Convert this library to ES Modules

.eslintrc

@@ -16,9 +16,8 @@
         ]
       }
     ],
-    "import/extensions": ["error", "never", {
-      "json": "always",
-    }],
+    // Disabled due to https://github.com/import-js/eslint-plugin-import/issues/2104
+    "import/extensions": [0, "never"],
     // This rule conflicts with our convention.
     "jest/valid-describe": "off",
     // This is not needed for this project.
@@ -32,20 +31,13 @@
     "@typescript-eslint/explicit-function-return-type": "off",
     "@typescript-eslint/no-explicit-any": "error",
     "@typescript-eslint/explicit-member-accessibility": "off",
-    "import/no-unresolved": ["error", {
-      ignore: ['estree'],
-    }],
+    // This is sad but we have to disable this rule to allow TS to generate
+    // correct a ESM package.
+    "import/no-unresolved": "off",
     // This rule is annoying and does not add any value.
     "@typescript-eslint/camelcase": "off",
     "@typescript-eslint/ban-ts-comment": ["error", {
       "ts-expect-error": "allow-with-description",
-    }],
-  },
-  "settings": {
-    "import/resolver": {
-      "node": {
-        "extensions": [".js", ".ts"]
-      }
-    }
+    }]
   }
 }

jest.config.js

@@ -1,5 +1,9 @@
-module.exports = {
+export default {
   preset: 'ts-jest',
+  moduleNameMapper: {
+    // Replace imports ending with `.js` with imports without extensions.
+    '^(\\.{1,2}/.*)\\.js$': '$1',
+  },
   testEnvironment: 'node',
   testPathIgnorePatterns: ['<rootDir>/dist/', '<rootDir>/node_modules/'],
 };

package.json

@@ -2,10 +2,16 @@
   "name": "addons-scanner-utils",
   "version": "9.0.0",
   "description": "Various addons related helpers to build CLIs.",
-  "main": "dist/index.js",
-  "types": "dist/index.d.ts",
+  "type": "module",
+  "main": "./dist/index.js",
+  "types": "./dist/index.d.ts",
+  "exports": {
+    ".": "./dist/index.js",
+    "./io": "./dist/io/index.js",
+    "./test-helpers": "./dist/test-helpers.js"
+  },
   "files": [
-    "dist/**/*"
+    "dist/**"
   ],
   "author": "Mozilla Add-ons Team",
   "license": "MPL-2.0",
@@ -42,12 +48,12 @@
     "@types/express": "4.17.17",
     "@types/jest": "^29.0.0",
     "@types/node": "^18.0.0",
-    "@types/node-fetch": "^2.6.2",
+    "@types/node-fetch": "^2.6.3",
     "@types/safe-compare": "^1.1.0",
     "@types/sinon": "^10.0.0",
     "@types/supertest": "^2.0.8",
-    "@typescript-eslint/eslint-plugin": "^5.0.0",
-    "@typescript-eslint/parser": "^5.0.0",
+    "@typescript-eslint/eslint-plugin": "^5.58.0",
+    "@typescript-eslint/parser": "^5.58.0",
     "body-parser": "1.20.2",
     "eslint": "^8.1.0",
     "eslint-config-amo": "^5.0.0",

src/@types/safe-compare/index.d.ts

@@ -0,0 +1,7 @@
+// The `@types/safe-compare` package does not declare a module and that breaks
+// the type checker...
+declare module 'safe-compare' {
+  function safeCompare(a: string, b: string): boolean;
+
+  export default safeCompare;
+}

src/const.spec.ts → src/constants.spec.ts

@@ -1,6 +1,6 @@
-import { ECMA_VERSION } from './const';
+import { ECMA_VERSION } from './constants.js';
 
-describe(__filename, () => {
+describe('constants', () => {
   it('exports an ECMA_VERSION constant', () => {
     expect(ECMA_VERSION).toEqual(13);
   });

src/functions.spec.ts

@@ -11,11 +11,11 @@ import {
   RequestWithFiles,
   createApiError,
   createExpressApp,
-} from './functions';
+} from './functions.js';
 
 jest.mock('node-fetch');
 
