From 67efcce553ad76a64660138fe2b495aa1ab45a93 Mon Sep 17 00:00:00 2001
From: Matt Katz <mhkatz97@gmail.com>
Date: Tue, 21 Jul 2026 13:17:06 -0700
Subject: [PATCH] mask listview preserves zctl

Signed-off-by: Matt Katz <mhkatz97@gmail.com>
---
 vortex-array/src/arrays/masked/execute.rs |  2 ++
 vortex-array/src/arrays/masked/tests.rs   | 21 +++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/vortex-array/src/arrays/masked/execute.rs b/vortex-array/src/arrays/masked/execute.rs
index c4173dd0cf6..0de8be7321e 100644
--- a/vortex-array/src/arrays/masked/execute.rs
+++ b/vortex-array/src/arrays/masked/execute.rs
@@ -110,6 +110,7 @@ fn mask_validity_varbinview(
 fn mask_validity_listview(array: ListViewArray, validity: Validity) -> VortexResult<ListViewArray> {
     let new_validity = Validity::and(array.validity()?, validity)?;
     // SAFETY: We're only changing validity, not the data structure
+    let is_zctl = array.is_zero_copy_to_list();
     Ok(unsafe {
         ListViewArray::new_unchecked(
             array.elements().clone(),
@@ -117,6 +118,7 @@ fn mask_validity_listview(array: ListViewArray, validity: Validity) -> VortexRes
             array.sizes().clone(),
             new_validity,
         )
+        .with_zero_copy_to_list(is_zctl)
     })
 }
 
diff --git a/vortex-array/src/arrays/masked/tests.rs b/vortex-array/src/arrays/masked/tests.rs
index 842599bfa52..92ec4eb474f 100644
--- a/vortex-array/src/arrays/masked/tests.rs
+++ b/vortex-array/src/arrays/masked/tests.rs
@@ -10,6 +10,7 @@ use crate::Canonical;
 use crate::IntoArray;
 use crate::VortexSessionExecute;
 use crate::array_session;
+use crate::arrays::ListViewArray;
 use crate::arrays::PrimitiveArray;
 use crate::assert_arrays_eq;
 use crate::dtype::DType;
@@ -140,3 +141,23 @@ fn test_masked_child_preserves_length(#[case] validity: Validity) {
             .unwrap(),
     );
 }
+
+#[test]
+fn masked_listview_execute_preserves_zctl_true() -> VortexResult<()> {
+    // Masking only intersects validity, so the zero-copy-to-list survives
+    // execution.
+    let elements = PrimitiveArray::from_iter([1i32, 2, 3]).into_array();
+    let offsets = PrimitiveArray::from_iter([0i32, 2]).into_array();
+    let sizes = PrimitiveArray::from_iter([2i32, 1]).into_array();
+    let list_view = unsafe {
+        ListViewArray::new_unchecked(elements, offsets, sizes, Validity::NonNullable)
+            .with_zero_copy_to_list(true)
+    };
+
+    let masked = MaskedArray::try_new(list_view.into_array(), Validity::from_iter([true, false]))?;
+    let canonical = masked
+        .into_array()
+        .execute::<Canonical>(&mut array_session().create_execution_ctx())?;
+    assert!(canonical.into_listview().is_zero_copy_to_list());
+    Ok(())
+}