add linting

.eslintrc.js

@@ -0,0 +1,30 @@
+module.exports = {
+  env: {
+    browser: true,
+    commonjs: true,
+    es2021: true
+  },
+  extends: [
+    'eslint:recommended',
+    'standard'
+  ],
+  overrides: [
+    {
+      env: {
+        node: true
+      },
+      files: [
+        '.eslintrc.{js,cjs}'
+      ],
+      parserOptions: {
+        sourceType: 'script'
+      }
+    }
+  ],
+  parserOptions: {
+    ecmaVersion: 'latest'
+  },
+  rules: {
+    'no-unused-vars': ['error', { varsIgnorePattern: '^_$' }]
+  }
+}

hook.js

@@ -4,7 +4,7 @@
 
 const { randomBytes } = require('crypto')
 const specifiers = new Map()
-const isWin = process.platform === "win32"
+const isWin = process.platform === 'win32'
 
 // FIXME: Typescript extensions are added temporarily until we find a better
 // way of supporting arbitrary extensions
@@ -16,7 +16,7 @@ const NODE_MINOR = Number(NODE_VERSION[1])
 let entrypoint
 
 let getExports
-if (NODE_MAJOR >= 20 || (NODE_MAJOR == 18 && NODE_MINOR >= 19)) {
+if (NODE_MAJOR >= 20 || (NODE_MAJOR === 18 && NODE_MINOR >= 19)) {
   getExports = require('./lib/get-exports.js')
 } else {
   getExports = (url) => import(url).then(Object.keys)
@@ -56,10 +56,6 @@ function deleteIitm (url) {
   return resultUrl
 }
 
-function isNode16AndBiggerOrEqualsThan16_17_0() {
-  return NODE_MAJOR === 16 && NODE_MINOR >= 17
-}
-
 function isFileProtocol (urlObj) {
   return urlObj.protocol === 'file:'
 }
@@ -68,11 +64,11 @@ function isNodeProtocol (urlObj) {
   return urlObj.protocol === 'node:'
 }
 
-function needsToAddFileProtocol(urlObj) {
+function needsToAddFileProtocol (urlObj) {
   if (NODE_MAJOR === 17) {
     return !isFileProtocol(urlObj)
   }
-  if (isNode16AndBiggerOrEqualsThan16_17_0()) {
+  if (NODE_MAJOR === 16 && NODE_MINOR >= 17) {
     return !isFileProtocol(urlObj) && !isNodeProtocol(urlObj)
   }
   return !isFileProtocol(urlObj) && NODE_MAJOR < 18
@@ -87,7 +83,7 @@ function needsToAddFileProtocol(urlObj) {
  * @param {string} line
  * @returns {boolean}
  */
-function isStarExportLine(line) {
+function isStarExportLine (line) {
   return /^\* from /.test(line)
 }
 
@@ -115,7 +111,7 @@ function isStarExportLine(line) {
  * module.
  * @returns {Promise<ProcessedModule>}
  */
-async function processModule({ srcUrl, context, parentGetSource }) {
+async function processModule ({ srcUrl, context, parentGetSource }) {
   const exportNames = await getExports(srcUrl, context, parentGetSource)
   const imports = [`import * as namespace from ${JSON.stringify(srcUrl)}`]
   const namespaces = ['namespace']
@@ -180,7 +176,6 @@ function createHook (meta) {
       return url
     }
 
-
     specifiers.set(url.url, specifier)
 
     return {
@@ -195,9 +190,9 @@ function createHook (meta) {
     if (hasIitm(url)) {
       const realUrl = deleteIitm(url)
       const { imports, namespaces, setters } = await processModule({
-          srcUrl: realUrl,
-          context,
-          parentGetSource
+        srcUrl: realUrl,
+        context,
+        parentGetSource
       })
 
       return {

index.js

@@ -12,26 +12,26 @@ const {
   toHook
 } = require('./lib/register')
 
-function addHook(hook) {
+function addHook (hook) {
   importHooks.push(hook)
   toHook.forEach(([name, namespace]) => hook(name, namespace))
 }
 
-function removeHook(hook) {
+function removeHook (hook) {
   const index = importHooks.indexOf(hook)
   if (index > -1) {
     importHooks.splice(index, 1)
   }
 }
 
