Add eslint and jest

eslint.config.js

@@ -0,0 +1,11 @@
+import globals from "globals";
+import pluginJs from "@eslint/js";
+
+export default [
+  {
+    languageOptions: {
+      globals: globals.node
+    }
+  },
+  pluginJs.configs.recommended,
+];

package.json

@@ -4,7 +4,11 @@
   "description": "Scribd Document Downloader",
   "main": "index.js",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "start": "node run.js",
+    "test": "node --experimental-vm-modules node_modules/jest/bin/jest.js",
+    "test:watch": "node --experimental-vm-modules node_modules/jest/bin/jest.js --watch",
+    "test:cov": "node --experimental-vm-modules node_modules/jest/bin/jest.js --coverage",
+    "lint": "eslint --fix \"{src,apps,libs}/**/*.js\""
   },
   "keywords": [],
   "author": {
@@ -20,5 +24,14 @@
     "sharp": "^0.33.3"
   },
   "type": "module",
-  "types": "module"
+  "types": "module",
+  "devDependencies": {
+    "@eslint/js": "^9.1.1",
+    "eslint": "^9.1.1",
+    "globals": "^15.0.0",
+    "jest": "^29.7.0"
+  },
+  "jest": {
+    "transform": {}
+  }
 }

run.js

@@ -3,5 +3,5 @@ import { app } from './src/App.js'
 if (process.argv.length == 3) {
     await app.execute(process.argv[2])
 } else {
-    console.error(`Usage: node run.js [URL]`)
+    console.error(`Usage: npm start [URL]`)
 }

src/service/ScribdDownloader.js

@@ -1,5 +1,4 @@
 import cliProgress from "cli-progress"
-import path from 'path'
 import { puppeteerSg } from "../utils/request/PuppeteerSg.js";
 import { pdfGenerator } from "../utils/io/PdfGenerator.js";
 import { configLoader } from "../utils/io/ConfigLoader.js";
@@ -60,7 +59,7 @@ class ScribdDownloader {
             const bar = new cliProgress.SingleBar({}, cliProgress.Presets.shades_classic);
             bar.start(doc_pages.length, 0);
             for (let i = 0; i < doc_pages.length; i++) {
-                await page.evaluate((i) => {
+                await page.evaluate((i) => { // eslint-disable-next-line
                     document.getElementById(`outer_page_${(i + 1)}`).scrollIntoView()
                 }, i)
                 

src/utils/io/ConfigLoader.js

@@ -20,7 +20,11 @@ class ConfigLoader {
      * @returns {Promise<string>}
      */
     load(section, key) {
-        return config[section][key]
+        if (Object.keys(config[section]).includes(key)) {
+            return config[section][key]
+        } else {
+            throw new TypeError(`Unknown key: ${key}`)
+        }
     }
 }
 

src/utils/io/DirectoryIo.js

@@ -1,5 +1,4 @@
-import fs, { Dir } from 'fs'
-import path from 'path'
+import fs from 'fs'
 
 class DirectoryIo {
     constructor() {

src/utils/io/PdfGenerator.js

@@ -1,6 +1,7 @@
 import PDFDocument from 'pdfkit'
 import fs from 'fs'
-import sharp from "sharp"
+
+// eslint-disable-next-line
 import { Image } from '../../object/Image.js'
 
 class PdfGenerator {

src/utils/request/PuppeteerSg.js

@@ -41,7 +41,7 @@ class PuppeteerSg {
    * Close the browser
    */
   async close() {
-    if (!!this.browser) {
+    if (this.browser) {
       await this.browser.close();
       this.browser = null;
     }

test/ConfigLoader.test.js

@@ -0,0 +1,18 @@
+import { configLoader } from "../src/utils/io/ConfigLoader.js";
+
+
+describe("load", () => {
+    test("return 'output' if load DIRECTORY.output", () => {
+        expect(configLoader.load("DIRECTORY", "output")).toBe("output");
+    })
+    test("throw an error if load unknown section", () => {
+        expect(() => {
+            configLoader.load("FOO", "output")
+        }).toThrow(TypeError)
+    })
+    test("throw an error if load unknown key", () => {
+        expect(() => {
+            configLoader.load("DIRECTORY", "FOO")
+        }).toThrow(TypeError)
+    })
+})