Minor Description
CoalesceFunctionNode manually iterates over argumentsList (a ValueNodeList) in acceptChildren(), preprocess(), remapColumnReferencesToExpressions() and isEquivalent(). ValueNodeList has helper methods for the first three of those, and those helper methods should be used instead to simplify the code. There is no helper method for isEquivalent(), but since very similar code is also found in the isEquivalent() methods of BinaryListOperatorNode and ConditionalNode, we should add a new helper and use it in those classes too.