feat: add support for flat config (#139)

* feat: add support for flat config

* Create rare-grapes-call.md

* fix

.changeset/rare-grapes-call.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-node-dependencies": minor
+---
+
+feat: add support for flat config

.eslintignore

@@ -6,6 +6,7 @@
 !/.vscode
 !/.github
 /tests/fixtures/integrations/eslint-plugin
+/tests/fixtures/integrations/eslint-plugin-legacy-config
 !/docs/.vitepress
 /docs/.vitepress/dist
 /docs/.vitepress/cache

.github/workflows/NodeCI.yml

@@ -30,7 +30,9 @@ jobs:
         with:
           node-version: ${{ matrix.node-version }}
       - name: Install Packages
-        run: npm i --legacy-peer-deps
+        run: npm i -f
+      - name: Build
+        run: npm run build
       - name: Test
         run: npm test
   test-with-eslint9:
@@ -43,6 +45,8 @@ jobs:
           npm i -D eslint@^9.0.0-0 -f
           npx rimraf node_modules
           npm install -f
+      - name: Build
+        run: npm run build
       - name: Test
         run: npm test
   test-with-eslint6:
@@ -57,6 +61,8 @@ jobs:
           npm i -D eslint@6
           npx rimraf node_modules
           npm install
+      - name: Build
+        run: npm run build
       - name: Test
         run: npm test
   test-and-coverage:
@@ -65,7 +71,9 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
       - name: Install Packages
-        run: npm i --legacy-peer-deps
+        run: npm i -f
+      - name: Build
+        run: npm run build
       - name: Test
         run: npm run test:nyc
       - name: Coveralls GitHub Action
@@ -78,7 +86,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-node@v4
       - name: Install Packages
-        run: npm i --legacy-peer-deps
+        run: npm i -f
       - name: Build
         run: npm run build
       - name: Update

README.md

@@ -41,13 +41,27 @@ npm install --save-dev eslint eslint-plugin-node-dependencies
 
 <!--USAGE_SECTION_START-->
 
-Add `node-dependencies` to the plugins section of your `.eslintrc` configuration file (you can omit the `eslint-plugin-` prefix)  
+Add `node-dependencies` to the plugins section of your `eslint.config.js` or `.eslintrc` configuration file (you can omit the `eslint-plugin-` prefix)  
 and either use one of the two configurations available (`recommended`) or configure the rules you want:
 
-### The recommended configuration
+### The recommended configuration (New Config)
+
+The `plugin.configs["flat/recommended"]` config enables a subset of [the rules](#white_check_mark-rules) that should be most useful to most users.
+*See [lib/configs/rules/recommended.ts](https://github.com/ota-meshi/eslint-plugin-node-dependencies/blob/main/lib/configs/rules/recommended.ts) for more details.*
+
+```js
+// eslint.config.js
+import * as nodeDependenciesPlugin from "eslint-plugin-node-dependencies"
+
+export default [
+    ...nodeDependenciesPlugin.configs["flat/recommended"],
+];
+```
+
+### The recommended configuration (Legacy Config)
 
 The `plugin:node-dependencies/recommended` config enables a subset of [the rules](#white_check_mark-rules) that should be most useful to most users.
-*See [lib/configs/recommended.ts](https://github.com/ota-meshi/eslint-plugin-node-dependencies/blob/main/lib/configs/recommended.ts) for more details.*
+*See [lib/configs/rules/recommended.ts](https://github.com/ota-meshi/eslint-plugin-node-dependencies/blob/main/lib/configs/rules/recommended.ts) for more details.*
 
 ```js
 // .eslintrc.js
@@ -67,6 +81,21 @@ module.exports = {
 
 Override/add specific rules configurations. *See also: [http://eslint.org/docs/user-guide/configuring](http://eslint.org/docs/user-guide/configuring)*.
 
+```js
+// eslint.config.js
+import * as nodeDependenciesPlugin from "eslint-plugin-node-dependencies"
+
+export default [
+    {
+        plugins: { "node-dependencies": nodeDependenciesPlugin }
+        rules: {
+            // Override/add rules settings here, such as:
+            "node-dependencies/rule-name": "error"
+        }
+    }
+];
+```
+
 ```js
 // .eslintrc.js
 module.exports = {

docs/user-guide/index.md

@@ -17,13 +17,27 @@ npm install --save-dev eslint eslint-plugin-node-dependencies
 
 <!--USAGE_SECTION_START-->
 
-Add `node-dependencies` to the plugins section of your `.eslintrc` configuration file (you can omit the `eslint-plugin-` prefix)  
+Add `node-dependencies` to the plugins section of your `eslint.config.js` or `.eslintrc` configuration file (you can omit the `eslint-plugin-` prefix)  
 and either use one of the two configurations available (`recommended`) or configure the rules you want:
 
-### The recommended configuration
+### The recommended configuration (New Config)
+
+The `plugin.configs["flat/recommended"]` config enables a subset of [the rules](../rules/index.md) that should be most useful to most users.
+*See [lib/configs/rules/recommended.ts](https://github.com/ota-meshi/eslint-plugin-node-dependencies/blob/main/lib/configs/rules/recommended.ts) for more details.*
+
+```js
+// eslint.config.js
+import * as nodeDependenciesPlugin from "eslint-plugin-node-dependencies"
+
+export default [
+    ...nodeDependenciesPlugin.configs["flat/recommended"],
+];
+```
+
+### The recommended configuration (Legacy Config)
 
