in Sources/SwiftSyntax/IncrementalParseTransition.swift [410:420]
mutating func advanceToNextNode(at position: AbsolutePosition) -> Bool {
repeat {
// if the node is fully before the requested position we can skip its children.
if node.endPosition > position {
if advanceToFirstChild() { continue }
}
if !advanceToNextSibling() { return false }
} while node.position < position
return node.position == position
}