Function ExceedsDepth

common/ast/navigable.go:191–205

ExceedsDepth determines whether the AST contains expressions nested deeper than the specified maxDepth. The root expression has depth 0, so a maxDepth of 250 permits expressions nested up to and including 250 levels deep. The traversal is bounded: it descends at most maxDepth+1 levels, so it remain

(a *AST, maxDepth int)

// adversarially deep inputs that could otherwise exhaust the Go stack during later checking or
// planning. A non-positive maxDepth disables the check and returns false.
func ExceedsDepth(a *AST, maxDepth int) bool {
	if a == nil || maxDepth <= 0 {
		return false
	}
	exceedsDepth := false
	visitor := NewExprVisitor(func(e Expr) {
		if nav, ok := e.(NavigableExpr); ok && nav.Depth() >= maxDepth {
			exceedsDepth = true
		}
	})
	// Bound the walk to maxDepth+1 levels so it never recurses past the first level that exceeds
	// the limit, keeping the check itself safe on the deep inputs it guards against.
	visit(NavigateAST(a), visitor, postOrder, 0, maxDepth+1)
	return exceedsDepth
}

type visitOrder int