 The `plugin:node-dependencies/recommended` config enables a subset of [the rules](../rules/index.md) that should be most useful to most users.
-*See [lib/configs/recommended.ts](https://github.com/ota-meshi/eslint-plugin-node-dependencies/blob/main/lib/configs/recommended.ts) for more details.*
+*See [lib/configs/rules/recommended.ts](https://github.com/ota-meshi/eslint-plugin-node-dependencies/blob/main/lib/configs/rules/recommended.ts) for more details.*
 
 ```js
 // .eslintrc.js
@@ -43,6 +57,21 @@ module.exports = {
 
 Override/add specific rules configurations. *See also: [http://eslint.org/docs/user-guide/configuring](http://eslint.org/docs/user-guide/configuring)*.
 
+```js
+// eslint.config.js
+import * as nodeDependenciesPlugin from "eslint-plugin-node-dependencies"
+
+export default [
+    {
+        plugins: { "node-dependencies": nodeDependenciesPlugin }
+        rules: {
+            // Override/add rules settings here, such as:
+            "node-dependencies/rule-name": "error"
+        }
+    }
+];
+```
+
 ```js
 // .eslintrc.js
 module.exports = {

lib/configs/flat/recommended.ts

@@ -0,0 +1,21 @@
+import type { ESLint, Linter } from "eslint";
+import recommendedRules from "../rules/recommended";
+import * as jsonParser from "jsonc-eslint-parser";
+export const recommendedConfig = [
+  {
+    plugins: {
+      // eslint-disable-next-line @typescript-eslint/naming-convention -- ignore
+      get "node-dependencies"(): ESLint.Plugin {
+        // eslint-disable-next-line @typescript-eslint/no-require-imports -- ignore
+        return require("../../index");
+      },
+    },
+  },
+  {
+    files: ["**/package.json", "package.json"],
+    languageOptions: {
+      parser: jsonParser,
+    },
+    rules: recommendedRules.rules,
+  },
+] satisfies Linter.FlatConfig[];

lib/configs/recommended.ts

@@ -1,3 +1,4 @@
+import recommendedRules from "./rules/recommended";
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment -- ignore
 // @ts-ignore -- Backwards compatibility
 export = {
@@ -6,12 +7,7 @@ export = {
     {
       files: ["package.json"],
       parser: require.resolve("jsonc-eslint-parser"),
-      rules: {
-        // eslint-plugin-node-dependencies rules
-        "node-dependencies/compat-engines": "error",
-        "node-dependencies/no-dupe-deps": "error",
-        "node-dependencies/valid-semver": "error",
-      },
+      rules: recommendedRules.rules,
     },
   ],
 };

lib/configs/rules/recommended.ts

@@ -0,0 +1,10 @@
+import type { Linter } from "eslint";
+
+export default {
+  rules: {
+    // eslint-plugin-node-dependencies rules
+    "node-dependencies/compat-engines": "error",
+    "node-dependencies/no-dupe-deps": "error",
+    "node-dependencies/valid-semver": "error",
+  } as Linter.RulesRecord,
+};

lib/index.ts

@@ -1,10 +1,12 @@
 import type { RuleModule } from "./types";
 import { rules as ruleList } from "./utils/rules";
 import recommended from "./configs/recommended";
+import { recommendedConfig as flatRecommended } from "./configs/flat/recommended";
 import * as meta from "./meta";
 
 const configs = {
   recommended,
+  "flat/recommended": flatRecommended,
 };
 
 const rules = ruleList.reduce(

package.json

@@ -16,7 +16,7 @@
     "lint": "eslint . --ext .js,.vue,.ts,.json,.yaml,.yml",
     "eslint-fix": "eslint . --ext .js,.vue,.ts,.json,.yaml,.yml --fix",
     "pretest": "npm run build",
-    "test:base": "mocha --require ts-node/register \"tests/**/*.ts\" --reporter dot --timeout 60000",
+    "test:base": "mocha --require ts-node/register/transpile-only \"tests/**/*.ts\" --reporter dot --timeout 60000",
     "test": "npm run test:nyc",
     "test:nyc": "nyc --reporter=lcov npm run test:base",
     "test:debug": "mocha --require ts-node/register/transpile-only \"tests/**/*.ts\" --reporter dot --timeout 60000",

tests/fixtures/integrations/eslint-plugin-legacy-config/package.json

@@ -0,0 +1,8 @@
+{
+  "engines": {
+    "node": ">=8"
+  },
+  "dependencies": {
+    "semver": "^7.3.5"
+  }
+}

tests/fixtures/integrations/eslint-plugin/eslint.config.mjs

@@ -0,0 +1,5 @@
+import * as nodeDependenciesPlugin from "../../../../dist/index.js"
+
+export default [
+    ...nodeDependenciesPlugin.configs["flat/recommended"],
+];

tests/lib/eslint-plugin.ts

@@ -1,33 +1,66 @@
 import path from "path";
 import assert from "assert";
 import { getLegacyESLint } from "eslint-compat-utils/eslint";
+import * as eslintModule from "eslint";
 import plugin from "../../lib/index";
-// eslint-disable-next-line @typescript-eslint/naming-convention -- ignore
-const ESLint = getLegacyESLint();
 
