Handle hashing list of struct arrays

datafusion/common/src/hash_utils.rs

@@ -240,6 +240,33 @@ where
     Ok(())
 }
 
+fn hash_struct_array(
+    array: &StructArray,
+    random_state: &RandomState,
+    hashes_buffer: &mut [u64],
+) -> Result<()> {
+    let nulls = array.nulls();
+    let row_len = array.len();
+
+    let valid_row_indices: Vec<usize> = if let Some(nulls) = nulls {
+        nulls.valid_indices().collect()
+    } else {
+        (0..row_len).collect()
+    };
+
+    // Create hashes for each row that combines the hashes over all the column at that row.
+    let mut values_hashes = vec![0u64; row_len];
+    create_hashes(array.columns(), random_state, &mut values_hashes)?;
+
+    for i in valid_row_indices {
+        let hash = &mut hashes_buffer[i];
+        *hash = combine_hashes(*hash, values_hashes[i]);
+    }
+
+    Ok(())
+}
+
+
 /// Test version of `create_hashes` that produces the same value for
 /// all hashes (to test collisions)
 ///
@@ -327,6 +354,10 @@ pub fn create_hashes<'a>(
                 array => hash_dictionary(array, random_state, hashes_buffer, rehash)?,
                 _ => unreachable!()
             }
+            DataType::Struct(_) => {
+                let array = as_struct_array(array);
+                hash_struct_array(array, random_state, hashes_buffer)?;
+            }
             DataType::List(_) => {
                 let array = as_list_array(array);
                 hash_list_array(array, random_state, hashes_buffer)?;