add log function for debugging loader

Author: bumblehead

CHANGELOG.md

@@ -1,5 +1,7 @@
 # changelog
 
+ * 2.6.8 _tbd_
+   * add log utility for debugging loader
  * 2.6.7 _Jul.16.2024_
    * [add swc tests and remove swc caution from README](https://github.com/iambumblehead/esmock/pull/309) thanks @Brooooooklyn
    * [unpin node 22.1 at test CI](https://github.com/iambumblehead/esmock/pull/309) and use latest 22.x

src/esmockLoader.js

@@ -1,4 +1,4 @@
-import fs from 'node:fs/promises'
+import fs from 'node:fs'
 import module from 'node:module'
 import process from 'process'
 import esmockErr from './esmockErr.js'
@@ -33,6 +33,10 @@ const moduleIdReCreate = (moduleid, treeid) => new RegExp(
 const mockKeys = global.mockKeys = (global.mockKeys || {})
 const mockKeysSource = global.mockKeysSource = (global.mockKeysSource || {})
 
+// use fs when logging from hooks, console.log async unpredictable
+const log = (...args) => (
+  fs.writeSync(1, JSON.stringify(args, null, '  ').slice(2, -1)))
+
 // node v20.0-v20.6
 const globalPreload = !module.register && (({ port }) => (
   port.addEventListener('message', ev => (
@@ -170,7 +174,7 @@ const load = async (url, context, nextLoad) => {
       const sourceIsNullLike = (
         nextLoadRes.source === null || nextLoadRes.source === undefined)
       const source = sourceIsNullLike
-        ? String(await fs.readFile(new URL(url)))
+        ? String(fs.readFileSync(new URL(url)))
         : String(nextLoadRes.source)
       const hbang = (source.match(hashbangRe) || [])[0] || ''
       const sourcesafe = hbang ? source.replace(hashbangRe, '') : source