chore: Upgrade last package (ecmascript) to ES2020 and ES modules.

Author: pdubroy

.eslintrc.cjs

@@ -1,7 +1,7 @@
 module.exports = {
   parserOptions: {
-    ecmaVersion: 6,
-    sourceType: 'script'
+    ecmaVersion: 11, // es2020
+    sourceType: 'module'
   },
 
   // To minimize dependencies on Node- or browser-specific features, leave the

examples/csv/index.js

@@ -1,7 +1,5 @@
 /* eslint-env node */
 
-'use strict';
-
 const assert = require('assert');
 const fs = require('fs');
 const {join} = require('path');

examples/ecmascript/compile.js

@@ -1,16 +1,11 @@
 /* eslint-env node */
 
-'use strict';
+import assert from 'node:assert/strict';
+import fs from 'node:fs';
 
-// --------------------------------------------------------------------
-// Imports
-// --------------------------------------------------------------------
-
-const fs = require('fs');
-const path = require('path');
-
-const es5 = require('./src/es5');
-const ohm = require('ohm-js');
+import * as es5 from './src/es5.js';
+import initES6 from './src/es6.js';
+import * as ohm from 'ohm-js';
 
 // --------------------------------------------------------------------
 // Helpers
@@ -20,19 +15,6 @@ function removeShebang(source) {
   return source.slice(0, 2) === '#!' ? source.replace('#!', '//') : source;
 }
 
-function loadModule(name) {
-  const ns = {ES5: es5.grammar};
-  if (fs.existsSync(name)) {
-    return require(name)(ohm, ns, es5.semantics);
-  }
-  const relPath = path.join(__dirname, 'src', name);
-  const modulePath = require.resolve(relPath);
-  if (modulePath) {
-    return require(modulePath)(ohm, ns, es5.semantics);
-  }
-  throw new Error("Error: Cannot find grammar module '" + name + "'");
-}
-
 // --------------------------------------------------------------------
 // Main
 // --------------------------------------------------------------------
@@ -60,7 +42,8 @@ function compile(args) {
     }
   }
 
-  const lang = opts.grammar ? loadModule(opts.grammar) : es5;
+  assert(!opts.grammar || ['es5', 'es6'].includes(opts.grammar));
+  const lang = opts.grammar === 'es6' ? initES6(ohm, {ES5: es5.grammar}, es5.semantics) : es5;
 
   const files = filenames.map(name => {
     // If benchmarking, read in all the files at once, so that we can just time the matching.
@@ -104,8 +87,9 @@ function compile(args) {
   return null;
 }
 
-module.exports = compile;
+export {compile};
 
-if (require.main === module) {
+// `importa.meta.main` was added in Node v24.2.0.
+if (import.meta.main) {
   console.log(compile(process.argv.slice(2)));
 }

examples/ecmascript/index.js

@@ -1,3 +1 @@
-'use strict';
-
-module.exports = require('./src/es5');
+export * from './src/es5.js';

examples/ecmascript/package.json

@@ -2,6 +2,7 @@
   "name": "ohm-grammar-ecmascript",
   "version": "2.0.0",
   "description": "Ohm grammars for various editions of ECMAScript (aka JavaScript).",
+  "type": "module",
   "scripts": {
     "test": "ava"
   },

examples/ecmascript/src/es5.js

@@ -1,15 +1,8 @@
 /* eslint-env node */
 
-'use strict';
+import {readFileSync} from 'node:fs';
 
-// --------------------------------------------------------------------
-// Imports
-// --------------------------------------------------------------------
-
-const fs = require('fs');
-const path = require('path');
-
-const ohm = require('ohm-js');
+import * as ohm from 'ohm-js';
 
 // --------------------------------------------------------------------
 // Helpers
@@ -56,9 +49,9 @@ function nodeToES5(node, children) {
 }
 
