feat: support ESLint 8.x

BREAKING CHANGE: Requires Node@^12.22.0 || ^14.17.0 || >=16.0.0
BREAKING CHANGE: Requires ESLint@^8.0.0-0

Author: MichaelDeBoey

.babelrc

@@ -8,7 +8,7 @@
       "@babel/preset-env",
       {
         "targets": {
-          "node": 10
+          "node": 12
         }
       }
     ]

.travis.yml

@@ -1,7 +1,7 @@
 language: node_js
 node_js:
   - node
-  - 10
+  - 12
 before_install:
   - npm config set depth 0
 notifications:

package.json

@@ -10,18 +10,18 @@
   },
   "description": "Flowtype linting rules for ESLint.",
   "devDependencies": {
-    "@babel/cli": "^7.15.4",
-    "@babel/core": "^7.15.5",
-    "@babel/node": "^7.15.4",
+    "@babel/cli": "^7.15.7",
+    "@babel/core": "^7.15.8",
+    "@babel/eslint-parser": "^7.15.8",
+    "@babel/node": "^7.15.8",
     "@babel/plugin-proposal-object-rest-spread": "^7.15.6",
-    "@babel/preset-env": "^7.15.6",
+    "@babel/preset-env": "^7.15.8",
     "@babel/register": "^7.15.3",
     "ajv": "^8.6.3",
-    "babel-eslint": "^10.1.0",
     "babel-plugin-add-module-exports": "^1.0.4",
     "chai": "^4.3.4",
     "eclint": "^2.8.1",
-    "eslint": "^7.32.0",
+    "eslint": "^8.0.0",
     "eslint-config-canonical": "^27.0.1",
     "gitdown": "^3.1.4",
     "glob": "^7.1.7",
@@ -32,7 +32,7 @@
     "semantic-release": "^17.4.7"
   },
   "engines": {
-    "node": "^10.12.0 || >=12.0.0"
+    "node": "^12.22.0 || ^14.17.0 || >=16.0.0"
   },
   "husky": {
     "hooks": {
@@ -48,7 +48,7 @@
   "main": "./dist/index.js",
   "name": "eslint-plugin-flowtype",
   "peerDependencies": {
-    "eslint": "^7.32.0"
+    "eslint": "^8.0.0"
   },
   "repository": {
     "type": "git",

src/rules/noUnusedExpressions.js

@@ -1,7 +1,8 @@
 // A wrapper around ESLint's core rule no-unused-expressions, additionally ignores type cast
 // expressions.
+import { builtinRules } from 'eslint/use-at-your-own-risk';
 
-import coreNOE from 'eslint/lib/rules/no-unused-expressions';
+const coreNOE = builtinRules.get('no-unused-expressions');
 
 const meta = coreNOE.meta;
 

tests/rules/assertions/defineFlowType.js

@@ -1,7 +1,7 @@
-import {
-  RuleTester,
-} from 'eslint';
-import noUndefRule from 'eslint/lib/rules/no-undef';
+import { RuleTester } from 'eslint';
+import { builtinRules } from 'eslint/use-at-your-own-risk';
+
+const noUndefRule = builtinRules.get('no-undef');
 
 const VALID_WITH_DEFINE_FLOW_TYPE = [
   {
@@ -198,7 +198,7 @@ const ALWAYS_VALID = [
  */
 {
   const ruleTester = new RuleTester({
-    parser: require.resolve('babel-eslint'),
+    parser: require.resolve('@babel/eslint-parser'),
   });
 
   ruleTester.run('no-undef must not trigger an error in these cases', noUndefRule, {
@@ -209,7 +209,7 @@ const ALWAYS_VALID = [
 
 {
   const ruleTester = new RuleTester({
-    parser: require.resolve('babel-eslint'),
+    parser: require.resolve('@babel/eslint-parser'),
   });
 
   ruleTester.run('no-undef must trigger an error when define-flow-type is not used in these cases', noUndefRule, {

tests/rules/assertions/useFlowType.js

@@ -1,9 +1,9 @@
-import {
-  RuleTester,
-} from 'eslint';
-import noUnusedVarsRule from 'eslint/lib/rules/no-unused-vars';
+import { RuleTester } from 'eslint';
+import { builtinRules } from 'eslint/use-at-your-own-risk';
 import useFlowType from '../../../src/rules/useFlowType';
 
+const noUnusedVarsRule = builtinRules.get('no-unused-vars');
+
 const VALID_WITH_USE_FLOW_TYPE = [
   {
     code: 'declare class A {}',
@@ -92,7 +92,7 @@ const ALWAYS_VALID = [
  */
 {
   const ruleTester = new RuleTester({
-    parser: require.resolve('babel-eslint'),
+    parser: require.resolve('@babel/eslint-parser'),
   });
 
   ruleTester.run('no-unused-vars must not trigger an error in these cases', noUnusedVarsRule, {
@@ -103,7 +103,7 @@ const ALWAYS_VALID = [
 
 {
   const ruleTester = new RuleTester({
-    parser: require.resolve('babel-eslint'),
+    parser: require.resolve('@babel/eslint-parser'),
   });
 
   ruleTester.run('no-unused-vars must trigger an error in these cases', noUnusedVarsRule, {
@@ -117,7 +117,7 @@ const ALWAYS_VALID = [
 
 {
   const ruleTester = new RuleTester({
-    parser: require.resolve('babel-eslint'),
+    parser: require.resolve('@babel/eslint-parser'),
     rules: {
       'use-flow-type': 1,
     },

tests/rules/index.js

@@ -60,7 +60,7 @@ const reportingRules = [
   'valid-syntax',
 ];
 
-const parser = require.resolve('babel-eslint');
+const parser = require.resolve('@babel/eslint-parser');
 const ajv = new Ajv({
   verbose: true,
 });