JSDoc: restricting key names and allowable values in VSCode

JSDoc Object Property Name Restrictions and Value Restrictions.js

/*
 * Defining restrictions on allowable property names is easy in typescript; in JSDoc, not so much.
 *
 * Here's what I found works with javascript/JSDoc, so far as working fully with IntelliSense in VSCode.
 * The secret sauce is:
 *
 * \@typedef {{[S in LogLevelName]: LogFunction}} LoggerObject
 */

/**
 * Valid log level names as a string enum
 * @typedef {"error" | "warn" |  "success" |  "successv" |  "info" |  "help" |  "verbose" |  "debug" |  "silly"} LogLevelName
 */

/**
 * Valid log level numeric values
 * @typedef {0 | 1 | 2 | 4 | 5 | 6} LogLevelNumeric
 */

/**
 * Map of log level names to numeric values
 * @typedef {{[S in LogLevelName]: LogLevelNumeric}} LogLevelMap
 */

/** @type {LogLevelMap} */
const levels = {
  error: 0,
  warn: 1,
  success: 2,
  successv: 2,
  info: 2,
  help: 2,
  verbose: 4,
  debug: 5,
  silly: 6,
};

/**
 * Generic form of a logging function
 * @typedef {function(string, ...any): void} LogFunction
 */

/**
 * A type of object that provides log functions for each log level
 * @typedef {{[S in LogLevelName]: LogFunction}} LoggerObject
 */

/**
 * A logger object type that extends LoggerObject
 * @typedef {Object} Logger
 * @property {LogLevelName} level
 * @property {function(LogLevelName): void} setLevel - set logger level
 * @property {function(string): void} setName - set logger name
 * @property {function(string): void} setVersion - set logger version
 */

/** @type {Logger & LoggerObject} */
const logger = {
  // track level
  level: "debug",
  // errors
  error: (msg, ...otherArgs) => console.error("error", msg, ...otherArgs),
  // .... and so on ...
};

To see how VSCode / Codesandbox.io handles the Intellisense, check out this codesandbox :

Here are some screenshots: