Use the built-in class fields and private methods rules in ESLint 8

.github/workflows/ci.yml

@@ -197,18 +197,15 @@ jobs:
       - name: Downgrade Jest for node <= 10
         if: matrix.node-version == '6' || matrix.node-version == '8' || matrix.node-version == '10'
         run: |
-          yarn remove jest
-          yarn add --dev jest@24
+          yarn up jest@24
           # Deduplicate dependencies, because duplicate copies of graceful-fs cause
           # problems with the "path" module: https://github.com/facebook/jest/issues/9656
           yarn dedupe
-      - name: Downgrade Jest for node == 12
+      - name: Downgrade Jest and jest-light-runner for node == 12
         if: matrix.node-version == '12'
         run: |
-          yarn remove jest
-          yarn remove jest-light-runner
-          yarn add --dev jest@28
-          yarn add --dev jest-light-runner@0.3.0
+          yarn up jest@28
+          yarn up jest-light-runner@0.3.0
           # Deduplicate dependencies, because duplicate copies of graceful-fs cause
           # problems with the "path" module: https://github.com/facebook/jest/issues/9656
           yarn dedupe
@@ -430,3 +427,25 @@ jobs:
           node-version: 16.6
       - name: Test Node.js 16.6
         run: yarn test:runtime:node
+
+  eslint7-test:
+    name: Test @babel/eslint-* with ESLint 7.5.0
+    needs: build
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+      - name: Use Node.js latest
+        uses: actions/setup-node@v3
+        with:
+          node-version: "*"
+          cache: "yarn"
+      - name: Install
+        run: yarn install
+      - uses: actions/download-artifact@v3
+        with:
+          name: babel-artifact
+      - name: Downgrade ESLint to 7.5.0
+        run: yarn up eslint@7.5.0
+      - name: Run babel/eslint tests
+        run: node ./node_modules/.bin/jest eslint

babel.config.js

@@ -67,7 +67,6 @@ module.exports = function (api) {
   let ignoreLib = true;
   let includeRegeneratorRuntime = false;
   let needsPolyfillsForOldNode = false;
-  let dynamicESLintVersionCheck = false;
 
   let transformRuntimeOptions;
 
@@ -118,7 +117,6 @@ module.exports = function (api) {
       needsPolyfillsForOldNode = true;
       break;
     case "test-legacy": // In test-legacy environment, we build babel on latest node but test on minimum supported legacy versions
-      dynamicESLintVersionCheck = true;
     // fall through
     case "production":
       // Config during builds before publish.
@@ -128,12 +126,10 @@ module.exports = function (api) {
     case "test":
       targets = { node: "current" };
       needsPolyfillsForOldNode = true;
-      dynamicESLintVersionCheck = true;
       break;
     case "development":
       envOpts.debug = true;
       targets = { node: "current" };
-      dynamicESLintVersionCheck = true;
       break;
   }
 
@@ -291,10 +287,6 @@ module.exports = function (api) {
         exclude: /regenerator-runtime/,
         plugins: [["@babel/transform-runtime", transformRuntimeOptions]],
       },
-      dynamicESLintVersionCheck && {
-        test: ["./eslint/*/src"].map(normalize),
-        plugins: [pluginDynamicESLintVersionCheck],
-      },
     ].filter(Boolean),
   };
 
@@ -815,33 +807,6 @@ function pluginBabelParserTokenType({
   };
 }
 
-// Transforms
-//    ESLINT_VERSION
-// to
-//    process.env.ESLINT_VERSION_FOR_BABEL
-//      ? parseInt(process.env.ESLINT_VERSION_FOR_BABEL, 10)
-//      : ESLINT_VERSION
-function pluginDynamicESLintVersionCheck({ template }) {
-  const transformed = new WeakSet();
-
-  return {
-    visitor: {
-      ReferencedIdentifier(path) {
-        if (path.node.name !== "ESLINT_VERSION") return;
-
-        if (transformed.has(path.node)) return;
-        transformed.add(path.node);
-
-        path.replaceWith(template.expression.ast`
-          process.env.ESLINT_VERSION_FOR_BABEL
-            ? parseInt(process.env.ESLINT_VERSION_FOR_BABEL, 10)
-            : ${path.node}
-        `);
-      },
-    },
-  };
-}
-
 // Inject `0 && exports.foo = 0` hints for the specified exports,
 // to help the Node.js CJS-ESM interop. This is only
 // needed when compiling ESM re-exports to CJS in `lazy` mode.

eslint/babel-eslint-parser/package.json

@@ -31,14 +31,14 @@
     "eslint": "^7.5.0 || ^8.0.0"
   },
   "dependencies": {
-    "eslint-scope": "^5.1.1",
-    "eslint-visitor-keys": "^2.1.0",
+    "@nicolo-ribaudo/eslint-scope-5-internals": "condition:BABEL_8_BREAKING ? : 5.1.1-v1",
+    "eslint-scope": "condition:BABEL_8_BREAKING ? ^7.1.1 : ",
+    "eslint-visitor-keys": "condition:BABEL_8_BREAKING ? ^3.3.0 : ^2.1.0",
     "semver": "condition:BABEL_8_BREAKING ? ^7.3.4 : ^6.3.0"
   },
   "devDependencies": {
     "@babel/core": "workspace:^",
     "dedent": "^0.7.0",
-    "eslint": "^7.27.0",
-    "eslint-8": "npm:eslint@^8.0.0"
+    "eslint": "^8.22.0"
   }
 }

eslint/babel-eslint-parser/src/analyze-scope.cjs

@@ -1,7 +1,12 @@
-const escope = require("eslint-scope");
-const { Definition } = require("eslint-scope/lib/definition");
-const OriginalPatternVisitor = require("eslint-scope/lib/pattern-visitor");
-const OriginalReferencer = require("eslint-scope/lib/referencer");
+const {
+  Definition,
+  PatternVisitor: OriginalPatternVisitor,
+  Referencer: OriginalReferencer,
+  Scope,
+  ScopeManager,
+} = process.env.BABEL_8_BREAKING
+  ? require("eslint-scope")
+  : require("@nicolo-ribaudo/eslint-scope-5-internals");
 const { getKeys: fallback } = require("eslint-visitor-keys");
 
 let visitorKeysMap;
@@ -236,7 +241,7 @@ class Referencer extends OriginalReferencer {
     }
 
     const parentScope = this.scopeManager.__currentScope;
-    const scope = new escope.Scope(
+    const scope = new Scope(
       this.scopeManager,
       "type-parameters",
       parentScope,
@@ -349,7 +354,7 @@ module.exports = function analyzeScope(ast, parserOptions, client) {
 
   options.childVisitorKeys = client.getVisitorKeys();
 
-  const scopeManager = new escope.ScopeManager(options);
+  const scopeManager = new ScopeManager(options);
   const referencer = new Referencer(options, scopeManager, client);
 
   referencer.visit(ast);