use babel for acorn-node itself

Author: goto-bus-stop

.gitignore

@@ -28,3 +28,5 @@ node_modules
 package-lock.json
 
 lib/*
+/index.js
+/walk.js

package.json

@@ -45,6 +45,7 @@
     "build:acorn-class-fields": "babel node_modules/acorn-class-fields --out-dir lib/acorn-class-fields",
     "build:acorn-static-class-features": "babel node_modules/acorn-static-class-features --out-dir lib/acorn-static-class-features",
     "build:acorn-private-class-elements": "babel node_modules/acorn-private-class-elements --out-dir lib/acorn-private-class-elements",
+    "build:self": "babel src --out-dir .",
     "build": "npm-run-all --parallel build:*"
   },
   "standard": {

index.js renamed to src/index.js

@@ -1,8 +1,7 @@
 var acorn = require('acorn')
-var xtend = require('xtend')
-var setPrototypeOf = require('setprototypeof')
 
 var CJSParser = acorn.Parser
+  // Required paths should be relative to the package root, because Babel outputs this file there.
   .extend(require('./lib/acorn-class-fields'))
   .extend(require('./lib/acorn-static-class-features'))
   .extend(require('./lib/acorn-numeric-separator'))
@@ -11,28 +10,29 @@ var ESModulesParser = CJSParser
 
 function mapOptions (opts) {
   if (!opts) opts = {}
-  return xtend({
+  return {
     ecmaVersion: 2020,
     allowHashBang: true,
-    allowReturnOutsideFunction: true
-  }, opts)
+    allowReturnOutsideFunction: true,
+    ...opts
+  }
 }
 
 function defaultOptionsPlugin (P) {
-  function DefaultOptionsParser (opts, src) {
-    P.call(this, mapOptions(opts), src)
+  return class DefaultOptionsParser extends P {
+    constructor(opts, src) {
+      super(mapOptions(opts), src)
+    }
   }
-  setPrototypeOf(DefaultOptionsParser, P)
-  DefaultOptionsParser.prototype = P.prototype
-  return DefaultOptionsParser
 }
 
 function getParser (opts) {
   if (!opts) opts = {}
   return opts.sourceType === 'module' ? ESModulesParser : CJSParser
 }
 
-module.exports = exports = xtend(acorn, {
+module.exports = exports = {
+  ...acorn,
   Parser: CJSParser,
   ESModulesParser: ESModulesParser,
 
@@ -45,4 +45,4 @@ module.exports = exports = xtend(acorn, {
   tokenizer: function tokenizer (src, opts) {
     return getParser(opts).tokenizer(src, opts)
   }
-})
+}

walk.js renamed to src/walk.js

@@ -1,7 +1,8 @@
-var xtend = require('xtend')
 var walk = require('acorn-walk')
 
-var base = xtend(walk.base)
+var base = {
+  ...walk.base
+}
 
 function simple (node, visitors, baseVisitor, state, override) {
   return walk.simple(node, visitors, baseVisitor || base, state, override)