Error message. "Props with type Object/Array must use a factory function to return the default value."

A factory function in props looks like this:

props: {    exampleDefaultObject: {        type: Object,        default() {            return {}        }    },    exampleDefaultArray: {        type: Array,        default() {            return []        }    }},

or in ES6:

props: {    exampleDefaultObject: {        type: Object,        default: () => ({})    },    exampleDefaultArray: {        type: Array,        default: () => []    }},

(for people who come here looking for an explanation of the error in the question 'props with type object/array must use a factory function to return the default value')

Note that when returning an object in an es6 arrow function, you need the parentheses: () => ({}) instead of () => {}

according to your console warn, i find the error

https://github.com/holiber/sl-vue-tree/blob/master/src/sl-vue-tree.js#L30

try to fix it like this:

multiselectKey: {  type: [String, Array],  default: function () {    return ['ctrlKey', 'metaKey']  },  validator: function (value) {    let allowedKeys = ['ctrlKey', 'metaKey', 'altKey'];    let multiselectKeys = Array.isArray(value) ? value : [value];    multiselectKeys = multiselectKeys.filter(keyName => allowedKeys.indexOf(keyName ) !== -1);    return !!multiselectKeys.length;  }},

the component default value must use a factory function to return!

try it and hope it can help you

these cases require a function than produce the default value, not an object or array:

obj_param:{        type:Object,        default:()=>{}},array_param:{        type:Array,        default:()=>[]},

this is for performance reasons, since the function is called only if needed (no value so use default), while the direct value would be instantiated everytime the component is used