Add rules for Upsert proposal (#311)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: ota-meshi <16508807+ota-meshi@users.noreply.github.com>
Co-authored-by: yosuke ota <otameshiyo23@gmail.com>

Author: Copilot

.changeset/no-map-prototype-getorinsert.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-es-x": minor
+---
+
+Add `es-x/no-map-prototype-getorinsert` rule

.changeset/no-map-prototype-getorinsertcomputed.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-es-x": minor
+---
+
+Add `es-x/no-map-prototype-getorinsertcomputed` rule

.changeset/no-weakmap-prototype-getorinsert.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-es-x": minor
+---
+
+Add `es-x/no-weakmap-prototype-getorinsert` rule

.changeset/no-weakmap-prototype-getorinsertcomputed.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-es-x": minor
+---
+
+Add `es-x/no-weakmap-prototype-getorinsertcomputed` rule

.changeset/witty-animals-buy.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-es-x": minor
+---
+
+Add `no-upsert` config

docs/configs/index.md

@@ -1044,7 +1044,7 @@ export default [
 disallow proposal ES2026 [Uint8Array to/from Base64 and Hex](https://github.com/tc39/proposal-arraybuffer-base64)\
 ⚠️ This config will be changed in the minor versions of this plugin.
 
-This configs includes rules for [es-x/no-uint8array-frombase64](../rules/no-uint8array-frombase64.md), [es-x/no-uint8array-fromhex](../rules/no-uint8array-fromhex.md), [es-x/no-uint8array-prototype-setfrombase64](../rules/no-uint8array-prototype-setfrombase64.md), [es-x/no-uint8array-prototype-setfromhex](../rules/no-uint8array-prototype-setfromhex.md), [es-x/no-uint8array-prototype-tobase64](../rules/no-uint8array-prototype-tobase64.md), and [es-x/no-uint8array-prototype-tohex](../rules/no-uint8array-prototype-tohex.md).
+This config includes the rules [es-x/no-uint8array-frombase64](../rules/no-uint8array-frombase64.md), [es-x/no-uint8array-fromhex](../rules/no-uint8array-fromhex.md), [es-x/no-uint8array-prototype-setfrombase64](../rules/no-uint8array-prototype-setfrombase64.md), [es-x/no-uint8array-prototype-setfromhex](../rules/no-uint8array-prototype-setfromhex.md), [es-x/no-uint8array-prototype-tobase64](../rules/no-uint8array-prototype-tobase64.md), and [es-x/no-uint8array-prototype-tohex](../rules/no-uint8array-prototype-tohex.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1070,7 +1070,7 @@ export default [
 disallow proposal ES2026 [Explicit Resource Management](https://github.com/tc39/proposal-explicit-resource-management)\
 ⚠️ This config will be changed in the minor versions of this plugin.
 
-This configs includes rules for [es-x/no-asyncdisposablestack](../rules/no-asyncdisposablestack.md), [es-x/no-disposablestack](../rules/no-disposablestack.md), [es-x/no-suppressederror](../rules/no-suppressederror.md), [es-x/no-symbol-asyncdispose](../rules/no-symbol-asyncdispose.md), [es-x/no-symbol-dispose](../rules/no-symbol-dispose.md), and [es-x/no-using-declarations](../rules/no-using-declarations.md).
+This config includes the rules [es-x/no-asyncdisposablestack](../rules/no-asyncdisposablestack.md), [es-x/no-disposablestack](../rules/no-disposablestack.md), [es-x/no-suppressederror](../rules/no-suppressederror.md), [es-x/no-symbol-asyncdispose](../rules/no-symbol-asyncdispose.md), [es-x/no-symbol-dispose](../rules/no-symbol-dispose.md), and [es-x/no-using-declarations](../rules/no-using-declarations.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1096,7 +1096,7 @@ export default [
 disallow proposal ES2026 Intl API [Intl Locale Info API](https://github.com/tc39/proposal-intl-locale-info)\
 ⚠️ This config will be changed in the minor versions of this plugin.
 
