feat: add support for flat config (#301)

* feat: add support for flat config

* fix

* Create rare-coats-report.md

* fix test

Author: ota-meshi

.changeset/rare-coats-report.md

@@ -0,0 +1,5 @@
+---
+"eslint-plugin-json-schema-validator": minor
+---
+
+feat: add support for flat config

.eslintrc.js

@@ -188,5 +188,17 @@ module.exports = {
         "eslint-plugin/require-meta-schema": "off",
       },
     },
+    {
+      files: ["*.mjs"],
+      parserOptions: {
+        sourceType: "module",
+      },
+    },
+    {
+      files: ["*.md/**", "**/*.md/**"],
+      rules: {
+        "n/no-missing-import": "off",
+      },
+    },
   ],
 };

README.md

@@ -43,7 +43,35 @@ npm install --save-dev eslint eslint-plugin-jsonc eslint-plugin-json-schema-vali
 
 ### Configuration
 
-Use `.eslintrc.*` file to configure rules. See also: [https://eslint.org/docs/user-guide/configuring](https://eslint.org/docs/user-guide/configuring).
+#### New (ESLint>=v9) Config (Flat Config)
+
+Use `eslint.config.js` file to configure rules. See also: <https://eslint.org/docs/latest/use/configure/configuration-files-new>.
+
+Example **eslint.config.js**:
+
+```mjs
+import eslintPluginJsonSchemaValidator from 'eslint-plugin-json-schema-validator';
+export default [
+  // add more generic rule sets here, such as:
+  // js.configs.recommended,
+  ...eslintPluginJsonSchemaValidator.configs['flat/recommended'],
+  {
+    rules: {
+      // override/add rules settings here, such as:
+      // 'json-schema-validator/no-invalid': 'warn'
+    }
+  }
+];
+```
+
+This plugin provides configs:
+
+- `*.configs['flat/base']` ... Configuration to enable correct JSON, YAML and TOML parsing.
+- `*.configs['flat/recommended']` ... Above, plus rule to validate with JSON Schema.
+
+#### Legacy Config (ESLint<v9)
+
+Use `.eslintrc.*` file to configure rules. See also: <https://eslint.org/docs/latest/use/configure/>.
 
 Example **.eslintrc.js**:
 

docs/user-guide/README.md

@@ -18,7 +18,35 @@ npm install --save-dev eslint eslint-plugin-json-schema-validator
 
 ### Configuration
 
-Use `.eslintrc.*` file to configure rules. See also: [https://eslint.org/docs/user-guide/configuring](https://eslint.org/docs/user-guide/configuring).
+#### New (ESLint>=v9) Config (Flat Config)
+
+Use `eslint.config.js` file to configure rules. See also: <https://eslint.org/docs/latest/use/configure/configuration-files-new>.
+
+Example **eslint.config.js**:
+
+```mjs
+import eslintPluginJsonSchemaValidator from 'eslint-plugin-json-schema-validator';
+export default [
+  // add more generic rule sets here, such as:
+  // js.configs.recommended,
+  ...eslintPluginJsonSchemaValidator.configs['flat/recommended'],
+  {
+    rules: {
+      // override/add rules settings here, such as:
+      // 'json-schema-validator/no-invalid': 'warn'
+    }
+  }
+];
+```
+
+This plugin provides configs:
+
+- `*.configs['flat/base']` ... Configuration to enable correct JSON, YAML and TOML parsing.
+- `*.configs['flat/recommended']` ... Above, plus rule to validate with JSON Schema.
+
+#### Legacy Config (ESLint<v9)
+
+Use `.eslintrc.*` file to configure rules. See also: <https://eslint.org/docs/latest/use/configure/>.
 
 Example **.eslintrc.js**:
 

src/configs/flat/base.ts

@@ -0,0 +1,57 @@
+import type { ESLint } from "eslint";
+import * as jsoncParser from "jsonc-eslint-parser";
+import * as yamlParser from "yaml-eslint-parser";
+import * as tomlParser from "toml-eslint-parser";
+export default [
+  {
+    plugins: {
+      // eslint-disable-next-line @typescript-eslint/naming-convention -- plugin name
+      get "json-schema-validator"(): ESLint.Plugin {
+        // eslint-disable-next-line @typescript-eslint/no-require-imports -- ignore
+        return require("../../index");
+      },
+    },
+  },
+  {
+    files: [
+      "*.json",
+      "**/*.json",
+      "*.json5",
+      "**/*.json5",
+      "*.jsonc",
+      "**/*.jsonc",
+    ],
+    languageOptions: {
+      parser: jsoncParser,
+    },
+    rules: {
+      // ESLint core rules known to cause problems with JSON.
+      strict: "off",
+      "no-unused-expressions": "off",
+      "no-unused-vars": "off",
+    },
+  },
+  {
+    files: ["*.yaml", "**/*.yaml", "*.yml", "**/*.yml"],
+    languageOptions: {
+      parser: yamlParser,
+    },
+    rules: {
+      // ESLint core rules known to cause problems with YAML.
+      "no-irregular-whitespace": "off",
+      "no-unused-vars": "off",
+      "spaced-comment": "off",
+    },
+  },
+  {
+    files: ["*.toml", "**/*.toml"],
+    languageOptions: {
+      parser: tomlParser,
+    },
+    rules: {
+      // ESLint core rules known to cause problems with TOML.
+      "no-irregular-whitespace": "off",
+      "spaced-comment": "off",
+    },
+  },
+];

