Migrate to ESLint 10 flat config and TypeScript 6 with strict mode

.vscodeignore

@@ -7,4 +7,5 @@ src/**
 **/*.map
 .gitignore
 tsconfig.json
+eslint.config.mjs
 vsc-extension-quickstart.md

eslint.config.mjs

@@ -0,0 +1,53 @@
+import { defineConfig } from 'eslint/config';
+import tseslint from 'typescript-eslint';
+
+export default defineConfig([
+  {
+    ignores: ['out/**', 'node_modules/**', '.vscode-test/**'],
+  },
+  {
+    files: ['**/*.ts'],
+    languageOptions: {
+      parser: tseslint.parser,
+      ecmaVersion: 2019,
+      sourceType: 'module',
+    },
+    plugins: {
+      '@typescript-eslint': tseslint.plugin,
+    },
+    rules: {
+      'curly': 'error',
+      'default-case': 'error',
+      'eqeqeq': ['error', 'always', { 'null': 'ignore' }],
+      'guard-for-in': 'error',
+      'max-len': ['warn', { 'code': 140 }],
+      'no-bitwise': 'error',
+      'no-caller': 'error',
+      'no-cond-assign': 'error',
+      'no-console': ['warn', { 'allow': ['warn', 'error'] }],
+      'no-debugger': 'error',
+      'no-empty': 'error',
+      'no-eval': 'error',
+      'no-fallthrough': 'error',
+      'no-multiple-empty-lines': ['error', { 'max': 1 }],
+      'no-new-wrappers': 'error',
+      'no-redeclare': 'off',
+      'no-trailing-spaces': 'error',
+      'no-var': 'error',
+      'quotes': ['error', 'single', { 'avoidEscape': true }],
+      'radix': 'error',
+      'semi': ['error', 'always'],
+      '@typescript-eslint/no-redeclare': 'error',
+      '@typescript-eslint/no-require-imports': 'error',
+      '@typescript-eslint/no-shadow': 'error',
+      '@typescript-eslint/no-unused-expressions': 'warn',
+      '@typescript-eslint/no-use-before-define': 'error',
+    },
+  },
+  {
+    files: ['test/**/*.ts'],
+    rules: {
+      '@typescript-eslint/no-unused-expressions': 'off',
+    },
+  },
+]);

package.json

@@ -75,17 +75,17 @@
     "@types/chai": "^4.3.0",
     "@types/mocha": "^10.0.0",
     "@types/node": "^22.0.0",
+    "@types/proxyquire": "^1.3.31",
     "@types/sinon": "^17.0.0",
     "@types/vscode": "^1.32.0",
-    "@typescript-eslint/eslint-plugin": "^8.0.0",
-    "@typescript-eslint/parser": "^8.0.0",
     "@vscode/test-cli": "^0.0.15",
     "@vscode/test-electron": "^3.1.0",
     "chai": "^4.4.0",
-    "eslint": "^8.57.0",
+    "eslint": "^10.11.0",
     "proxyquire": "^2.1.3",
     "sinon": "^19.0.0",
-    "typescript": "^5.0.0"
+    "typescript": "~6.0.3",
+    "typescript-eslint": "^8.71.0"
   },
   "resolutions": {
     "serialize-javascript": "^7.0.5"

src/extension.ts

@@ -11,8 +11,11 @@ export function activate(context: vscode.ExtensionContext): void {
 
   const packwerk = new Packwerk(diag);
   const disposable = vscode.commands.registerCommand('ruby.packwerk', () => {
-    const document = vscode.window.activeTextEditor.document;
-    packwerk.execute(document);
+    const editor = vscode.window.activeTextEditor;
+    if (!editor) {
+      return;
+    }
+    packwerk.execute(editor.document);
   });
 
   context.subscriptions.push(disposable);

src/outputParser.ts

@@ -8,7 +8,7 @@ export function parseOutput(str: string): PackwerkOutput {
   } catch {
     const files = new Map<string, PackwerkFile>();
 
-    let arr: RegExpExecArray;
+    let arr: RegExpExecArray | null;
     while ((arr = regex.exec(str)) !== null) {
       // eslint-disable-next-line no-console
       console.log('[DEBUG] Parsed regular expression', arr);

src/packwerk.ts

@@ -47,7 +47,7 @@ export class Packwerk {
     let currentPath = getCurrentPath(fileName);
     let relativeFileName = fileName.replace(currentPath + '/', '');
 
