You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: jsonpatch.go
    path of file: ./repos/agones/vendor/gomodules.xyz/jsonpatch/v2
    
    the code of the file until where you have to start completion: package jsonpatch

import (
	"bytes"
	"encoding/json"
	"fmt"
	"reflect"
	"strings"
)

var errBadJSONDoc = fmt.Errorf("invalid JSON Document")

type JsonPatchOperation = Operation

type Operation struct {
	Operation string      `json:"op"`
	Path      string      `json:"path"`
	Value     interface{} `json:"value,omitempty"`
}

func (j *Operation) Json() string {
	b, _ := json.Marshal(j)
	return string(b)
}

func (j *Operation) MarshalJSON() ([]byte, error) {
	// Ensure f
    
func diff(a, b map[string]interface{}, path string, patch []Operation) ([]Operation, error) {
	for key, bv := range b {
		p := makePath(path, key)
		av, ok := a[key]
		// value was added
		if !ok {
			patch = append(patch, NewOperation("add", p, bv))
			continue
		}
		// Types are the same, compare values
		var err error
		patch, err = handleValues(av, bv, p, patch)
		if err != nil {
			return nil, err
		}
	}
	// Now add all deleted values as nil
	for key := range a {
		_, found := b[key]
		if !found {
			p := makePath(path, key)

			patch = append(patch, NewOperation("remove", p, nil))
		}
	}
	return patch, nil
}