 // -----------------------------------------------------------------------------
 // Tests
 // -----------------------------------------------------------------------------
 
-const TEST_CWD = path.join(__dirname, "../fixtures/integrations/eslint-plugin");
+const TEST_CWD_FOR_FLAT_CONFIG = path.join(
+  __dirname,
+  "../fixtures/integrations/eslint-plugin",
+);
+const TEST_CWD_FOR_LEGACY_CONFIG = path.join(
+  __dirname,
+  "../fixtures/integrations/eslint-plugin-legacy-config",
+);
 
-describe("Integration with eslint-plugin-node-dependencies", () => {
-  if (!ESLint) {
-    return;
-  }
-  it("should lint without errors", async () => {
-    const engine = new ESLint({
-      cwd: TEST_CWD,
-      plugins: {
-        "eslint-plugin-node-dependencies": plugin as never,
-      },
+describe("Integration with eslint-plugin-node-dependencies", async () => {
+  // eslint-disable-next-line @typescript-eslint/naming-convention -- ignore
+  const FlatESLint: typeof eslintModule.ESLint =
+    // @ts-expect-error -- new API
+    typeof eslintModule.loadESLint === "function"
+      ? // @ts-expect-error -- new API
+        await eslintModule.loadESLint({ useFlatConfig: true })
+      : null;
+  // eslint-disable-next-line @typescript-eslint/naming-convention -- ignore
+  const ESLint: typeof eslintModule.ESLint =
+    // @ts-expect-error -- new API
+    typeof eslintModule.loadESLint === "function"
+      ? // @ts-expect-error -- new API
+        await eslintModule.loadESLint({ useFlatConfig: false })
+      : getLegacyESLint();
+  if (FlatESLint) {
+    it("should lint without errors (with flat config)", async () => {
+      const eslint = new FlatESLint({
+        cwd: TEST_CWD_FOR_FLAT_CONFIG,
+      });
+      const results = await eslint.lintFiles(["package.json"]);
+
+      assert.strictEqual(results.length, 1);
+      assert.deepStrictEqual(
+        results[0].messages.map((m) => m.ruleId),
+        ["node-dependencies/compat-engines"],
+      );
     });
-    const results = await engine.lintFiles(["package.json"]);
+  }
+  if (ESLint) {
+    it("should lint without errors (with legacy config)", async () => {
+      const engine = new ESLint({
+        cwd: TEST_CWD_FOR_LEGACY_CONFIG,
+        plugins: {
+          "eslint-plugin-node-dependencies": plugin as never,
+        },
+      });
+      const results = await engine.lintFiles(["package.json"]);
 
-    assert.strictEqual(results.length, 1);
-    assert.deepStrictEqual(
-      results[0].messages.map((m) => m.ruleId),
-      ["node-dependencies/compat-engines"],
-    );
-  });
+      assert.strictEqual(results.length, 1);
+      assert.deepStrictEqual(
+        results[0].messages.map((m) => m.ruleId),
+        ["node-dependencies/compat-engines"],
+      );
+    });
+  }
 });

tools/update-rulesets.ts

@@ -3,34 +3,23 @@ import fs from "fs";
 // import eslint from "eslint"
 import { rules } from "./lib/load-rules";
 
-const content = `
-// eslint-disable-next-line @typescript-eslint/ban-ts-comment -- ignore
-// @ts-ignore -- Backwards compatibility
-export = {
-    plugins: ["node-dependencies"],
-    overrides: [
-        {
-            files: ["package.json"],
-            parser: require.resolve("jsonc-eslint-parser"),
-            rules: {
-                // eslint-plugin-node-dependencies rules
-                ${rules
-                  .filter(
-                    (rule) =>
-                      rule.meta.docs.recommended && !rule.meta.deprecated,
-                  )
-                  .map((rule) => {
-                    const conf = rule.meta.docs.default || "error";
-                    return `"${rule.meta.docs.ruleId}": "${conf}"`;
-                  })
-                  .join(",\n")}
-            }
-        }
-    ]
+const content = `import type { Linter } from "eslint";
+
+export default {
+    rules: {
+        // eslint-plugin-node-dependencies rules
+        ${rules
+          .filter((rule) => rule.meta.docs.recommended && !rule.meta.deprecated)
+          .map((rule) => {
+            const conf = rule.meta.docs.default || "error";
+            return `"${rule.meta.docs.ruleId}": "${conf}"`;
+          })
+          .join(",\n")}
+    } as Linter.RulesRecord
 }
 `;
 
-const filePath = path.resolve(__dirname, "../lib/configs/recommended.ts");
+const filePath = path.resolve(__dirname, "../lib/configs/rules/recommended.ts");
 
 // Update file.
 fs.writeFileSync(filePath, content);