Feature: add struct OperatorVTable::bind (#5105)

Tracking Issue: #5028

---------

Signed-off-by: Connor Tsui <[email protected]>
Signed-off-by: Nicholas Gates <[email protected]>
Co-authored-by: Nicholas Gates <[email protected]>

Author: connortsui20

vortex-array/src/arrays/struct_/vtable/mod.rs

@@ -8,7 +8,7 @@ use crate::{EncodingId, EncodingRef, vtable};
 mod array;
 mod canonical;
 mod operations;
-mod pipeline;
+mod operator;
 mod serde;
 mod validity;
 mod visitor;

vortex-array/src/arrays/struct_/vtable/operator.rs

@@ -0,0 +1,190 @@
+// SPDX-License-Identifier: Apache-2.0
+// SPDX-FileCopyrightText: Copyright the Vortex contributors
+
+use std::sync::Arc;
+
+use vortex_error::VortexResult;
+use vortex_vector::{StructVector, Vector};
+
+use crate::ArrayRef;
+use crate::arrays::{StructArray, StructVTable};
+use crate::execution::{BatchKernelRef, BindCtx, kernel};
+use crate::vtable::{OperatorVTable, ValidityHelper};
+
+impl OperatorVTable<StructVTable> for StructVTable {
+    fn bind(
+        array: &StructArray,
+        selection: Option<&ArrayRef>,
+        ctx: &mut dyn BindCtx,
+    ) -> VortexResult<BatchKernelRef> {
+        // Bind all child field arrays with the selection.
+        let field_kernels: Vec<_> = array
+            .fields()
+            .iter()
+            .map(|field| ctx.bind(field, selection))
+            .collect::<VortexResult<_>>()?;
+        let validity = ctx.bind_validity(array.validity(), array.len(), selection)?;
+
+        Ok(kernel(move || {
+            // Execute all child field kernels.
+            let fields: Vec<Vector> = field_kernels
+                .into_iter()
+                .map(|k| k.execute())
+                .collect::<VortexResult<_>>()?;
+            let validity_mask = validity.execute()?;
+
+            Ok(StructVector::try_new(Arc::new(fields.into_boxed_slice()), validity_mask)?.into())
+        }))
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use std::sync::Arc;
+
+    use vortex_dtype::{FieldNames, PTypeDowncast};
+    use vortex_vector::VectorOps;
+
+    use crate::IntoArray;
+    use crate::arrays::{BoolArray, PrimitiveArray, StructArray};
+    use crate::validity::Validity;
+
+    #[test]
+    fn test_struct_operator_basic() {
+        // Create a struct array with two fields: integers and booleans.
+        let int_field = PrimitiveArray::from_iter([1i32, 2, 3, 4, 5]);
+        let bool_field = BoolArray::from_iter([true, false, true, false, true]);
+
+        let struct_array = StructArray::try_new(
+            FieldNames::from(["ints", "bools"]),
+            vec![int_field.into_array(), bool_field.into_array()],
+            5,
+            Validity::AllValid,
+        )
+        .unwrap();
+
+        // Execute without selection.
+        let result = struct_array.execute().unwrap();
+        assert_eq!(result.len(), 5);
+
+        // Verify the struct vector fields.
+        let struct_vector = result.as_struct();
+        let fields = struct_vector.fields();
+        assert_eq!(fields.len(), 2);
+
+        // Verify the integer field values match the original.
+        let int_vector = fields[0].as_primitive().clone().into_i32();
+        assert_eq!(int_vector.elements().as_slice(), &[1, 2, 3, 4, 5]);
+
+        // Verify the boolean field values match the original.
+        let bool_vector = fields[1].as_bool();
+        let bool_values: Vec<bool> = (0..5).map(|i| bool_vector.bits().value(i)).collect();
+        assert_eq!(bool_values, vec![true, false, true, false, true]);
+    }
+
+    #[test]
+    fn test_struct_operator_with_mask() {
+        // Create a struct array with two fields.
+        let int_field = PrimitiveArray::from_iter([10i32, 20, 30, 40, 50, 60]);
+        let bool_field = BoolArray::from_iter([true, false, true, false, true, false]);
+
+        let struct_array = StructArray::try_new(
+            FieldNames::from(["numbers", "flags"]),
+            vec![int_field.into_array(), bool_field.into_array()],
+            6,
+            Validity::AllValid,
+        )
