From 307a4d0e82bd8a541c90afa805608c6d7351eaad Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Tue, 25 Jun 2024 11:36:47 +0100
Subject: [PATCH 1/2] fix: Skip wrapping CJS modules which result in invalid
 indenifiers

---
 hook.js                             | 26 ++++++++++----------------
 package.json                        |  3 ++-
 test/fixtures/invalid-identifier.js |  1 +
 test/hook/invalid-identifier.mjs    |  4 ++++
 4 files changed, 17 insertions(+), 17 deletions(-)
 create mode 100644 test/fixtures/invalid-identifier.js
 create mode 100644 test/hook/invalid-identifier.mjs

diff --git a/hook.js b/hook.js
index 8e534e0..62d1868 100644
--- a/hook.js
+++ b/hook.js
@@ -3,6 +3,7 @@
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
 const { URL } = require('url')
+const { isIdentifierName } = require('@babel/helper-validator-identifier')
 const specifiers = new Map()
 const isWin = process.platform === 'win32'
 
@@ -133,6 +134,10 @@ async function processModule ({ srcUrl, context, parentGetSource, parentResolve,
   const setters = new Map()
 
   const addSetter = (name, setter, isStarExport = false) => {
+    if (!isIdentifierName(name)) {
+      throw new Error(`'${name}' is not a valid ESM identifier name`)
+    }
+
     if (setters.has(name)) {
       if (isStarExport) {
         // If there's already a matching star export, delete it
@@ -261,7 +266,8 @@ function createHook (meta) {
     }
   }
 
-  async function getSource (url, context, parentGetSource) {
+  // For Node.js 16.12.0 and higher.
+  async function load (url, context, parentGetSource) {
     if (hasIitm(url)) {
       const realUrl = deleteIitm(url)
 
@@ -273,6 +279,8 @@ function createHook (meta) {
           parentResolve: cachedResolve
         })
         return {
+          shortCircuit: true,
+          format: 'module',
           source: `
 import { register } from '${iitmURL}'
 import * as namespace from ${JSON.stringify(realUrl)}
@@ -313,27 +321,13 @@ register(${JSON.stringify(realUrl)}, _, set, ${JSON.stringify(specifiers.get(rea
     return parentGetSource(url, context, parentGetSource)
   }
 
-  // For Node.js 16.12.0 and higher.
-  async function load (url, context, parentLoad) {
-    if (hasIitm(url)) {
-      const { source } = await getSource(url, context, parentLoad)
-      return {
-        source,
-        shortCircuit: true,
-        format: 'module'
-      }
-    }
-
-    return parentLoad(url, context, parentLoad)
-  }
-
   if (NODE_MAJOR >= 17 || (NODE_MAJOR === 16 && NODE_MINOR >= 12)) {
     return { load, resolve }
   } else {
     return {
       load,
       resolve,
-      getSource,
+      getSource: load,
       getFormat (url, context, parentGetFormat) {
         if (hasIitm(url)) {
           return {
diff --git a/package.json b/package.json
index d9c2c34..0e03ef8 100644
--- a/package.json
+++ b/package.json
@@ -56,6 +56,7 @@
     "acorn": "^8.8.2",
     "acorn-import-attributes": "^1.9.5",
     "cjs-module-lexer": "^1.2.2",
-    "module-details-from-path": "^1.0.3"
+    "module-details-from-path": "^1.0.3",
+    "@babel/helper-validator-identifier": "^7.24.7"
   }
 }
diff --git a/test/fixtures/invalid-identifier.js b/test/fixtures/invalid-identifier.js
new file mode 100644
index 0000000..c604f80
--- /dev/null
+++ b/test/fixtures/invalid-identifier.js
@@ -0,0 +1 @@
+exports['one.two'] = () => console.log('b')
diff --git a/test/hook/invalid-identifier.mjs b/test/hook/invalid-identifier.mjs
new file mode 100644
index 0000000..6f4acf0
--- /dev/null
+++ b/test/hook/invalid-identifier.mjs
@@ -0,0 +1,4 @@
+import * as lib from '../fixtures/invalid-identifier.js'
+import { strictEqual } from 'assert'
+
+strictEqual(typeof lib['one.two'], 'function')

From f20179c6716a50106967a43c94be21d3f7822c61 Mon Sep 17 00:00:00 2001
From: Tim Fish <tim@timfish.uk>
Date: Tue, 25 Jun 2024 12:58:06 +0100
Subject: [PATCH 2/2] change error message

---
 hook.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hook.js b/hook.js
index 62d1868..eaac130 100644
--- a/hook.js
+++ b/hook.js
@@ -135,7 +135,7 @@ async function processModule ({ srcUrl, context, parentGetSource, parentResolve,
 
   const addSetter = (name, setter, isStarExport = false) => {
     if (!isIdentifierName(name)) {
-      throw new Error(`'${name}' is not a valid ESM identifier name`)
+      throw new Error(`'${name}' export is not a valid identifier name`)
     }
 
     if (setters.has(name)) {