integer(&v))
         {
             Some(Ok(n)) => {
+                let n = validate_nth_value_n(n)?;
                 if partition_evaluator_args.is_reversed() {
                     -n
                 } else {
@@ -660,4 +669,24 @@ mod tests {
         )?;
         Ok(())
     }
+
+    #[test]
+    fn nth_value_i64_min_returns_error() {
+        let expr = Arc::new(Column::new("c3", 0)) as Arc<dyn PhysicalExpr>;
+        let n_value = Arc::new(Literal::new(ScalarValue::Int64(Some(i64::MIN))))
+            as Arc<dyn PhysicalExpr>;
+
+        let err = NthValue::nth()
+            .partition_evaluator(PartitionEvaluatorArgs::new(
+                &[expr, n_value],
+                &[Field::new("f", DataType::Int32, true).into()],
+                false,
+                false,
+            ))
+            .unwrap_err();
+
+        assert!(err.to_string().starts_with(
+            "Execution error: The second argument of nth_value must not be i64::MIN"
+        ));
+    }
 }
diff --git a/datafusion/sqllogictest/test_files/window.slt b/datafusion/sqllogictest/test_files/window.slt
index 1c614f6a22..bc2f1bfcbc 100644
--- a/datafusion/sqllogictest/test_files/window.slt
+++ b/datafusion/sqllogictest/test_files/window.slt
@@ -1215,6 +1215,10 @@ NULL 3917
 -1114 -1114
 15673 15673
 
+statement error Execution error: The second argument of nth_value must not be i64::MIN
+SELECT nth_value(x, -9223372036854775808) OVER (ORDER BY x)
+FROM (VALUES (1)) AS t(x);
+
 
 
 


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