angular-eslint · JamesHenry · Nov 9, 2025 · Nov 9, 2025
diff --git a/package.json b/package.json
@@ -57,6 +57,7 @@
     "@angular/compiler": "catalog:",
     "@commitlint/cli": "catalog:",
     "@commitlint/config-conventional": "catalog:",
+    "@eslint/core": "catalog:",
     "@mdn/browser-compat-data": "catalog:",
     "@nx/devkit": "catalog:",
     "@nx/esbuild": "catalog:",

diff --git a/packages/angular-eslint/src/index.ts b/packages/angular-eslint/src/index.ts
@@ -1,6 +1,7 @@
 import tsPluginBase from '@angular-eslint/eslint-plugin';
 import templatePluginBase from '@angular-eslint/eslint-plugin-template';
 import * as templateParserBase from '@angular-eslint/template-parser';
+import type { Plugin as ESLintPlugin } from '@eslint/core';
 import type { TSESLint } from '@typescript-eslint/utils';
 import { parser } from 'typescript-eslint';
 
@@ -16,7 +17,9 @@ const templateParser: TSESLint.FlatConfig.Parser = {
 };
 
 /*
-we could build a plugin object here without the `configs` key - but if we do
+NOTE: Comment and approach taken from typescript-eslint:
+
+We could build a plugin object here without the `configs` key - but if we do
 that then we create a situation in which
 ```
 require('angular-eslint').tsPlugin !== require('@angular-eslint/eslint-plugin')
@@ -38,14 +41,18 @@ use our new package); however legacy configs consumed via `@eslint/eslintrc`
 would never be able to satisfy this constraint and thus users would be blocked
 from using them.
 */
-const tsPlugin: TSESLint.FlatConfig.Plugin = tsPluginBase as Omit<
-  typeof tsPluginBase,
-  'configs'
->;
-const templatePlugin: TSESLint.FlatConfig.Plugin = templatePluginBase as Omit<
-  typeof templatePluginBase,
-  'configs'
->;
+
+/**
+ * Make the plugins compatible with both ESLint's Plugin type and typescript-eslint's
+ * FlatConfig.Plugin type through type assertion.
+ *
+ * This is covered by a type compatibility test in tests/type-compatibility.test.ts
+ */
+type CompatiblePlugin = Omit<ESLintPlugin, 'configs'> & {
+  configs?: never;
+};
+const tsPlugin = tsPluginBase as unknown as CompatiblePlugin;
+const templatePlugin = templatePluginBase as unknown as CompatiblePlugin;
 
 const configs = {
   tsAll: tsAllConfig(tsPlugin, parser),

diff --git a/packages/angular-eslint/tests/type-compatibility.test.ts b/packages/angular-eslint/tests/type-compatibility.test.ts
@@ -0,0 +1,64 @@
+/**
+ * This test file exists purely to be type-checked in CI to ensure that angular-eslint plugins and parsers are compatible with both:
+ * 1. ESLint's defineConfig function (uses ESLint.Plugin and Linter.ParserModule types)
+ * 2. typescript-eslint's config function (uses TSESLint.FlatConfig.Plugin and TSESLint.FlatConfig.Parser types)
+ */
+
+import { defineConfig } from 'eslint/config';
+import { config } from 'typescript-eslint';
+
+import angular from '../src/index';
+
+/**
+ * Test 1: Verify compatibility with ESLint's defineConfig
+ */
+defineConfig([
+  {
+    files: ['**/*.ts'],
+    plugins: {
+      '@angular-eslint': angular.tsPlugin,
+    },
+    rules: {
+      '@angular-eslint/component-class-suffix': 'error',
+    },
+  },
+  {
+    files: ['**/*.html'],
+    plugins: {
+      '@angular-eslint/template': angular.templatePlugin,
+    },
+    languageOptions: {
+      parser: angular.templateParser,
+    },
+    rules: {
+      '@angular-eslint/template/banana-in-box': 'error',
+    },
+  },
+]);
+
+/**
+ * Test 2: Verify compatibility with typescript-eslint's config function
+ */
+config(
+  {
+    files: ['**/*.ts'],
+    plugins: {
+      '@angular-eslint': angular.tsPlugin,
+    },
+    rules: {
+      '@angular-eslint/component-class-suffix': 'error',
+    },
+  },
+  {
+    files: ['**/*.html'],
+    plugins: {
+      '@angular-eslint/template': angular.templatePlugin,
+    },
+    languageOptions: {
+      parser: angular.templateParser,
+    },
+    rules: {
+      '@angular-eslint/template/banana-in-box': 'error',
+    },
+  },
+);
diff --git a/packages/angular-eslint/tsconfig.json b/packages/angular-eslint/tsconfig.json
@@ -22,6 +22,9 @@
     },
     {
       "path": "./tsconfig.lib.json"
+    },
+    {
+      "path": "./tsconfig.type-compat.json"
     }
   ]
 }
diff --git a/packages/angular-eslint/tsconfig.type-compat.json b/packages/angular-eslint/tsconfig.type-compat.json
@@ -0,0 +1,15 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "../../dist/out-tsc/angular-eslint-type-compat",
+    "types": ["node"],
+    "sourceMap": true,
+    "skipLibCheck": false
+  },
+  "include": ["tests/type-compatibility.test.ts"],
+  "references": [
+    {
+      "path": "./tsconfig.lib.json"
+    }
+  ]
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
@@ -6,6 +6,7 @@ catalog:
   '@angular/compiler': 20.3.9
   '@commitlint/cli': 20.1.0
   '@commitlint/config-conventional': 20.0.0
+  '@eslint/core': ^0.17.0
   '@mdn/browser-compat-data': 7.1.18
   '@nx/devkit': 22.1.0-beta.3
   '@nx/esbuild': 22.1.0-beta.3
-Original file line number
+Diff line change
@@ Expand Up / @@ -22,6 +22,9 @@ @@
         },
         {
           "path": "./tsconfig.lib.json"
+        },
+        {
+          "path": "./tsconfig.type-compat.json"
         }
       ]
     }