-This configs includes rules for [es-x/no-intl-locale-prototype-firstdayofweek](../rules/no-intl-locale-prototype-firstdayofweek.md), [es-x/no-intl-locale-prototype-getcalendars](../rules/no-intl-locale-prototype-getcalendars.md), [es-x/no-intl-locale-prototype-getcollations](../rules/no-intl-locale-prototype-getcollations.md), [es-x/no-intl-locale-prototype-gethourcycles](../rules/no-intl-locale-prototype-gethourcycles.md), [es-x/no-intl-locale-prototype-getnumberingsystems](../rules/no-intl-locale-prototype-getnumberingsystems.md), [es-x/no-intl-locale-prototype-gettextinfo](../rules/no-intl-locale-prototype-gettextinfo.md), [es-x/no-intl-locale-prototype-gettimezones](../rules/no-intl-locale-prototype-gettimezones.md), and [es-x/no-intl-locale-prototype-getweekinfo](../rules/no-intl-locale-prototype-getweekinfo.md).
+This config includes the rules [es-x/no-intl-locale-prototype-firstdayofweek](../rules/no-intl-locale-prototype-firstdayofweek.md), [es-x/no-intl-locale-prototype-getcalendars](../rules/no-intl-locale-prototype-getcalendars.md), [es-x/no-intl-locale-prototype-getcollations](../rules/no-intl-locale-prototype-getcollations.md), [es-x/no-intl-locale-prototype-gethourcycles](../rules/no-intl-locale-prototype-gethourcycles.md), [es-x/no-intl-locale-prototype-getnumberingsystems](../rules/no-intl-locale-prototype-getnumberingsystems.md), [es-x/no-intl-locale-prototype-gettextinfo](../rules/no-intl-locale-prototype-gettextinfo.md), [es-x/no-intl-locale-prototype-gettimezones](../rules/no-intl-locale-prototype-gettimezones.md), and [es-x/no-intl-locale-prototype-getweekinfo](../rules/no-intl-locale-prototype-getweekinfo.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1122,7 +1122,7 @@ export default [
 disallow proposal ES2026 [JSON.parse source text access](https://github.com/tc39/proposal-json-parse-with-source)\
 ⚠️ This config will be changed in the minor versions of this plugin.
 
-This configs includes rules for [es-x/no-json-israwjson](../rules/no-json-israwjson.md), [es-x/no-json-parse-reviver-context-parameter](../rules/no-json-parse-reviver-context-parameter.md), and [es-x/no-json-rawjson](../rules/no-json-rawjson.md).
+This config includes the rules [es-x/no-json-israwjson](../rules/no-json-israwjson.md), [es-x/no-json-parse-reviver-context-parameter](../rules/no-json-parse-reviver-context-parameter.md), and [es-x/no-json-rawjson](../rules/no-json-rawjson.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1143,11 +1143,37 @@ export default [
 
 </details>
 
+## no-upsert
+
+disallow proposal ES2026 [Upsert](https://github.com/tc39/proposal-upsert)\
+⚠️ This config will be changed in the minor versions of this plugin.
+
+This config includes the rules [es-x/no-map-prototype-getorinsert](../rules/no-map-prototype-getorinsert.md), [es-x/no-map-prototype-getorinsertcomputed](../rules/no-map-prototype-getorinsertcomputed.md), [es-x/no-weakmap-prototype-getorinsert](../rules/no-weakmap-prototype-getorinsert.md), and [es-x/no-weakmap-prototype-getorinsertcomputed](../rules/no-weakmap-prototype-getorinsertcomputed.md).
+
+```js
+import pluginESx from "eslint-plugin-es-x"
+export default [
+    pluginESx.configs['flat/no-upsert']
+]
+```
+
+<details><summary> Legacy Config </summary>
+
+.eslintrc.*:
+
+```json
+{
+    "extends": ["plugin:es-x/no-upsert"],
+}
+```
+
+</details>
+
 ## no-float16array
 
 disallow proposal ES2025 [Float16Array](https://github.com/tc39/proposal-float16array)
 
-This configs includes rules for [es-x/no-dataview-prototype-getfloat16-setfloat16](../rules/no-dataview-prototype-getfloat16-setfloat16.md), [es-x/no-float16array](../rules/no-float16array.md), and [es-x/no-math-f16round](../rules/no-math-f16round.md).
+This config includes the rules [es-x/no-dataview-prototype-getfloat16-setfloat16](../rules/no-dataview-prototype-getfloat16-setfloat16.md), [es-x/no-float16array](../rules/no-float16array.md), and [es-x/no-math-f16round](../rules/no-math-f16round.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1172,7 +1198,7 @@ export default [
 
 disallow proposal ES2025 [Import Attributes](https://github.com/tc39/proposal-import-attributes)
 
