fix

Signed-off-by: Joe Isaacs <joe.isaacs@live.co.uk>

Author: joseph-isaacs

encodings/alp/src/alp_rd/array.rs

@@ -26,7 +26,6 @@ use vortex_array::patches::PatchesMetadata;
 use vortex_array::serde::ArrayChildren;
 use vortex_array::stats::ArrayStats;
 use vortex_array::stats::StatsSetRef;
-use vortex_array::validity::Validity;
 use vortex_array::vtable;
 use vortex_array::vtable::ArrayId;
 use vortex_array::vtable::VTable;
@@ -41,7 +40,6 @@ use vortex_error::vortex_bail;
 use vortex_error::vortex_ensure;
 use vortex_error::vortex_err;
 use vortex_error::vortex_panic;
-use vortex_mask::Mask;
 use vortex_session::VortexSession;
 
 use crate::alp_rd::kernel::PARENT_KERNELS;
@@ -302,18 +300,6 @@ impl VTable for ALPRD {
 
         let left_parts_dict = array.left_parts_dictionary();
 
-        let nullability = array.dtype().nullability();
-        let validity = if nullability == Nullability::NonNullable {
-            Validity::NonNullable
-        } else {
-            let mask = array
-                .left_parts()
-                .validity()?
-                .to_array(array.len())
-                .execute::<Mask>(ctx)?;
-            Validity::from_mask(mask, nullability)
-        };
-
         let decoded_array = if array.is_f32() {
             PrimitiveArray::new(
                 alp_rd_decode::<f32>(
@@ -324,7 +310,7 @@ impl VTable for ALPRD {
                     array.left_parts_patches(),
                     ctx,
                 )?,
-                validity,
+                array.left_parts().validity()?.clone(),
             )
         } else {
             PrimitiveArray::new(
@@ -336,7 +322,7 @@ impl VTable for ALPRD {
                     array.left_parts_patches(),
                     ctx,
                 )?,
-                validity,
+                array.left_parts().validity()?.clone(),
             )
         };
 

encodings/alp/src/alp_rd/mod.rs

@@ -306,8 +306,7 @@ pub fn alp_rd_decode<T: ALPRDFloat>(
 
     if let Some(patches) = left_parts_patches {
         for code in left_parts.iter_mut() {
-            // SAFETY: The encoder guarantees all codes are valid indices into left_parts_dict.
-            *code = unsafe { *left_parts_dict.get_unchecked(*code as usize) };
+            *code = left_parts_dict[*code as usize];
         }
         let indices = patches.indices().clone().execute::<PrimitiveArray>(ctx)?;
         let patch_values = patches.values().clone().execute::<PrimitiveArray>(ctx)?;