@atlaskit/editor-core/src/json-schema/json-schema-nodes/enum-schema-node.ts

A package contains Atlassian editor core functionality

import SchemaNode from './schema-node';

export type EnumTypes = string | number | boolean;

export default class EnumSchemaNode extends SchemaNode {
  values: Set<EnumTypes>;

  constructor(values: EnumTypes | Array<EnumTypes>) {
    super();
    this.values = new Set(Array.isArray(values) ? values : [values]);
  }

  toJSON(): object {
    return { enum: Array.from(this.values) };
  }
}