-This configs includes rules for [es-x/no-dynamic-import-options](../rules/no-dynamic-import-options.md), [es-x/no-import-attributes](../rules/no-import-attributes.md), and [es-x/no-trailing-dynamic-import-commas](../rules/no-trailing-dynamic-import-commas.md).
+This config includes the rules [es-x/no-dynamic-import-options](../rules/no-dynamic-import-options.md), [es-x/no-import-attributes](../rules/no-import-attributes.md), and [es-x/no-trailing-dynamic-import-commas](../rules/no-trailing-dynamic-import-commas.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1197,7 +1223,7 @@ export default [
 
 disallow proposal ES2025 [Iterator Helpers](https://github.com/tc39/proposal-iterator-helpers)
 
-This configs includes rules for [es-x/no-iterator-prototype-drop](../rules/no-iterator-prototype-drop.md), [es-x/no-iterator-prototype-every](../rules/no-iterator-prototype-every.md), [es-x/no-iterator-prototype-filter](../rules/no-iterator-prototype-filter.md), [es-x/no-iterator-prototype-find](../rules/no-iterator-prototype-find.md), [es-x/no-iterator-prototype-flatmap](../rules/no-iterator-prototype-flatmap.md), [es-x/no-iterator-prototype-foreach](../rules/no-iterator-prototype-foreach.md), [es-x/no-iterator-prototype-map](../rules/no-iterator-prototype-map.md), [es-x/no-iterator-prototype-reduce](../rules/no-iterator-prototype-reduce.md), [es-x/no-iterator-prototype-some](../rules/no-iterator-prototype-some.md), [es-x/no-iterator-prototype-take](../rules/no-iterator-prototype-take.md), [es-x/no-iterator-prototype-toarray](../rules/no-iterator-prototype-toarray.md), and [es-x/no-iterator](../rules/no-iterator.md).
+This config includes the rules [es-x/no-iterator-prototype-drop](../rules/no-iterator-prototype-drop.md), [es-x/no-iterator-prototype-every](../rules/no-iterator-prototype-every.md), [es-x/no-iterator-prototype-filter](../rules/no-iterator-prototype-filter.md), [es-x/no-iterator-prototype-find](../rules/no-iterator-prototype-find.md), [es-x/no-iterator-prototype-flatmap](../rules/no-iterator-prototype-flatmap.md), [es-x/no-iterator-prototype-foreach](../rules/no-iterator-prototype-foreach.md), [es-x/no-iterator-prototype-map](../rules/no-iterator-prototype-map.md), [es-x/no-iterator-prototype-reduce](../rules/no-iterator-prototype-reduce.md), [es-x/no-iterator-prototype-some](../rules/no-iterator-prototype-some.md), [es-x/no-iterator-prototype-take](../rules/no-iterator-prototype-take.md), [es-x/no-iterator-prototype-toarray](../rules/no-iterator-prototype-toarray.md), and [es-x/no-iterator](../rules/no-iterator.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1222,7 +1248,7 @@ export default [
 
 disallow proposal ES2025 [Set Methods for JavaScript](https://github.com/tc39/proposal-set-methods)
 
-This configs includes rules for [es-x/no-set-prototype-difference](../rules/no-set-prototype-difference.md), [es-x/no-set-prototype-intersection](../rules/no-set-prototype-intersection.md), [es-x/no-set-prototype-isdisjointfrom](../rules/no-set-prototype-isdisjointfrom.md), [es-x/no-set-prototype-issubsetof](../rules/no-set-prototype-issubsetof.md), [es-x/no-set-prototype-issupersetof](../rules/no-set-prototype-issupersetof.md), [es-x/no-set-prototype-symmetricdifference](../rules/no-set-prototype-symmetricdifference.md), and [es-x/no-set-prototype-union](../rules/no-set-prototype-union.md).
+This config includes the rules [es-x/no-set-prototype-difference](../rules/no-set-prototype-difference.md), [es-x/no-set-prototype-intersection](../rules/no-set-prototype-intersection.md), [es-x/no-set-prototype-isdisjointfrom](../rules/no-set-prototype-isdisjointfrom.md), [es-x/no-set-prototype-issubsetof](../rules/no-set-prototype-issubsetof.md), [es-x/no-set-prototype-issupersetof](../rules/no-set-prototype-issupersetof.md), [es-x/no-set-prototype-symmetricdifference](../rules/no-set-prototype-symmetricdifference.md), and [es-x/no-set-prototype-union](../rules/no-set-prototype-union.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1247,7 +1273,7 @@ export default [
 
 disallow proposal ES2024 [Array Grouping](https://github.com/tc39/proposal-array-grouping)
 
