From a48ced7c2a9b8b2137a717d8fc8059d65f6dd3cc Mon Sep 17 00:00:00 2001
From: Andres Taylor <andres@planetscale.com>
Date: Tue, 10 Dec 2024 12:15:04 +0100
Subject: [PATCH] comment

Signed-off-by: Andres Taylor <andres@planetscale.com>
---
 go/vt/sqlparser/{cow.go => copy_on_write.go} | 3 +++
 1 file changed, 3 insertions(+)
 rename go/vt/sqlparser/{cow.go => copy_on_write.go} (94%)

diff --git a/go/vt/sqlparser/cow.go b/go/vt/sqlparser/copy_on_write.go
similarity index 94%
rename from go/vt/sqlparser/cow.go
rename to go/vt/sqlparser/copy_on_write.go
index be376f84403..4a355c0c9b8 100644
--- a/go/vt/sqlparser/cow.go
+++ b/go/vt/sqlparser/copy_on_write.go
@@ -53,6 +53,9 @@ func CopyOnRewrite(
 	return out
 }
 
+// CopyAndReplaceExpr traverses a syntax tree recursively, starting with root,
+// and replaceFn is called for each node that is an Expr. If replaceFn returns
+// true, the node is replaced with the returned node.
 func CopyAndReplaceExpr(node SQLNode, replaceFn func(node Expr) (Expr, bool)) SQLNode {
 	var replace Expr
 	pre := func(node, _ SQLNode) bool {