-    let onDidExec = (error: Error, stdout: string, stderr: string) => {
+    let onDidExec = (error: Error | null, stdout: string, stderr: string) => {
       // eslint-disable-next-line no-console
       console.debug('[DEBUG] Finished running command, in onDidExec');
       // eslint-disable-next-line no-console
@@ -64,7 +64,7 @@ export class Packwerk {
 
       let entries: [vscode.Uri, vscode.Diagnostic[]][] = [];
       packwerk.files.forEach((file: PackwerkFile) => {
-        let diagnostics = [];
+        let diagnostics: vscode.Diagnostic[] = [];
         file.violations.forEach((offence: PackwerkViolation) => {
           const loc = offence.location;
           const range = new vscode.Range(
@@ -131,21 +131,21 @@ export class Packwerk {
   private executePackwerkCheck(
     fileName: string,
     fileContents: string,
-    options: cp.ExecOptions,
-    cb: (err: Error, stdout: string, stderr: string) => void
+    options: cp.ExecOptionsWithStringEncoding,
+    cb: (err: Error | null, stdout: string, stderr: string) => void
   ): cp.ChildProcess {
     let command = `${this.config.executable} ${fileName}`;
     // eslint-disable-next-line no-console
     console.debug(`[DEBUG] Running command ${command}`);
 
     let child = cp.exec(command, options, cb);
-    child.stdin.write(fileContents); // why do we need this?
-    child.stdin.end();
+    child.stdin!.write(fileContents); // why do we need this?
+    child.stdin!.end();
     return child;
   }
 
   private parse(output: string): PackwerkOutput | null {
-    let packwerk: PackwerkOutput;
+    let packwerk: PackwerkOutput | null = null;
     if (output.length < 1) {
       // eslint-disable-next-line no-console
       console.debug(`[DEBUG] Output is ${output}`);
@@ -175,7 +175,7 @@ export class Packwerk {
     return packwerk;
   }
 
-  private reportError(error: Error, stderr: string): boolean {
+  private reportError(error: Error | null, stderr: string): boolean {
     let errorOutput = stderr.toString();
     if (error && (<any>error).code === 'ENOENT') {
       vscode.window.showWarningMessage(

src/taskQueue.ts

@@ -31,7 +31,7 @@ export class Task {
 
   public run(): Promise<void> {
     if (this.isCanceled) {
-      return;
+      return Promise.resolve();
     }
     let task = this;
     return new Promise<void>((resolve, reject) => {
@@ -117,7 +117,7 @@ export class TaskQueue {
       try {
         await task.run();
       } catch (e) {
-        console.error('Error while running packwerk: ', e.message, e.stack);
+        console.error('Error while running packwerk: ', e);
       }
       this.tasks.shift();
     }

test/configuration.test.ts

@@ -1,6 +1,6 @@
 import { expect } from 'chai';
 import * as cp from 'child_process';
-import * as pq from 'proxyquire';
+import pq from 'proxyquire';
 import * as vsStub from 'vscode';
 
 // override vs.workspace.getConfiguration to return default values for each of the extension's
@@ -9,19 +9,19 @@ const { getConfiguration: _getConfiguration } = vsStub.workspace;
 
 vsStub.workspace.getConfiguration = (
   section?: string,
-  resource?: vsStub.Uri | null
+  scope?: vsStub.ConfigurationScope | null
 ): any => {
   if (section !== 'ruby.packwerk') {
-    return _getConfiguration(section, resource);
+    return _getConfiguration(section, scope);
   }
 
-  const defaultConfig = {
+  const defaultConfig: Record<string, unknown> = {
     onSave: true,
   };
 
   return {
     get: <T>(key: string, defaultValue: T): T =>
-      defaultConfig[key] || defaultValue,
+      (defaultConfig[key] as T) || defaultValue,
   };
 };
 

test/taskQueue.test.ts

@@ -5,7 +5,7 @@ import * as vscode from 'vscode';
 class TestTaskWrapper {
   public readonly url: vscode.Uri;
   public readonly task: Task;
-  public token?: TaskToken;
+  public token!: TaskToken;
   public isBodyCalled: boolean = false;
   public isCancelCallbackCalled: boolean = false;
 

tsconfig.json

@@ -7,7 +7,12 @@
             "es6"
         ],
         "sourceMap": true,
-        "rootDir": "."
+        "rootDir": ".",
+        "strict": true,
+        "types": [
+            "node",
+            "mocha"
+        ]
     },
     "exclude": [
         "node_modules",