-describe(__filename, () => {
+describe('functions', () => {
   describe('createApiError', () => {
     it('returns an API error with a message', () => {
       const message = 'oops, error';

src/index.ts

@@ -1,5 +1,5 @@
-export * from './const';
-export * from './functions';
-export * from './io';
-export * from './stdio';
-export * from './errors';
+export * from './constants.js';
+export * from './functions.js';
+export * from './io/index.js';
+export * from './stdio.js';
+export * from './errors.js';

src/io/base.spec.ts

@@ -1,8 +1,8 @@
-import { IOBase } from './base';
-import { FLAGGED_FILE_MAGIC_NUMBERS_LENGTH } from './const';
-import { createFakeStderr } from '../test-helpers';
+import { IOBase } from './base.js';
+import { FLAGGED_FILE_MAGIC_NUMBERS_LENGTH } from './constants.js';
+import { createFakeStderr } from '../test-helpers.js';
 
-describe(__filename, () => {
+describe('io/base', () => {
   const createIOBase = ({
     filePath = 'foo/bar/',
     stderr = createFakeStderr(),

src/io/base.ts

@@ -2,8 +2,11 @@ import { Readable } from 'stream';
 
 import { oneLine } from 'common-tags';
 
-import { FLAGGED_FILE_MAGIC_NUMBERS_LENGTH, MAX_FILE_SIZE_MB } from './const';
-import { Stderr } from '../stdio';
+import {
+  FLAGGED_FILE_MAGIC_NUMBERS_LENGTH,
+  MAX_FILE_SIZE_MB,
+} from './constants.js';
+import { Stderr } from '../stdio.js';
 
 type ScanFileFunction = (_path: string, isDirectory: boolean) => boolean;
 

src/io/crx.spec.ts

@@ -3,12 +3,12 @@ import defaultFs from 'fs';
 import yauzl, { Entry, ZipFile } from 'yauzl';
 import realSinon, { SinonSandbox, SinonStub } from 'sinon';
 
-import { defaultParseCRX, Crx } from './crx';
-import { Files } from './xpi';
-import { DEFLATE_COMPRESSION, NO_COMPRESSION } from './const';
-import { createFakeStderr, createFakeZipFile } from '../test-helpers';
+import { defaultParseCRX, Crx } from './crx.js';
+import { Files } from './xpi.js';
+import { DEFLATE_COMPRESSION, NO_COMPRESSION } from './constants.js';
+import { createFakeStderr, createFakeZipFile } from '../test-helpers.js';
 
-describe(__filename, () => {
+describe('io/crx', () => {
   const defaultData = {
     compressionMethod: DEFLATE_COMPRESSION,
   };

src/io/crx.ts

@@ -2,8 +2,8 @@ import defaultFs from 'fs';
 
 import yauzl, { ZipFile } from 'yauzl';
 
-import { IOBaseConstructorParams } from './base';
-import { Xpi } from './xpi';
+import { IOBaseConstructorParams } from './base.js';
+import { Xpi } from './xpi.js';
 
 export function defaultParseCRX(buf: Buffer): Buffer {
   if (buf.readUInt32BE(0) !== 0x43723234) {

src/io/directory.spec.ts

@@ -1,10 +1,10 @@
 import { Readable } from 'stream';
 import { EventEmitter } from 'events';
 
-import { Directory } from './directory';
-import { createFakeStderr, readStringFromStream } from '../test-helpers';
+import { Directory } from './directory.js';
+import { createFakeStderr, readStringFromStream } from '../test-helpers.js';
 
-describe(__filename, () => {
+describe('io/directory', () => {
   const fakeFile = {
     size: 123,
   };

src/io/directory.ts

@@ -6,8 +6,8 @@ import FirstChunkStream from 'first-chunk-stream';
 import stripBomStream from 'strip-bom-stream';
 import { oneLine } from 'common-tags';
 