-This configs includes rules for [es-x/no-map-groupby](../rules/no-map-groupby.md) and [es-x/no-object-groupby](../rules/no-object-groupby.md).
+This config includes the rules [es-x/no-map-groupby](../rules/no-map-groupby.md) and [es-x/no-object-groupby](../rules/no-object-groupby.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1272,7 +1298,7 @@ export default [
 
 disallow proposal ES2024 [Well-Formed Unicode Strings](https://github.com/tc39/proposal-is-usv-string)
 
-This configs includes rules for [es-x/no-string-prototype-iswellformed](../rules/no-string-prototype-iswellformed.md) and [es-x/no-string-prototype-towellformed](../rules/no-string-prototype-towellformed.md).
+This config includes the rules [es-x/no-string-prototype-iswellformed](../rules/no-string-prototype-iswellformed.md) and [es-x/no-string-prototype-towellformed](../rules/no-string-prototype-towellformed.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1297,7 +1323,7 @@ export default [
 
 disallow proposal ES2023 [Change Array by Copy](https://github.com/tc39/proposal-change-array-by-copy)
 
-This configs includes rules for [es-x/no-array-prototype-toreversed](../rules/no-array-prototype-toreversed.md), [es-x/no-array-prototype-tosorted](../rules/no-array-prototype-tosorted.md), [es-x/no-array-prototype-tospliced](../rules/no-array-prototype-tospliced.md), and [es-x/no-array-prototype-with](../rules/no-array-prototype-with.md).
+This config includes the rules [es-x/no-array-prototype-toreversed](../rules/no-array-prototype-toreversed.md), [es-x/no-array-prototype-tosorted](../rules/no-array-prototype-tosorted.md), [es-x/no-array-prototype-tospliced](../rules/no-array-prototype-tospliced.md), and [es-x/no-array-prototype-with](../rules/no-array-prototype-with.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1322,7 +1348,7 @@ export default [
 
 disallow proposal ES2023 Intl API [Intl.NumberFormat V3](https://github.com/tc39/proposal-intl-numberformat-v3)
 
-This configs includes rules for [es-x/no-intl-numberformat-prototype-formatrange](../rules/no-intl-numberformat-prototype-formatrange.md), [es-x/no-intl-numberformat-prototype-formatrangetoparts](../rules/no-intl-numberformat-prototype-formatrangetoparts.md), and [es-x/no-intl-pluralrules-prototype-selectrange](../rules/no-intl-pluralrules-prototype-selectrange.md).
+This config includes the rules [es-x/no-intl-numberformat-prototype-formatrange](../rules/no-intl-numberformat-prototype-formatrange.md), [es-x/no-intl-numberformat-prototype-formatrangetoparts](../rules/no-intl-numberformat-prototype-formatrangetoparts.md), and [es-x/no-intl-pluralrules-prototype-selectrange](../rules/no-intl-pluralrules-prototype-selectrange.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1347,7 +1373,7 @@ export default [
 
 disallow proposal ES2022 [Class Fields](https://github.com/tc39/proposal-class-fields)
 
-This configs includes rules for [es-x/no-class-instance-fields](../rules/no-class-instance-fields.md), [es-x/no-class-private-fields](../rules/no-class-private-fields.md), [es-x/no-class-private-methods](../rules/no-class-private-methods.md), and [es-x/no-class-static-fields](../rules/no-class-static-fields.md).
+This config includes the rules [es-x/no-class-instance-fields](../rules/no-class-instance-fields.md), [es-x/no-class-private-fields](../rules/no-class-private-fields.md), [es-x/no-class-private-methods](../rules/no-class-private-methods.md), and [es-x/no-class-static-fields](../rules/no-class-static-fields.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1372,7 +1398,7 @@ export default [
 
 disallow proposal ES2022 [An .at() method on all the built-in indexables](https://github.com/tc39/proposal-relative-indexing-method)
 
-This configs includes rules for [es-x/no-array-prototype-at](../rules/no-array-prototype-at.md) and [es-x/no-string-prototype-at](../rules/no-string-prototype-at.md).
+This config includes the rules [es-x/no-array-prototype-at](../rules/no-array-prototype-at.md) and [es-x/no-string-prototype-at](../rules/no-string-prototype-at.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"
@@ -1397,7 +1423,7 @@ export default [
 
 disallow proposal ES2020 [String.prototype.matchAll](https://github.com/tc39/proposal-string-matchall)
 
