feat: Add globalIgnores helper function (#159)

Co-authored-by: Milos Djermanovic <[email protected]>

Author: nzakas

packages/config-helpers/README.md

@@ -54,6 +54,26 @@ export default defineConfig([
 ]);
 ```
 
+### `globalIgnores()`
+
+The `globalIgnores()` function allows you to specify patterns for files and directories that should be globally ignored by ESLint. This is useful for excluding files that you don't want to lint, such as build directories or third-party libraries. Here's an example:
+
+```js
+// eslint.config.js
+import { defineConfig, globalIgnores } from "@eslint/config-helpers";
+
+export default defineConfig([
+	{
+		files: ["src/**/*.js"],
+		rules: {
+			semi: "error",
+			"prefer-const": "error",
+		},
+	},
+	globalIgnores(["node_modules/", "dist/", "coverage/"]),
+]);
+```
+
 ## License
 
 Apache 2.0

packages/config-helpers/package.json

@@ -25,8 +25,9 @@
     "test": "tests"
   },
   "scripts": {
+    "build:dedupe-types": "node ../../tools/dedupe-types.js dist/cjs/index.cjs dist/esm/index.js",
     "build:cts": "node ../../tools/build-cts.js dist/esm/index.d.ts dist/cjs/index.d.cts",
-    "build": "rollup -c && tsc -p tsconfig.esm.json && npm run build:cts",
+    "build": "rollup -c && npm run build:dedupe-types && tsc -p tsconfig.esm.json && npm run build:cts",
     "test:jsr": "npx jsr@latest publish --dry-run",
     "test": "mocha tests/*.js",
     "test:coverage": "c8 npm test",

packages/config-helpers/src/global-ignores.js

@@ -0,0 +1,43 @@
+/**
+ * @fileoverview Global ignores helper function.
+ * @author Nicholas C. Zakas
+ */
+
+//-----------------------------------------------------------------------------
+// Type Definitions
+//-----------------------------------------------------------------------------
+
+/** @typedef {import("eslint").Linter.Config} Config */
+
+//-----------------------------------------------------------------------------
+// Helpers
+//-----------------------------------------------------------------------------
+
+let globalIgnoreCount = 0;
+
+//-----------------------------------------------------------------------------
+// Exports
+//-----------------------------------------------------------------------------
+
+/**
+ * Creates a global ignores config with the given patterns.
+ * @param {string[]} ignorePatterns The ignore patterns.
+ * @param {string} [name] The name of the global ignores config.
+ * @returns {Config} The global ignores config.
+ */
+export function globalIgnores(ignorePatterns, name) {
+	if (!Array.isArray(ignorePatterns)) {
+		throw new TypeError("ignorePatterns must be an array");
+	}
+
+	if (ignorePatterns.length === 0) {
+		throw new TypeError("ignorePatterns must contain at least one pattern");
+	}
+
+	const id = globalIgnoreCount++;
+
+	return {
+		name: name || `globalIgnores ${id}`,
+		ignores: ignorePatterns,
+	};
+}

packages/config-helpers/src/index.js

@@ -2,4 +2,5 @@
  * @fileoverview Main entrypoint for the package.
  */
 
-export * from "./define-config.js";
+export { defineConfig } from "./define-config.js";
+export { globalIgnores } from "./global-ignores.js";

packages/config-helpers/tests/global-ignores.test.js

@@ -0,0 +1,61 @@
+/**
+ * @fileoverview Tests for globalIgnores()
+ * @author Nicholas C. Zakas
+ */
+
+//-----------------------------------------------------------------------------
+// Imports
+//-----------------------------------------------------------------------------
+
+import assert from "node:assert";
+import { globalIgnores } from "../src/global-ignores.js";
+
+//-----------------------------------------------------------------------------
+// Tests
+//-----------------------------------------------------------------------------
+
+describe("globalIgnores", () => {
+	it("should create config with custom name", () => {
+		const result = globalIgnores(["*.test.js"], "custom-name");
+		assert.deepStrictEqual(result, {
+			name: "custom-name",
+			ignores: ["*.test.js"],
+		});
+	});
+
+	it("should create config with auto-generated name", () => {
+		const result = globalIgnores(["*.test.js"]);
+		assert.strictEqual(result.name.startsWith("globalIgnores "), true);
+		assert.deepStrictEqual(result.ignores, ["*.test.js"]);
+	});
+
+	it("should increment auto-generated names", () => {
+		const result1 = globalIgnores(["*.test.js"]);
+		const result2 = globalIgnores(["*.spec.js"]);
+		assert.notStrictEqual(result1.name, result2.name);
+	});
+
+	it("should throw error for non-array input", () => {
+		assert.throws(
+			() => {
+				globalIgnores("*.test.js");
+			},
+			{
+				name: "TypeError",
+				message: "ignorePatterns must be an array",
+			},
+		);
+	});
+
+	it("should throw error for empty array", () => {
+		assert.throws(
+			() => {
+				globalIgnores([]);
+			},
+			{
+				name: "TypeError",
+				message: "ignorePatterns must contain at least one pattern",
+			},
+		);
+	});
+});

packages/config-helpers/tests/index.test.js

@@ -17,4 +17,8 @@ describe("index", () => {
 	it("should export defineConfig()", () => {
 		assert.strictEqual(typeof api.defineConfig, "function");
 	});
+
+	it("should export globalIgnores()", () => {
+		assert.strictEqual(typeof api.globalIgnores, "function");
+	});
 });

packages/config-helpers/tests/types/types.test.ts

@@ -7,7 +7,7 @@
 // Imports
 //-----------------------------------------------------------------------------
 
-import { defineConfig } from "@eslint/config-helpers";
+import { defineConfig, globalIgnores } from "@eslint/config-helpers";
 
 //-----------------------------------------------------------------------------
 // Type Checking
@@ -17,7 +17,7 @@ defineConfig({});
 defineConfig({}, {});
 defineConfig([]);
 defineConfig([], {});
-defineConfig([], []);
+defineConfig([globalIgnores(["node_modules"])], []);
 defineConfig([{}]);
 defineConfig({
 	extends: [],
@@ -43,23 +43,31 @@ defineConfig({
 	],
 });
 
-defineConfig({
-	settings: {
-		react: {
-			version: "detect",
+defineConfig([
+	{
+		settings: {
+			react: {
+				version: "detect",
+			},
 		},
 	},
-});
+]);
 
-defineConfig({
-	extends: [
-		[
-			[{ rules: { "no-alert": "warn" } }],
-			{ rules: { "no-debugger": "error" } },
-		],
-		[
-			{ rules: { "no-eval": "error" } },
-			{ rules: { "no-implied-eval": "error" } },
+defineConfig(
+	{
+		extends: [
+			[
+				[{ rules: { "no-alert": "warn" } }],
+				{ rules: { "no-debugger": "error" } },
+			],
+			[
+				{ rules: { "no-eval": "error" } },
+				{ rules: { "no-implied-eval": "error" } },
+			],
 		],
-	],
-});
+	},
+	globalIgnores(["node_modules"]),
+);
+
+globalIgnores(["node_modules"]);
+globalIgnores(["dist", "build"], "my name");