refactor: apply stricter rules

.eslintrc.js

@@ -12,9 +12,7 @@ module.exports = {
   root: true,
   extends: ['@1stg'],
   rules: {
-    '@typescript-eslint/naming-convention': 0,
+    // `strictNullChecks` is required
     '@typescript-eslint/no-unnecessary-condition': 0,
-    '@typescript-eslint/no-unsafe-assignment': 0,
-    '@typescript-eslint/unbound-method': 0, // See https://github.com/typescript-eslint/typescript-eslint/issues/636
   },
 }

package.json

@@ -18,17 +18,17 @@
     "lint:es": "cross-env PARSER_NO_WATCH=true eslint . --cache --ext js,md,ts -f friendly",
     "lint:ts": "tslint -p . -t stylish",
     "lint:tsc": "tsc",
-    "postinstall": "yarn-deduplicate || exit 0",
+    "postinstall": "yarn-deduplicate --strategy fewer || exit 0",
     "prelint": "yarn build:ts",
     "prerelease": "yarn build",
     "pretest": "yarn clean",
     "release": "lerna publish --conventional-commits --create-release github --yes",
-    "test": "ts-node --skip-ignore node_modules/.bin/jest",
+    "test": "jest",
     "typecov": "type-coverage"
   },
   "devDependencies": {
-    "@1stg/lib-config": "^1.1.8",
-    "@1stg/tslint-config": "^1.0.1",
+    "@1stg/lib-config": "^1.1.9",
+    "@1stg/tslint-config": "^1.1.0",
     "@types/eslint": "^7.2.6",
     "@types/jest": "^26.0.20",
     "@types/node": "^14.14.31",
@@ -48,6 +48,7 @@
     "yarn-deduplicate": "^3.1.0"
   },
   "resolutions": {
+    "@babel/core": "^7.13.8",
     "prettier": "^2.2.1",
     "tslib": "^2.1.0"
   },

packages/eslint-mdx/src/helper.ts

@@ -27,8 +27,8 @@ export const isJsxNode = (node: { type: string }): node is JsxNode =>
 export const normalizeParser = (parser?: ParserOptions['parser']) => {
   if (parser) {
     if (typeof parser === 'string') {
-      // eslint-disable-next-line @typescript-eslint/no-require-imports
-      parser = require(parser)
+      // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
+      parser = require(parser) as ParserOptions['parser']
     }
 
     if (typeof parser === 'object') {
@@ -50,12 +50,14 @@ export const normalizeParser = (parser?: ParserOptions['parser']) => {
   for (const fallback of FALLBACK_PARSERS) {
     try {
       // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
-      const fallbackParser: Linter.ParserModule = require(fallback)
+      const fallbackParser = require(fallback) as Linter.ParserModule
       /* istanbul ignore next */
       const parserFn =
         'parseForESLint' in fallbackParser
-          ? fallbackParser.parseForESLint
-          : fallbackParser.parse
+          ? // eslint-disable-next-line @typescript-eslint/unbound-method
+            fallbackParser.parseForESLint
+          : // eslint-disable-next-line @typescript-eslint/unbound-method
+            fallbackParser.parse
       /* istanbul ignore else */
       if (parserFn) {
         parsers.unshift(parserFn)

packages/eslint-mdx/src/parser.ts

@@ -222,9 +222,9 @@ export class Parser {
       try {
         program = parser(code, this._options)
         break
-      } catch (e) {
+      } catch (err) {
         if (!parseError) {
-          parseError = e as Error
+          parseError = err as Error
         }
       }
     }
@@ -387,4 +387,5 @@ export class Parser {
 
 export const parser = new Parser()
 
+// eslint-disable-next-line @typescript-eslint/unbound-method
 export const { parse, parseForESLint } = parser

packages/eslint-plugin-mdx/src/configs/overrides.ts

@@ -4,8 +4,8 @@ import { getGlobals } from './helper'
 let rebass: typeof import('rebass') | string[]
 
 try {
-  // eslint-disable-next-line @typescript-eslint/no-require-imports
-  rebass = require('rebass')
+  // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
+  rebass = require('rebass') as typeof rebass
 } catch {
   // `rebass`(or `reflexbox` actually) requires `react` as peerDependency, but not all projects using `mdx` are `React` based, so we fallback to hardcoded `rebass` Components here
   /* istanbul ignore next */

packages/eslint-plugin-mdx/src/rules/helper.ts

@@ -27,11 +27,11 @@ export const requirePkg = <T>(
   let error: Error
   for (const pkg of packages) {
     try {
-      // eslint-disable-next-line @typescript-eslint/no-var-requires, @typescript-eslint/no-require-imports, @typescript-eslint/no-unsafe-return
-      return require(pkg)
+      // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
+      return require(pkg) as T
     } catch (err) {
       if (!error) {
-        error = err
+        error = err as Error
       }
     }
   }
@@ -53,10 +53,10 @@ export const getRemarkProcessor = (searchFrom: string, isMdx: boolean) => {
   }
 
   /* istanbul ignore next */
-  const { config, filepath }: Partial<CosmiconfigResult> =
-    searchSync(searchFrom) || {}
+  const result: Partial<CosmiconfigResult> = searchSync(searchFrom) || {}
   /* istanbul ignore next */
-  const { plugins = [], settings }: Partial<RemarkConfig> = config || {}
+  const { plugins = [], settings } = (result.config ||
+    {}) as Partial<RemarkConfig>
 
   try {
     // disable this rule automatically since we already have a parser option `extensions`
@@ -80,7 +80,7 @@ export const getRemarkProcessor = (searchFrom: string, isMdx: boolean) => {
       return processor.use(
         /* istanbul ignore next */
         typeof plugin === 'string'
-          ? requirePkg(plugin, 'remark', filepath)
+          ? requirePkg(plugin, 'remark', result.filepath)
           : plugin,
         ...pluginSettings,
       )