From cd261735b9e045e0ca547a8347cbc515281ba7d8 Mon Sep 17 00:00:00 2001
From: Bryan Mishkin <698306+bmish@users.noreply.github.com>
Date: Thu, 5 Dec 2024 16:42:39 -0500
Subject: [PATCH] Stricter linting (#713)

---
 eslint.config.js           | 106 +++++++++++++++++++++++++++++++++----
 lib/dependency-versions.ts |   8 +--
 lib/output.ts              |  10 ++--
 3 files changed, 104 insertions(+), 20 deletions(-)

diff --git a/eslint.config.js b/eslint.config.js
index 26a91e8..471084b 100644
--- a/eslint.config.js
+++ b/eslint.config.js
@@ -18,19 +18,12 @@ export default tseslint.config(
   eslintPluginN.configs['flat/recommended'],
   eslintPluginPrettierRecommended,
   eslintPluginUnicorn.configs['flat/recommended'],
-  ...tseslint.configs.recommendedTypeChecked,
+  ...tseslint.configs.strictTypeChecked,
 
   // Individual rules:
   {
     rules: {
-      'import/extensions': ['error', 'always'],
-      'import/no-unresolved': 'off',
-
       'n/no-missing-import': 'off', // bug with recognizing node: prefix https://github.com/mysticatea/eslint-plugin-node/issues/275
-      'n/no-unsupported-features/es-syntax': [
-        'error',
-        { ignores: ['modules'] },
-      ],
 
       'prettier/prettier': [
         'error',
@@ -39,11 +32,102 @@ export default tseslint.config(
         },
       ],
 
+      // unicorn rules:
       'unicorn/import-style': 'off',
       'unicorn/no-useless-undefined': 'off', // We use a lot of `return undefined` to satisfy the `consistent-return` rule.
 
+      // typescript-eslint rules:
       '@typescript-eslint/prefer-readonly': 'error',
       '@typescript-eslint/require-array-sort-compare': 'error',
+
+      // Optional eslint rules:
+      'array-callback-return': 'error',
+      'block-scoped-var': 'error',
+      complexity: 'error',
+      'consistent-return': 'error',
+      curly: 'error',
+      'default-case': 'error',
+      eqeqeq: 'error',
+      'func-style': ['error', 'declaration'],
+      'new-parens': 'error',
+      'no-async-promise-executor': 'error',
+      'no-eval': 'error',
+      'no-extend-native': 'error',
+      'no-extra-bind': 'error',
+      'no-implicit-coercion': 'error',
+      'no-implied-eval': 'error',
+      'no-lone-blocks': 'error',
+      'no-multiple-empty-lines': 'error',
+      'no-new-func': 'error',
+      'no-new-wrappers': 'error',
+      'no-octal-escape': 'error',
+      'no-param-reassign': ['error', { props: true }],
+      'no-return-assign': 'error',
+      'no-return-await': 'error',
+      'no-self-compare': 'error',
+      'no-sequences': 'error',
+      'no-shadow-restricted-names': 'error',
+      'no-template-curly-in-string': 'error',
+      'no-throw-literal': 'error',
+      'no-unused-expressions': [
+        'error',
+        { allowShortCircuit: true, allowTernary: true },
+      ],
+      'no-use-before-define': ['error', 'nofunc'],
+      'no-useless-call': 'error',
+      'no-useless-catch': 'error',
+      'no-useless-computed-key': 'error',
+      'no-useless-concat': 'error',
+      'no-useless-constructor': 'error',
+      'no-useless-escape': 'error',
+      'no-useless-rename': 'error',
+      'no-useless-return': 'error',
+      'no-var': 'error',
+      'no-void': 'error',
+      'no-with': 'error',
+      'object-shorthand': 'error',
+      'prefer-const': 'error',
+      'prefer-numeric-literals': 'error',
+      'prefer-promise-reject-errors': 'error',
+      'prefer-rest-params': 'error',
+      'prefer-spread': 'error',
+      'prefer-template': 'error',
+      quotes: [
+        'error',
+        'single', // Must match quote style enforced by prettier.
+        // Disallow unnecessary template literals.
+        { avoidEscape: true, allowTemplateLiterals: false },
+      ],
+      radix: 'error',
+      'require-atomic-updates': 'error',
+      'require-await': 'error',
+      'spaced-comment': ['error', 'always', { markers: ['*', '!'] }],
+      'sort-vars': 'error',
+      yoda: 'error',
+
+      // import rules:
+      'import/default': 'error',
+      'import/export': 'error',
+      'import/extensions': ['error', 'always'],
+      'import/first': 'error',
+      'import/named': 'error',
+      'import/namespace': 'error',
+      'import/newline-after-import': 'error',
+      'import/no-absolute-path': 'error',
+      'import/no-cycle': 'error',
+      'import/no-deprecated': 'error',
+      'import/no-duplicates': 'error',
+      'import/no-dynamic-require': 'error',
+      'import/no-mutable-exports': 'error',
+      'import/no-named-as-default': 'error',
+      'import/no-named-as-default-member': 'error',
+      'import/no-named-default': 'error',
+      'import/no-self-import': 'error',
+      'import/no-unassigned-import': 'error',
+      'import/no-unresolved': 'off',
+      'import/no-unused-modules': 'error',
+      'import/no-useless-path-segments': 'error',
+      'import/no-webpack-loader-syntax': 'error',
     },
 
