bhollis-dbx commented on code in PR #58800:
URL: https://github.com/apache/spark/pull/58800#discussion_r4075557757
##########
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/trees/TreeNode.scala:
##########
@@ -745,10 +763,52 @@ abstract class TreeNode[BaseType <: TreeNode[BaseType]]
* Returns a copy of this node where `f` has been applied to all the nodes
in `children`.
*/
def mapChildren(f: BaseType => BaseType): BaseType = {
- if (containsChild.nonEmpty) {
- withNewChildren(children.map(f))
- } else {
+ val oldChildren = children
+ if (oldChildren.isEmpty) return this
+
+ // Single pass, allocating nothing until `f` returns a distinct instance
for some child.
Review Comment:
Updated the comment to state one f call per child and deferred buffer
allocation with prefix backfill.
--
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]
---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]
