feat: add rule no-regexp-duplicate-named-groups (and bump to ES2025)

README.md

@@ -164,6 +164,7 @@ for configuration. Here's some examples:
 - [no-private-class-fields](./docs/no-private-class-fields.md)
 - [no-public-instance-class-fields](./docs/no-public-instance-class-fields.md)
 - [no-public-static-class-fields](./docs/no-public-static-class-fields.md)
+- [no-regexp-duplicate-named-groups](./docs/no-regexp-duplicate-named-groups.md)
 - [no-regexp-lookbehind](./docs/no-regexp-lookbehind.md)
 - [no-regexp-named-group](./docs/no-regexp-named-group.md)
 - [no-regexp-s-flag](./docs/no-regexp-s-flag.md)

docs/no-regexp-duplicate-named-groups.md

@@ -0,0 +1,24 @@
+# no-regexp-duplicate-named-groups
+
+This prevents the use of the RegExp duplicate named groups feature
+
+```js
+/(?<year>\d{4})-(?<month>\d{2})|(?<month>\d{2})-(?<year>\d{4})/;
+
+new RegExp('(?<year>\\d{4})-(?<month>\\d{2})|(?<month>\\d{2})-(?<year>\\d{4})')
+```
+
+These will not be allowed because they are not supported in the following browsers:
+
+ - Edge < 125
+ - Safari < 17
+ - Firefox < 129
+ - Chrome < 125
+
+
+## What is the Fix?
+
+You will have to avoid getting the same name out-of-the-box for an
+alternative group.
+
+This can be safely disabled if you intend to compile code with the `@babel/plugin-proposal-duplicate-named-capturing-groups-regex` Babel plugin.

docs/no-regexp-named-group.md

@@ -5,7 +5,7 @@ This prevents the use of the RegExp named groups feature
 ```js
 /(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/
 
-new RegExp('(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})')
+new RegExp('(?<year>\\d{4})-(?<month>\\d{2})-(?<day>\\d{2})')
 ```
 
 These will not be allowed because they are not supported in the following browsers:
@@ -22,7 +22,7 @@ If readability is the main concern, using non-named groups with array-destructur
 
 ```js
 // With named:
-const {year,month,day} = '2020-01-01'.match(/(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/).groups
+const {year, month, day} = '2020-01-01'.match(/(?<year>\d{4})-(?<month>\d{2})-(?<day>\d{2})/).groups
 
 // Without named
 const [_, year, month, day] = '2020-01-01'.match(/(\d{4})-(\d{2})-(\d{2})/) || []

lib/index.js

@@ -228,6 +228,14 @@ createRule(
   { ts: 2024 }
 );
 
+// ES2025
+createRule(
+  "no-regexp-duplicate-named-groups",
+  "edge < 125, safari < 17, firefox < 129, chrome < 125",
+  "disallow the use of RegExp duplicate named groups",
+  { ts: 2025 }
+);
+
 // Proposals...
 createRule(
   "no-do-expression",
@@ -247,7 +255,7 @@ createRule(
 
 module.exports.configs.recommended = {
   plugins: ["escompat"],
-  parserOptions: { ecmaVersion: 2024 },
+  parserOptions: { ecmaVersion: 2025 },
   rules: Object.keys(module.exports.rules).reduce(
     (o, r) => ((o["escompat/" + r] = ["error"]), o),
     {}
@@ -260,7 +268,7 @@ module.exports.configs["flat/recommended"] = {
     escompat: module.exports
   },
   languageOptions: {
-    ecmaVersion: 2024
+    ecmaVersion: 2025
   },
   rules: Object.keys(module.exports.rules).reduce(
     (o, r) => ((o["escompat/" + r] = ["error"]), o),

lib/rules/no-regexp-duplicate-named-groups.js

@@ -0,0 +1,30 @@
+'use strict';
+
+const hasDuplicateNamedGroups = s => /(\(\?<[_$\w]*?)>.*?\1>/.test(s)
+
+module.exports = (context, badBrowser) => ({
+  'Literal[regex]'(node) {
+    if (hasDuplicateNamedGroups(node.regex.pattern)) {
+      context.report(node, `RegExp duplicate named groups are not supported in ${badBrowser}`)
+    }
+  },
+  'CallExpression[callee.name="RegExp"], NewExpression[callee.name="RegExp"]'(node) {
+    const [source] = node.arguments;
+    if (
+      source &&
+      (
+        (
+          source.type === 'Literal' &&
+          typeof source.value === 'string' &&
+          hasDuplicateNamedGroups(source.value)
+        ) ||
+        (
+          source.type === 'TemplateLiteral' &&
+          source.quasis.some(({value: {raw}}) => hasDuplicateNamedGroups(raw))
+        )
+      )
+    ) {
+      context.report(node, `RegExp duplicate named groups are not supported in ${badBrowser}`)
+    }
+  }
+})

test/no-regexp-duplicate-named-groups.js

@@ -0,0 +1,52 @@
+'use strict';
+
+const rule = require('../lib/index').rules['no-regexp-duplicate-named-groups']
+const RuleTester = require('eslint').RuleTester
+
+const ruleTester = new RuleTester({languageOptions: {ecmaVersion: 2025}})
+
+ruleTester.run('no-regexp-duplicate-named-groups', rule, {
+  valid: [
+    {code: '/(?:a)/'},
+    {code: '/(?:a)/g'},
+    {code: 'RegExp("(?:a)b")'},
+    {code: 'RegExp("(?:a)b", "g")'},
+    {code: '/(?<name>a)/'},
+    {code: 'RegExp("(?<name>a)")'},
+    {code: '/(?<name>a)|(?<anotherName>a)/'},
+  ],
+  invalid: [
+    {
+      code: '/(?<name>a)|(?<name>b)/',
+      errors: [
+        {
+          message: 'RegExp duplicate named groups are not supported in undefined'
+        }
+      ]
+    },
+    {
+      code: 'new RegExp("(?<name>a)|(?<name>b)")',
+      errors: [
+        {
+          message: 'RegExp duplicate named groups are not supported in undefined'
+        }
+      ]
+    },
+    {
+      code: '/(?<$name>a)|(?<$name>b)/',
+      errors: [
+        {
+          message: 'RegExp duplicate named groups are not supported in undefined'
+        }
+      ]
+    },
+    {
+      code: '/(?<_name>)|(?<_name>)/',
+      errors: [
+        {
+          message: 'RegExp duplicate named groups are not supported in undefined'
+        }
+      ]
+    },
+  ]
+})