use array.filter() instead of filter(array) compute

Signed-off-by: Connor Tsui <connor.tsui20@gmail.com>

Author: connortsui20

encodings/fsst/src/tests.rs

@@ -88,7 +88,7 @@ fn test_fsst_array_ops() {
     let mask = Mask::from_iter([false, true, true]);
 
     let fsst_filtered = filter(&fsst_array, &mask).unwrap();
-    assert!(fsst_filtered.is::<FSSTVTable>());
+
     assert_eq!(fsst_filtered.len(), 2);
     assert_nth_scalar!(
         fsst_filtered,

encodings/sparse/src/compute/mod.rs

@@ -58,7 +58,6 @@ mod test {
     use vortex_scalar::Scalar;
 
     use crate::SparseArray;
-    use crate::SparseVTable;
 
     #[fixture]
     fn array() -> ArrayRef {
@@ -79,13 +78,18 @@ mod test {
         let mask = Mask::from_iter(predicate);
 
         let filtered_array = filter(&array, &mask).unwrap();
-        let filtered_array = filtered_array.as_::<SparseVTable>();
 
-        assert_eq!(filtered_array.len(), 1);
-        assert_arrays_eq!(
-            filtered_array.patches().indices(),
-            PrimitiveArray::from_iter([0u64])
-        );
+        // Construct expected SparseArray: index 2 was kept, which had value 33.
+        // The new index is 0 (since it's the only element).
+        let expected = SparseArray::try_new(
+            buffer![0u64].into_array(),
+            PrimitiveArray::new(buffer![33_i32], Validity::AllValid).into_array(),
+            1,
+            Scalar::null_typed::<i32>(),
+        )
+        .unwrap();
+
+        assert_arrays_eq!(filtered_array, expected);
     }
 
     #[test]
@@ -101,12 +105,20 @@ mod test {
         .into_array();
 
         let filtered_array = filter(&array, &mask).unwrap();
-        let filtered_array = filtered_array.as_::<SparseVTable>();
 
-        assert_arrays_eq!(
-            filtered_array.patches().indices(),
-            PrimitiveArray::from_iter([1u64, 3])
-        );
+        // Original indices 0, 3, 6 with values 33, 44, 55.
+        // Mask keeps indices 1, 3, 5, 6 -> new indices 0, 1, 2, 3.
+        // Index 3 (value 44) maps to new index 1.
+        // Index 6 (value 55) maps to new index 3.
+        let expected = SparseArray::try_new(
+            buffer![1u64, 3].into_array(),
+            PrimitiveArray::new(buffer![44_i32, 55], Validity::AllValid).into_array(),
+            4,
+            Scalar::null_typed::<i32>(),
+        )
+        .unwrap();
+
+        assert_arrays_eq!(filtered_array, expected);
     }
 
     #[rstest]

vortex-array/src/arrays/assertions.rs

@@ -26,6 +26,26 @@ macro_rules! assert_nth_scalar {
     };
 }
 
+/// Asserts that the scalar at position `$n` in array `$arr` is null.
+///
+/// # Example
+///
+/// ```ignore
+/// let arr = PrimitiveArray::from_option_iter([Some(1), None, Some(3)]);
+/// assert_nth_scalar_null!(arr, 1);
+/// ```
+#[macro_export]
+macro_rules! assert_nth_scalar_is_null {
+    ($arr:expr, $n:expr) => {
+        assert!(
+            $arr.scalar_at($n).unwrap().is_null(),
+            "expected scalar at index {} to be null, but was {:?}",
+            $n,
+            $arr.scalar_at($n).unwrap()
+        );
+    };
+}
+
 #[macro_export]
 macro_rules! assert_arrays_eq {
     ($left:expr, $right:expr) => {{