 // Instantiate the ES5 grammar.
-const contents = fs.readFileSync(path.join(__dirname, 'es5.ohm'));
-const g = ohm.grammars(contents).ES5;
-const semantics = g.createSemantics();
+const contents = readFileSync(new URL('es5.ohm', import.meta.url));
+const grammar = ohm.grammars(contents).ES5;
+const semantics = grammar.createSemantics();
 
 semantics.addOperation('toES5()', {
   Program(_, sourceElements) {
@@ -116,7 +109,4 @@ function mergeBindings(...nodes) {
   return bindings;
 }
 
-module.exports = {
-  grammar: g,
-  semantics,
-};
+export {grammar, semantics};

examples/ecmascript/src/es5.test.mjs examples/ecmascript/src/es5.test.jsexamples/ecmascript/src/es5.test.mjs renamed to examples/ecmascript/src/es5.test.js

@@ -1,11 +1,12 @@
-import compile from '../compile.js';
-import es5 from './es5.js';
+/* global URL */
+
+import {compile} from '../compile.js';
+import * as es5 from './es5.js';
 
 import test from 'ava';
-import path from 'path';
+import {join} from 'node:path';
 
-const __dirname = path.dirname(new URL(import.meta.url).pathname);
-const testdataPath = filename => path.join(__dirname, 'testdata', filename);
+const testdataPath = filename => new URL(join('testdata', filename), import.meta.url);
 
 test('es5 - basic tests', t => {
   let results = es5.grammar.match('var x = 3; console.log(x)');

examples/ecmascript/src/es6.js

@@ -1,9 +1,6 @@
 /* eslint-env node */
 
-'use strict';
-
-const fs = require('fs');
-const path = require('path');
+import {readFileSync} from 'node:fs';
 
 const anyNodesMentionThis = (...nodes) => nodes.some(n => n.mentionsThis);
 
@@ -34,8 +31,8 @@ const toES5Actions = {
   },
 };
 
-module.exports = function(ohm, ns, s) {
-  const g = ohm.grammar(fs.readFileSync(path.join(__dirname, 'es6.ohm')).toString(), ns);
+export default function(ohm, ns, s) {
+  const g = ohm.grammar(readFileSync(new URL('es6.ohm', import.meta.url)).toString(), ns);
   const semantics = g.extendSemantics(s);
   semantics.addAttribute('mentionsThis', mentionsThisActions);
   semantics.extendOperation('toES5', toES5Actions);
@@ -44,4 +41,4 @@ module.exports = function(ohm, ns, s) {
     grammar: g,
     semantics,
   };
-};
+}

examples/ecmascript/src/es6.test.mjs examples/ecmascript/src/es6.test.jsexamples/ecmascript/src/es6.test.mjs renamed to examples/ecmascript/src/es6.test.js

@@ -1,8 +1,7 @@
-import fs from 'fs';
 import * as ohm from 'ohm-js';
 import test from 'ava';
 
-import es5 from './es5.js';
+import * as es5 from './es5.js';
 import initES6 from './es6.js';
 
 const es6 = initES6(ohm, {ES5: es5.grammar}, es5.semantics);
@@ -12,7 +11,7 @@ test('template literals', t => {
   const succeeds = str => {
     const result = es6.grammar.match(str);
     if (!result.succeeded()) {
-      console.error(result.message);
+      console.error(result.message); // eslint-disable-line no-console
     }
     return result.succeeded();
   };

examples/indentation-sensitive/index.js

@@ -16,7 +16,7 @@ const outline = grammar(
     spaces := (~newline space)*
   }
 `,
-    {IndentationSensitive}
+    {IndentationSensitive},
 );
 const semantics = outline.createSemantics().addOperation('toJS', {
   Items(items) {
@@ -65,15 +65,15 @@ test('errors', () => {
       number = digit+
     }
   `,
-      {IndentationSensitive}
+      {IndentationSensitive},
   );
 
   assert.is(g.match('if True:\n  3').succeeded(), true);
   assert.is(g.match('if True:\n  if False:\n    3').succeeded(), true);
   assert.is(g.match('if True:\n3').shortMessage, 'Line 2, col 1: expected an indented block');
   assert.is(
       g.match('if True:\n if False:\n 3').shortMessage,
-      'Line 3, col 2: expected an indented block'
+      'Line 3, col 2: expected an indented block',
   );
 });