-This configs includes rules for [es-x/no-string-prototype-matchall](../rules/no-string-prototype-matchall.md) and [es-x/no-symbol-matchall](../rules/no-symbol-matchall.md).
+This config includes the rules [es-x/no-string-prototype-matchall](../rules/no-string-prototype-matchall.md) and [es-x/no-symbol-matchall](../rules/no-symbol-matchall.md).
 
 ```js
 import pluginESx from "eslint-plugin-es-x"

docs/rules/index.md

@@ -18,6 +18,8 @@ There is a config that enables the rules in this category: [`no-new-in-esnext`]
 | [es-x/no-json-israwjson](./no-json-israwjson.md) | disallow the `JSON.isRawJSON` method. |  |
 | [es-x/no-json-parse-reviver-context-parameter](./no-json-parse-reviver-context-parameter.md) | disallow the `context` parameter in `JSON.parse` reviver function. |  |
 | [es-x/no-json-rawjson](./no-json-rawjson.md) | disallow the `JSON.rawJSON` method. |  |
+| [es-x/no-map-prototype-getorinsert](./no-map-prototype-getorinsert.md) | disallow the `Map.prototype.getOrInsert` method. |  |
+| [es-x/no-map-prototype-getorinsertcomputed](./no-map-prototype-getorinsertcomputed.md) | disallow the `Map.prototype.getOrInsertComputed` method. |  |
 | [es-x/no-math-sumprecise](./no-math-sumprecise.md) | disallow the `Math.sumPrecise` method. |  |
 | [es-x/no-suppressederror](./no-suppressederror.md) | disallow the `SuppressedError` class. |  |
 | [es-x/no-symbol-asyncdispose](./no-symbol-asyncdispose.md) | disallow the `Symbol.asyncDispose` property. |  |
@@ -29,6 +31,8 @@ There is a config that enables the rules in this category: [`no-new-in-esnext`]
 | [es-x/no-uint8array-prototype-tobase64](./no-uint8array-prototype-tobase64.md) | disallow the `Uint8Array.prototype.toBase64` method. |  |
 | [es-x/no-uint8array-prototype-tohex](./no-uint8array-prototype-tohex.md) | disallow the `Uint8Array.prototype.toHex` method. |  |
 | [es-x/no-using-declarations](./no-using-declarations.md) | disallow `using` and `await using` declarations. |  |
+| [es-x/no-weakmap-prototype-getorinsert](./no-weakmap-prototype-getorinsert.md) | disallow the `WeakMap.prototype.getOrInsert` method. |  |
+| [es-x/no-weakmap-prototype-getorinsertcomputed](./no-weakmap-prototype-getorinsertcomputed.md) | disallow the `WeakMap.prototype.getOrInsertComputed` method. |  |
 
 ## ES2026 Intl API
 

docs/rules/no-map-prototype-getorinsert.md

@@ -0,0 +1,62 @@
+---
+title: "es-x/no-map-prototype-getorinsert"
+description: "disallow the `Map.prototype.getOrInsert` method"
+---
+
+# es-x/no-map-prototype-getorinsert
+> disallow the `Map.prototype.getOrInsert` method
+
+- ❗ <badge text="This rule has not been released yet." vertical="middle" type="error"> ***This rule has not been released yet.*** </badge>
+- ✅ The following configurations enable this rule: [no-new-in-esnext] and [no-upsert]
+
+This rule reports ES2026 [`Map.prototype.getOrInsert` method](https://github.com/tc39/proposal-upsert) as errors.
+
+## 💡 Examples
+
+⛔ Examples of **incorrect** code for this rule:
+
+<eslint-playground type="bad">
+
+```js
+/*eslint es-x/no-map-prototype-getorinsert: error */
+const foo = new Map();
+foo.getOrInsert(key, value);
+```
+
+</eslint-playground>
+
+## 🔧 Options
+
+This rule has an option.
+
+```jsonc
+{
+  "rules": {
+    "es-x/no-map-prototype-getorinsert": [
+      "error",
+      {
+        "aggressive": false,
+        "allowTestedProperty": false
+      }
+    ]
+  }
+}
+```
+
+### aggressive: boolean
+
+Configure the aggressive mode for only this rule.
+This is prior to the `settings['es-x'].aggressive` setting.
+
+### allowTestedProperty: boolean
+
+Configure the allowTestedProperty mode for only this rule.
+This is prior to the `settings['es-x'].allowTestedProperty` setting.
+
+## 📚 References
+
+- [Rule source](https://github.com/eslint-community/eslint-plugin-es-x/blob/master/lib/rules/no-map-prototype-getorinsert.js)
+- [Test source](https://github.com/eslint-community/eslint-plugin-es-x/blob/master/tests/lib/rules/no-map-prototype-getorinsert.js)
+
+[no-new-in-esnext]: ../configs/index.md#no-new-in-esnext
+[no-upsert]: ../configs/index.md#no-upsert