chore: add types to the debugger logger (#6889)

Author: watson

packages/dd-trace/src/debugger/devtools_client/log.js

@@ -1,10 +1,15 @@
 'use strict'
 
+/** @typedef {'error'|'warn'|'info'|'debug'} Level */
+/** @typedef {(...args: unknown[]) => void} LogFn */
+/** @typedef {Record<Level, LogFn>} Logger */
+
 const { workerData } = require('node:worker_threads')
 
 // For testing purposes, we allow `workerData` to be undefined and fallback to a default config
-const { config: { debug, logLevel }, logPort } = workerData ?? { config: { debug: false } }
+const { config: { debug = false, logLevel } = {}, logPort } = workerData ?? {}
 
+/** @type {Level[]} */
 const LEVELS = ['error', 'warn', 'info', 'debug']
 const on = (level, ...args) => {
   if (typeof args[0] === 'function') {
@@ -14,6 +19,12 @@ const on = (level, ...args) => {
 }
 const off = () => {}
 
-for (const level of LEVELS) {
-  module.exports[level] = debug && LEVELS.indexOf(logLevel) >= LEVELS.indexOf(level) ? on.bind(null, level) : off
-}
+const threshold = LEVELS.indexOf(logLevel)
+
+/** @type {Logger} */
+module.exports = Object.fromEntries(
+  LEVELS.map(level => [
+    level,
+    debug && threshold >= LEVELS.indexOf(level) ? on.bind(null, level) : off
+  ])
+)