Add oxlint complexity rule

README.md

@@ -44,7 +44,7 @@ gh get timobechtel/style templates/.oxfmtrc.json
 > Faster ESLint alternative. 5x faster in personal testing.
 
 ```bash
-npm i -D oxlint
+npm i -D oxlint @oxlint/plugins oxlint-plugin-complexity
 ```
 
 Core:
@@ -54,6 +54,7 @@ gh get timobechtel/style templates/.oxlintrc.jsonc
 ```
 
 - [oxlint core template](https://github.com/TimoBechtel/style/blob/main/templates/.oxlintrc.jsonc)
+- Includes the `oxlint-plugin-complexity` rule with sensible defaults (`cyclomatic: 20`, `cognitive: 15`, `minLines: 15`) to catch overly complex functions without flagging short helpers.
 
 React:
 
@@ -62,23 +63,24 @@ gh get timobechtel/style templates/react/.oxlintrc.jsonc
 ```
 
 - [oxlint react template](https://github.com/TimoBechtel/style/blob/main/templates/react/.oxlintrc.jsonc)
+- React projects inherit the same complexity checks from the shared core config.
 
 <details>
   <summary>Migrating to Oxlint? - `File '@timobechtel/style/tsconfig/core' not found.`</summary>
 
-  When migrating from ESLint to Oxlint, you might need to update the `tsconfig.json` file:
+When migrating from ESLint to Oxlint, you might need to update the `tsconfig.json` file:
 
-  ```diff
-  - "extends": ["@timobechtel/style/tsconfig/core"]
-  + "extends": ["@timobechtel/style/tsconfig/core.json"]
-  ```
+```diff
+- "extends": ["@timobechtel/style/tsconfig/core"]
++ "extends": ["@timobechtel/style/tsconfig/core.json"]
+```
 
-  ```diff
-  - "extends": ["@timobechtel/style/tsconfig/react"]
-  + "extends": ["@timobechtel/style/tsconfig/react.json"]
-  ```
+```diff
+- "extends": ["@timobechtel/style/tsconfig/react"]
++ "extends": ["@timobechtel/style/tsconfig/react.json"]
+```
 
-  > tsgolint requires a file extension to resolve the config file.
+> tsgolint requires a file extension to resolve the config file.
 
 </details>
 

oxlint/core.jsonc

@@ -6,6 +6,9 @@
     "oxc",
     "import"
   ],
+  "jsPlugins": [
+    "oxlint-plugin-complexity"
+  ],
   "categories": {
     "correctness": "error",
     "suspicious": "error",
@@ -187,6 +190,14 @@
 
     // report duplicate code in branches
     "oxc/branches-sharing-code": "warn",
+    "complexity/complexity": [
+      "warn",
+      {
+        "cyclomatic": 20,
+        "cognitive": 15,
+        "minLines": 15
+      }
+    ],
     // prevent mixing value and non-value returns in functions
     "typescript/consistent-return": "warn",
     "typescript/no-unnecessary-qualifier": "warn",

package.json

@@ -22,15 +22,19 @@
     "semantic-release": "^25.0.3",
     "typescript": "^5.9.3",
     "oxlint": "^1.55.0",
-    "oxfmt": "^0.40.0"
+    "oxfmt": "^0.40.0",
+    "@oxlint/plugins": "^1.63.0",
+    "oxlint-plugin-complexity": "^2.1.2"
   },
   "peerDependencies": {
     "eslint": "^9.39.3",
     "prettier": "^3.8.1",
     "semantic-release": "^25.0.3",
     "typescript": "^5.9.3",
     "oxlint": "^1.55.0",
-    "oxfmt": "^0.40.0"
+    "oxfmt": "^0.40.0",
+    "@oxlint/plugins": "^1.63.0",
+    "oxlint-plugin-complexity": "^2.1.2"
   },
   "dependencies": {
     "@eslint/js": "^9.39.3",