jayzhan211 commented on code in PR #8569:
URL: https://github.com/apache/arrow-datafusion/pull/8569#discussion_r1429313655


##########
datafusion/physical-expr/src/array_expressions.rs:
##########
@@ -673,18 +673,72 @@ where
     )?))
 }
 
+/// If from_front is true, it is array_pop_front, otherwise array_pop_back
+fn general_pop_list<O: OffsetSizeTrait>(
+    array: &GenericListArray<O>,
+    from_front: bool,
+) -> Result<ArrayRef>
+where
+    i64: TryInto<O>,
+{
+    let (from_array, to_array) = if from_front {
+        let from_array = Int64Array::from(vec![2; array.len()]);
+        let to_array = Int64Array::from(
+            array
+                .iter()
+                .map(|arr| arr.map_or(0, |arr| arr.len() as i64))
+                .collect::<Vec<i64>>(),
+        );
+        (from_array, to_array)
+    } else {
+        let from_array = Int64Array::from(vec![1; array.len()]);
+        let to_array = Int64Array::from(
+            array
+                .iter()
+                .map(|arr| arr.map_or(0, |arr| arr.len() as i64 - 1))
+                .collect::<Vec<i64>>(),
+        );
+        (from_array, to_array)
+    };
+    general_array_slice::<O>(array, &from_array, &to_array)
+}
+
+/// array_pop_front SQL function
+pub fn array_pop_front(args: &[ArrayRef]) -> Result<ArrayRef> {
+    let array_data_type = args[0].data_type();
+    match array_data_type {
+        DataType::List(_) => {
+            let array = as_list_array(&args[0])?;
+            general_pop_list::<i32>(array, true)
+        }
+        DataType::LargeList(_) => {
+            let array = as_large_list_array(&args[0])?;
+            general_pop_list::<i64>(array, true)
+        }
+        _ => not_impl_err!(
+            "array_pop_front does not support type: {:?}",
+            array_data_type
+        ),
+    }
+}
+
 /// array_pop_back SQL function
 pub fn array_pop_back(args: &[ArrayRef]) -> Result<ArrayRef> {
-    let list_array = as_list_array(&args[0])?;
-    let from_array = Int64Array::from(vec![1; list_array.len()]);
-    let to_array = Int64Array::from(
-        list_array
-            .iter()
-            .map(|arr| arr.map_or(0, |arr| arr.len() as i64 - 1))
-            .collect::<Vec<i64>>(),
-    );
-    let args = vec![args[0].clone(), Arc::new(from_array), Arc::new(to_array)];
-    array_slice(args.as_slice())
+    let array_data_type = args[0].data_type();
+    match array_data_type {
+        DataType::List(_) => {
+            let array = as_list_array(&args[0])?;
+            general_pop_list::<i32>(array, false)
+        }
+        DataType::LargeList(_) => {
+            let array = as_large_list_array(&args[0])?;
+            general_pop_list::<i64>(array, false)
+        }
+        _ => not_impl_err!(

Review Comment:
   I think we should return internal or exec error, other types will not be 
implemented in the future, fixedsizelsit should be coerced to List.



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to