+        .unwrap();
+
+        // Create a selection mask that selects indices 0, 2, 4 (alternating pattern).
+        let selection = BoolArray::from_iter([true, false, true, false, true, false]).into_array();
+
+        // Execute with selection mask.
+        let result = struct_array
+            .execute_with_selection(Some(&Arc::new(selection)))
+            .unwrap();
+
+        // Verify the result has the filtered length.
+        assert_eq!(result.len(), 3);
+
+        // Verify the struct vector fields.
+        let struct_vector = result.as_struct();
+        let fields = struct_vector.fields();
+        assert_eq!(fields.len(), 2);
+
+        // Verify the integer field has the correct filtered values (indices 0, 2, 4).
+        let int_vector = fields[0].as_primitive().clone().into_i32();
+        assert_eq!(int_vector.elements().as_slice(), &[10, 30, 50]);
+
+        // Verify the boolean field has the correct filtered values (indices 0, 2, 4).
+        let bool_vector = fields[1].as_bool();
+        let bool_values: Vec<bool> = (0..3).map(|i| bool_vector.bits().value(i)).collect();
+        assert_eq!(bool_values, vec![true, true, true]);
+    }
+
+    #[test]
+    fn test_struct_operator_null_handling() {
+        // Create fields with nulls.
+        let int_field = PrimitiveArray::from_option_iter([
+            Some(100i32),
+            None,
+            Some(200),
+            Some(300),
+            None,
+            Some(400),
+        ]);
+
+        // Create bool field with its own validity.
+        let bool_array = BoolArray::from_iter([true, false, true, false, true, false]);
+        let bool_validity = Validity::from_iter([true, true, false, true, true, false]);
+        let bool_field = BoolArray::from_bit_buffer(bool_array.bit_buffer().clone(), bool_validity);
+
+        // Create struct with its own validity mask (rows 1 and 4 are null).
+        let struct_validity = Validity::from_iter([true, false, true, true, false, true]);
+
+        let struct_array = StructArray::try_new(
+            FieldNames::from(["values", "flags"]),
+            vec![int_field.into_array(), bool_field.into_array()],
+            6,
+            struct_validity,
+        )
+        .unwrap();
+
+        // Create a selection mask that selects indices 0, 1, 2, 4, 5.
+        let selection = BoolArray::from_iter([true, true, true, false, true, true]).into_array();
+
+        // Execute with selection mask.
+        let result = struct_array
+            .execute_with_selection(Some(&Arc::new(selection)))
+            .unwrap();
+
+        assert_eq!(result.len(), 5);
+
+        // Verify the struct vector fields.
+        let struct_vector = result.as_struct();
+        let fields = struct_vector.fields();
+        assert_eq!(fields.len(), 2);
+
+        // Verify integer field has the correct filtered values with nulls.
+        // Selected indices: 0, 1, 2, 4, 5 from [Some(100), None, Some(200), Some(300), None, Some(400)].
+        let int_vector = fields[0].as_primitive().clone().into_i32();
+        let int_values: Vec<Option<i32>> = (0..5).map(|i| int_vector.get(i).copied()).collect();
+        assert_eq!(
+            int_values,
+            vec![Some(100), None, Some(200), None, Some(400)]
+        );
+
+        // Verify boolean field values.
+        // Selected indices: 0, 1, 2, 4, 5 from [T, F, T, F, T, F].
+        let bool_vector = fields[1].as_bool();
+        let bool_values: Vec<bool> = (0..5).map(|i| bool_vector.bits().value(i)).collect();
+        assert_eq!(bool_values, vec![true, false, true, true, false]);
+
+        // Verify the struct-level validity is correctly propagated.
+        // Original struct validity: [T, F, T, T, F, T]
+        // Selected indices: 0, 1, 2, 4, 5 -> validity: [T, F, T, F, T].
+        let validity_mask = struct_vector.validity();
+        let struct_validity_values: Vec<bool> = (0..5).map(|i| validity_mask.value(i)).collect();
+        assert_eq!(struct_validity_values, vec![true, false, true, false, true]);
+    }
+}