     // typescript-eslint parser options:
@@ -53,6 +137,10 @@ export default tseslint.config(
         tsconfigRootDir: import.meta.dirname,
       },
     },
+
+    linterOptions: {
+      reportUnusedDisableDirectives: 'error',
+    },
   },
 
   // Disabling type-checking for JS files:
@@ -67,7 +155,7 @@ export default tseslint.config(
       // compiled output
       'dist/**',
 
-      // coverage
+      // test coverage
       'coverage/**',
     ],
   },
diff --git a/lib/dependency-versions.ts b/lib/dependency-versions.ts
index 59274cd..0c6cbdb 100644
--- a/lib/dependency-versions.ts
+++ b/lib/dependency-versions.ts
@@ -59,6 +59,7 @@ export function calculateVersionsForEachDependency(
   return dependenciesToVersionsSeen;
 }
 
+// eslint-disable-next-line complexity
 function recordDependencyVersionsForPackageJson(
   dependenciesToVersionsSeen: DependenciesToVersionsSeen,
   package_: Package,
@@ -190,12 +191,6 @@ export function calculateDependenciesAndVersions(
   return [...dependencyVersions.entries()]
     .sort((a, b) => a[0].localeCompare(b[0]))
     .flatMap(([dependency, versionObjectsForDep]) => {
-      /* istanbul ignore if */
-      if (!versionObjectsForDep) {
-        // Should always exist at this point, this if statement is just to please TypeScript.
-        return [];
-      }
-
       // Check what versions we have seen for this dependency.
       let versions = versionObjectsForDep
         .filter((versionObject) => !versionObject.isLocalPackageVersion)
@@ -335,6 +330,7 @@ function writeDependencyVersion(
   );
 }
 
+// eslint-disable-next-line complexity
 export function fixVersionsMismatching(
   packages: readonly Package[],
   mismatchingVersions: readonly DependencyAndVersions[],
diff --git a/lib/output.ts b/lib/output.ts
index cb085d2..842f580 100644
--- a/lib/output.ts
+++ b/lib/output.ts
@@ -41,9 +41,9 @@ export function dependenciesToMismatchSummary(
           );
           const packageListSentence =
             usageCount > 3
-              ? `${packageNames.slice(0, 3).join(', ')}, and ${
-                  usageCount - 3
-                } other${usageCount - 3 === 1 ? '' : 's'}`
+              ? `${packageNames.slice(0, 3).join(', ')}, and ${String(
+                  usageCount - 3,
+                )} other${usageCount - 3 === 1 ? '' : 's'}`
               : packageNames.join(', ');
           return [
             chalk.redBright(versionObject.version),
@@ -59,7 +59,7 @@ export function dependenciesToMismatchSummary(
     .join('');
 
   return [
-    `Found ${mismatchingDependencyVersions.length} ${
+    `Found ${String(mismatchingDependencyVersions.length)} ${
       mismatchingDependencyVersions.length === 1 ? 'dependency' : 'dependencies'
     } with mismatching versions across the workspace. Fix with \`--fix\`.`,
     tables,
@@ -95,7 +95,7 @@ export function dependenciesToFixedSummary(dependencies: Dependencies): string {
     })
     .sort((a, b) => a.dependency.localeCompare(b.dependency));
 
-  return `Fixed versions for ${dependenciesAndFixedVersions.length} ${
+  return `Fixed versions for ${String(dependenciesAndFixedVersions.length)} ${
     dependenciesAndFixedVersions.length === 1 ? 'dependency' : 'dependencies'
   }: ${dependenciesAndFixedVersions
     .map((object) => `${object.dependency}@${object.version}`)