empty.go

// This is free and unencumbered software released into the public domain.
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// software to the public domain. We make this dedication for the benefit
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// software under copyright law.
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package verkle

import "errors"

type Empty struct{}

var errDirectInsertIntoEmptyNode = errors.New("an empty node should not be inserted directly into")

func (Empty) Insert([]byte, []byte, NodeResolverFn) error {
	return errDirectInsertIntoEmptyNode
}

func (Empty) Delete([]byte, NodeResolverFn) (bool, error) {
	return false, errors.New("cant delete an empty node")
}

func (Empty) Get([]byte, NodeResolverFn) ([]byte, error) {
	return nil, nil
}

func (n Empty) Commit() *Point {
	return n.Commitment()
}

func (Empty) Commitment() *Point {
	var id Point
	id.SetIdentity()
	return &id
}

func (Empty) GetProofItems(Keylist, NodeResolverFn) (*ProofElements, []byte, []Stem, error) {
	return nil, nil, nil, errors.New("trying to produce a commitment for an empty subtree")
}

func (Empty) Serialize() ([]byte, error) {
	return nil, errors.New("can't encode empty node to RLP")
}

func (Empty) Copy() VerkleNode {
	return Empty(struct{}{})
}

func (Empty) toDot(string, string) string {
	return ""
}

func (Empty) setDepth(_ byte) {
	panic("should not be try to set the depth of an Empty node")
}

func (Empty) Hash() *Fr {
	return &FrZero
}