switch to CJS for index, and remove enabled

CJS allows us to add hooks from CJS files synchronously.

"enabled" is just too hard to properly track when accounting for CJS.

hook.mjs

@@ -30,7 +30,7 @@ export function getFormat (url, context, parentGetFormat) {
   return parentGetFormat(url, context, parentGetFormat)
 }
 
-const iitmURL = new URL('index.mjs', import.meta.url).toString()
+const iitmURL = new URL('index.js', import.meta.url).toString()
 export async function getSource (url, context, parentGetSource) {
   if (url.startsWith('iitm:')) {
     const realName = url.replace('iitm:', '')

index.mjs → index.js

@@ -14,26 +14,19 @@ const proxyHandler = {
   }
 }
 
-let isEnabled = false
-
-export function enabled() {
-  return isEnabled
-}
-
-export function _register(name, namespace, set) {
-  isEnabled = true
+exports._register =  function _register(name, namespace, set) {
   setters.set(namespace, set)
   const proxy = new Proxy(namespace, proxyHandler)
   importHooks.forEach(hook => hook(name, proxy))
   toHook.push([name, proxy])
 }
 
-export function addHook(hook) {
+exports.addHook = function addHook(hook) {
   importHooks.push(hook)
   toHook.forEach(([name, namespace]) => hook(name, namespace))
 }
 
-export function removeHook(hook) {
+exports.removeHook = function removeHook(hook) {
   const index = importHooks.indexOf(hook)
   if (index > -1) {
     importHooks.splice(index, 1)

package.json

@@ -4,7 +4,7 @@
   "description": "Intercept imports in Node.js",
   "main": "index.mjs",
   "scripts": {
-    "test": "c8 --check-coverage --lines 100 imhotap --runner test/runtest --files test/*.mjs"
+    "test": "c8 --check-coverage --lines 100 imhotap --runner test/runtest --files test/*.*js"
   },
   "repository": {
     "type": "git",

test/dynamic-import-default.js

@@ -0,0 +1,23 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2.0 License.
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
+
+const { addHook } = require('../index.js')
+const { strictEqual } = require('assert')
+
+addHook((name, exports) => {
+  if (name.match(/something\.m?js/)) {
+    const orig = exports.default
+    exports.default = function bar() {
+      return orig() + 15
+    }
+  }
+})
+
+;(async () => {
+  const { default: barMjs } = await import('./fixtures/something.mjs')
+  const { default: barJs } = await import('./fixtures/something.js')
+
+  strictEqual(barMjs(), 57)
+  strictEqual(barJs(), 57)
+})()

test/dynamic-import-default.mjs

@@ -2,10 +2,8 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-import { addHook, enabled } from '../index.mjs'
-import { strictEqual, ok } from 'assert'
-
-ok(enabled())
+import { addHook } from '../index.js'
+import { strictEqual } from 'assert'
 
 addHook((name, exports) => {
   if (name.match(/something\.m?js/)) {

test/dynamic-import.js

@@ -0,0 +1,25 @@
+// Unless explicitly stated otherwise all files in this repository are licensed under the Apache 2.0 License.
+//
+// This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
+
+const { addHook } = require('../index.js')
+const { strictEqual } = require('assert')
+
+addHook((name, exports) => {
+  if (name.match(/something\.m?js/)) {
+    exports.foo += 15
+  }
+  if (name.match('os')) {
+    exports.freemem = () => 47
+  }
+})
+
+;(async () => {
+  const { foo: fooMjs } = await import('./fixtures/something.mjs')
+  const { foo: fooJs } = await import('./fixtures/something.js')
+  const { freemem } = await import('os')
+
+  strictEqual(fooMjs, 57)
+  strictEqual(fooJs, 57)
+  strictEqual(freemem(), 47)
+})()

test/dynamic-import.mjs

@@ -2,10 +2,8 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-import { addHook, enabled } from '../index.mjs'
-import { strictEqual, ok } from 'assert'
-
-ok(enabled())
+import { addHook } from '../index.js'
+import { strictEqual } from 'assert'
 
 addHook((name, exports) => {
   if (name.match(/something\.m?js/)) {

test/remove.mjs

@@ -2,11 +2,9 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-import { addHook, removeHook, enabled } from '../index.mjs'
+import { addHook, removeHook } from '../index.js'
 import { strictEqual, ok } from 'assert'
 
-ok(enabled())
-
 const hook = (name, exports) => {
   if (name.match(/something\.m?js/)) {
     exports.foo += 15

test/static-import-default.mjs

@@ -2,12 +2,10 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-import { addHook, enabled } from '../index.mjs'
+import { addHook } from '../index.js'
 import barMjs from './fixtures/something.mjs'
 import barJs from './fixtures/something.js'
-import { strictEqual, ok } from 'assert'
-
-ok(enabled())
+import { strictEqual } from 'assert'
 
 addHook((name, exports) => {
   if (name.match(/something\.m?js/)) {

test/static-import-disabled.mjs

@@ -2,12 +2,10 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-import { addHook, enabled } from '../index.mjs'
+import { addHook } from '../index.js'
 import { foo as fooMjs } from './fixtures/something.mjs'
 import { foo as fooJs } from './fixtures/something.js'
-import { strictEqual, fail, ok} from 'assert'
-
-ok(!enabled())
+import { strictEqual, fail } from 'assert'
 
 addHook(() => {
   fail('should not have been called at all')

test/static-import.mjs

@@ -2,13 +2,11 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-import { addHook, enabled } from '../index.mjs'
+import { addHook } from '../index.js'
 import { foo as fooMjs } from './fixtures/something.mjs'
 import { foo as fooJs } from './fixtures/something.js'
 import { freemem } from 'os'
-import { strictEqual, ok } from 'assert'
-
-ok(enabled())
+import { strictEqual } from 'assert'
 
 addHook((name, exports) => {
   if (name.match(/something\.m?js/)) {