-import { IOBase, IOBaseConstructorParams } from './base';
-import { walkPromise } from './utils';
+import { IOBase, IOBaseConstructorParams } from './base.js';
+import { walkPromise } from './utils.js';
 
 type Files = { [filename: string]: { size: number } };
 

src/io/index.ts

@@ -1,5 +1,5 @@
-export * from './const';
-export * from './crx';
-export * from './directory';
-export * from './utils';
-export * from './xpi';
+export * from './constants.js';
+export * from './crx.js';
+export * from './directory.js';
+export * from './utils.js';
+export * from './xpi.js';

src/io/utils.spec.ts

@@ -1,7 +1,7 @@
-import { WalkPromiseOptions, checkFileExists, walkPromise } from './utils';
-import { createFakeFsStats, createFakeStderr } from '../test-helpers';
+import { WalkPromiseOptions, checkFileExists, walkPromise } from './utils.js';
+import { createFakeFsStats, createFakeStderr } from '../test-helpers.js';
 
-describe(__filename, () => {
+describe('io/utils', () => {
   describe('walkPromise()', () => {
     const _walkPromise = ({
       path = 'src/tests/fixtures/io/',

src/io/utils.ts

@@ -4,7 +4,7 @@ import { promisify } from 'util';
 
 import upath from 'upath';
 
-import { Stderr } from '../stdio';
+import { Stderr } from '../stdio.js';
 
 export const lstat = promisify(fs.lstat);
 export const readFile = promisify(fs.readFile);

src/io/xpi.spec.ts

@@ -5,16 +5,16 @@ import { EventEmitter } from 'events';
 import yauzl, { Entry, ZipFile } from 'yauzl';
 import realSinon, { SinonSandbox, SinonStub } from 'sinon';
 
-import { DuplicateZipEntryError, InvalidZipFileError } from '../errors';
-import { Xpi, Files } from './xpi';
-import { DEFLATE_COMPRESSION, NO_COMPRESSION } from './const';
+import { DuplicateZipEntryError, InvalidZipFileError } from '../errors.js';
+import { Xpi, Files } from './xpi.js';
+import { DEFLATE_COMPRESSION, NO_COMPRESSION } from './constants.js';
 import {
   createFakeStderr,
   createFakeZipFile,
   readStringFromStream,
-} from '../test-helpers';
+} from '../test-helpers.js';
 
-describe(__filename, () => {
+describe('io/xpi', () => {
   const defaultData = {
     compressionMethod: DEFLATE_COMPRESSION,
   };

src/io/xpi.ts

@@ -5,8 +5,8 @@ import FirstChunkStream from 'first-chunk-stream';
 import stripBomStream from 'strip-bom-stream';
 import { oneLine } from 'common-tags';
 
-import { IOBaseConstructorParams, IOBase } from './base';
-import { InvalidZipFileError, DuplicateZipEntryError } from '../errors';
+import { IOBaseConstructorParams, IOBase } from './base.js';
+import { InvalidZipFileError, DuplicateZipEntryError } from '../errors.js';
 
 export type Files = { [filename: string]: Entry };
 

src/stdio.spec.ts

@@ -3,9 +3,9 @@ import {
   createConsoleStdout,
   createInMemoryStderr,
   createInMemoryStdout,
-} from './stdio';
+} from './stdio.js';
 
-describe(__filename, () => {
+describe('stdio', () => {
   const createFakeConsole = () => {
     return {
       ...console,

src/test-helpers.ts

@@ -2,7 +2,7 @@ import { Readable } from 'stream';
 
 import { ZipFile, RandomAccessReader } from 'yauzl';
 
-import { Stderr, Stdout } from './stdio';
+import { Stderr, Stdout } from './stdio.js';
 
 export const createFakeStdout = (): Stdout => {
   return {

tsconfig.json

@@ -1,14 +1,14 @@
 {
   "compilerOptions": {
-    "allowSyntheticDefaultImports": true,
+    "outDir": "dist",
     "declaration": true,
     "esModuleInterop": true,
     "forceConsistentCasingInFileNames": true,
-    "module": "commonjs",
-    "moduleResolution": "node",
+    "module": "nodenext",
+    "moduleResolution": "nodenext",
     "resolveJsonModule": true,
     "strict": true,
-    "target": "es2015",
+    "target": "es2022",
     "typeRoots" : ["./node_modules/@types", "./src/@types"]
   }
 }