src/configs/flat/recommended.ts

@@ -0,0 +1,10 @@
+import base from "./base";
+export default [
+  ...base,
+  {
+    rules: {
+      // eslint-plugin-json-schema-validator rules
+      "json-schema-validator/no-invalid": "warn",
+    },
+  },
+];

src/index.ts

@@ -2,11 +2,15 @@ import type { RuleModule } from "./types";
 import { rules as ruleList } from "./utils/rules";
 import base from "./configs/base";
 import recommended from "./configs/recommended";
+import flatBase from "./configs/flat/base";
+import flatRecommended from "./configs/flat/recommended";
 import * as meta from "./meta";
 
 const configs = {
   base,
   recommended,
+  "flat/base": flatBase,
+  "flat/recommended": flatRecommended,
 };
 
 const rules = ruleList.reduce(

tests/fixtures/integrations/eslint-plugin/test01/src/test.js renamed to tests/fixtures/integrations/eslint-plugin/flat-config-test01/src/test.js

@@ -0,0 +1 @@
+var a = {foo: 'bar'}

tests/fixtures/integrations/eslint-plugin/test01/src/test.json renamed to tests/fixtures/integrations/eslint-plugin/flat-config-test01/src/test.json

@@ -0,0 +1 @@
+{"foo": "bar"}

tests/fixtures/integrations/eslint-plugin/test01/.eslintrc.json renamed to tests/fixtures/integrations/eslint-plugin/legacy-config-test01/.eslintrc.json

@@ -1,24 +1,46 @@
 import path from "path";
 import assert from "assert";
 import plugin from "../../src/index";
-import { getLegacyESLint } from "eslint-compat-utils/eslint";
+import semver from "semver";
+import { getLegacyESLint, getESLint } from "eslint-compat-utils/eslint";
 
-// eslint-disable-next-line @typescript-eslint/naming-convention -- Class name
-const ESLint = getLegacyESLint();
 // -----------------------------------------------------------------------------
 // Tests
 // -----------------------------------------------------------------------------
 
-const TEST_CWD = path.join(__dirname, "../fixtures/integrations/eslint-plugin");
+const TEST_FIXTURES_ROOT = path.join(
+  __dirname,
+  "../fixtures/integrations/eslint-plugin",
+);
 
 describe("Integration with eslint-plugin-json-schema-validator", () => {
-  it("should lint without errors", async () => {
+  it("should lint without errors with legacy-config", async () => {
+    // eslint-disable-next-line @typescript-eslint/naming-convention -- Class name
+    const ESLint = getLegacyESLint();
     const engine = new ESLint({
-      cwd: TEST_CWD,
+      cwd: path.join(TEST_FIXTURES_ROOT, "legacy-config-test01"),
       extensions: [".js", ".json"],
       plugins: { "json-schema-validator": plugin as any },
     });
-    const results = await engine.lintFiles(["test01/src"]);
+    const results = await engine.lintFiles(["src"]);
+    assert.strictEqual(results.length, 2);
+    assert.strictEqual(
+      results.reduce((s, r) => s + r.errorCount, 0),
+      0,
+    );
+  });
+  it("should lint without errors with flat-config", async () => {
+    // eslint-disable-next-line @typescript-eslint/naming-convention -- Class name
+    const ESLint = getESLint();
+    if (semver.satisfies(ESLint.version, "<7.0.0")) return;
+    const engine = new ESLint({
+      cwd: path.join(TEST_FIXTURES_ROOT, "flat-config-test01"),
+      // @ts-expect-error -- typing bug
+      overrideConfigFile: true,
+      // @ts-expect-error -- typing bug
+      overrideConfig: plugin.configs["flat/recommended"],
+    });
+    const results = await engine.lintFiles(["src"]);
     assert.strictEqual(results.length, 2);
     assert.strictEqual(
       results.reduce((s, r) => s + r.errorCount, 0),

tests/fixtures/integrations/eslint-plugin/legacy-config-test01/src/test.js

@@ -5,6 +5,9 @@ import os from "os";
 import { rules } from "./lib/load-rules";
 const isWin = os.platform().startsWith("win");
 
+const FLAT_RULESET_NAME = {
+  recommended: "../src/configs/flat/recommended.ts",
+};
 const RULESET_NAME = {
   recommended: "../src/configs/recommended.ts",
   // standard: "../src/configs/standard.ts",
@@ -50,3 +53,41 @@ export = {
   // Update file.
   fs.writeFileSync(filePath, content);
 }
+
+for (const rec of ["recommended"] as const) {
+  let content = `
+import base from './base';
+export default [
+  ...base,
+  {
+    rules: {
+      // eslint-plugin-json-schema-validator rules
+      ${rules
+        .filter(
+          (rule) =>
+            rule.meta.docs.categories &&
+            !rule.meta.deprecated &&
+            rule.meta.docs.categories.includes(rec),
+        )
+        .map((rule) => {
+          const conf = rule.meta.docs.default || "error";
+          return `"${rule.meta.docs.ruleId}": "${conf}"`;
+        })
+        .join(",\n")}
+    },
+  }
+]
+`;
+
+  const filePath = path.resolve(__dirname, FLAT_RULESET_NAME[rec]);
+
+  if (isWin) {
+    content = content
+      .replace(/\r?\n/gu, "\n")
+      .replace(/\r/gu, "\n")
+      .replace(/\n/gu, "\r\n");
+  }
+
+  // Update file.
+  fs.writeFileSync(filePath, content);
+}