-function callHookFn(hookFn, namespace, name, baseDir) {
+function callHookFn (hookFn, namespace, name, baseDir) {
   const newDefault = hookFn(namespace, name, baseDir)
   if (newDefault && newDefault !== namespace) {
     namespace.default = newDefault
   }
 }
 
-function Hook(modules, options, hookFn) {
+function Hook (modules, options, hookFn) {
   if ((this instanceof Hook) === false) return new Hook(modules, options, hookFn)
   if (typeof modules === 'function') {
     hookFn = modules

lib/get-esm-exports.js

@@ -1,7 +1,7 @@
 'use strict'
 
 const { Parser } = require('acorn')
-const { importAssertions } = require('acorn-import-assertions');
+const { importAssertions } = require('acorn-import-assertions')
 
 const acornOpts = {
   ecmaVersion: 'latest',

lib/get-exports.js

@@ -5,7 +5,7 @@ const { parse: getCjsExports } = require('cjs-module-lexer')
 const fs = require('fs')
 const { fileURLToPath } = require('url')
 
-function addDefault(arr) {
+function addDefault (arr) {
   return Array.from(new Set(['default', ...arr]))
 }
 

lib/register.js

@@ -2,18 +2,17 @@
 //
 // This product includes software developed at Datadog (https://www.datadoghq.com/). Copyright 2021 Datadog, Inc.
 
-
 const importHooks = [] // TODO should this be a Set?
 const setters = new WeakMap()
 const specifiers = new Map()
 const toHook = []
 
 const proxyHandler = {
-  set(target, name, value) {
+  set (target, name, value) {
     return setters.get(target)[name](value)
   },
 
-  defineProperty(target, property, descriptor) {
+  defineProperty (target, property, descriptor) {
     if ((!('value' in descriptor))) {
       throw new Error('Getters/setters are not supported for exports property descriptors.')
     }
@@ -22,7 +21,7 @@ const proxyHandler = {
   }
 }
 
-function register(name, namespace, set, specifier) {
+function register (name, namespace, set, specifier) {
   specifiers.set(name, specifier)
   setters.set(namespace, set)
   const proxy = new Proxy(namespace, proxyHandler)

package.json

@@ -4,6 +4,8 @@
   "description": "Intercept imports in Node.js",
   "main": "index.js",
   "scripts": {
+    "lint": "eslint .",
+    "pretest": "npm run lint",
     "test": "c8 --reporter lcov --check-coverage --lines 70 imhotap --runner 'node test/runtest' --files test/{hook,low-level,other,get-esm-exports}/*",
     "test:ts": "c8 --reporter lcov imhotap --runner 'node test/runtest' --files test/typescript/*.test.mts",
     "coverage": "c8 --reporter html imhotap --runner 'node test/runtest' --files test/{hook,low-level,other,get-esm-exports}/* && echo '\nNow open coverage/index.html\n'"
@@ -29,6 +31,11 @@
   "devDependencies": {
     "@types/node": "^18.0.6",
     "c8": "^7.8.0",
+    "eslint": "^8.55.0",
+    "eslint-config-standard": "^17.1.0",
+    "eslint-plugin-import": "^2.29.0",
+    "eslint-plugin-n": "^16.4.0",
+    "eslint-plugin-promise": "^6.1.1",
     "imhotap": "^2.1.0",
     "ts-node": "^10.9.1",
     "typescript": "^4.7.4"

test/fixtures/something.js

@@ -4,7 +4,7 @@
 
 'use strict'
 
-module.exports = function bar() {
+module.exports = function bar () {
   return 42
 }
 module.exports.foo = 42

test/hook/dynamic-import-default.js

@@ -8,13 +8,13 @@ const { strictEqual } = require('assert')
 Hook((exports, name) => {
   if (name.match(/something.js/)) {
     const orig = exports.default
-    exports.default = function bar() {
+    exports.default = function bar () {
       return orig() + 15
     }
   }
   if (name.match(/something.mjs/)) {
     const orig = exports.default
-    return function bar() {
+    return function bar () {
       return orig() + 15
     }
   }

test/low-level/dynamic-import-default.js

@@ -8,7 +8,7 @@ const { strictEqual } = require('assert')
 addHook((name, exports) => {
   if (name.match(/something\.m?js/)) {
     const orig = exports.default
-    exports.default = function bar() {
+    exports.default = function bar () {
       return orig() + 15
     }
   }