fix: add cjs override for esm projects (fixes #59) (#63)

* fix: add `globals module` in generated .eslintrc.js (fixes #59)

see the discussion: #59 (comment)

* --wip-- [skip ci]

* fix: add cjs override for esm projects (fixes #59)

* Update config-initializer.js

lib/init/config-initializer.js

@@ -24,6 +24,24 @@ const { ConfigOps, naming, ModuleResolver } = Legacy;
 // Private
 //------------------------------------------------------------------------------
 
+/**
+ * check if the package.type === "module"
+ * @returns {boolean} return true if the package.type === "module"
+ */
+function isPackageTypeModule() {
+ const pkgJSONPath = npmUtils.findPackageJson();
+
+ if (pkgJSONPath) {
+ const pkgJSONContents = JSON.parse(fs.readFileSync(pkgJSONPath, "utf8"));
+
+ if (pkgJSONContents.type === "module") {
+ return true;
+ }
+ }
+
+ return false;
+}
+
 /* istanbul ignore next: hard to test fs function */
 /**
  * Create .eslintrc file in the current working directory
@@ -41,14 +59,8 @@ async function writeFile(config, format) {
  } else if (format === "JSON") {
  extname = ".json";
  } else if (format === "JavaScript") {
- const pkgJSONPath = npmUtils.findPackageJson();
-
- if (pkgJSONPath) {
- const pkgJSONContents = JSON.parse(fs.readFileSync(pkgJSONPath, "utf8"));
-
- if (pkgJSONContents.type === "module") {
- extname = ".cjs";
- }
+ if (isPackageTypeModule()) {
+ extname = ".cjs";
  }
  }
 
@@ -163,6 +175,14 @@ function processAnswers(answers) {
  config.parserOptions.ecmaVersion = "latest";
  config.env.es2021 = true;
 
+ if (answers.format === "JavaScript") {
+ config.overrides.push({
+ files: [".eslintrc.{js,cjs}"],
+ parserOptions: { sourceType: "script" },
+ env: { node: true }
+ });
+ }
+
  // set the module type
  if (answers.moduleType === "esm") {
  config.parserOptions.sourceType = "module";

tests/init/config-initializer.js

@@ -230,6 +230,18 @@ describe("configInitializer", () => {
 
  assert.isTrue(config.env.commonjs);
  });
+
+ it("should set commonjs config for `.eslintrc.cjs` in esm projects", () => {
+ answers.moduleType = "esm";
+ answers.format = "JavaScript";
+ const config = init.processAnswers(answers);
+
+ assert.isArray(config.overrides, "should have overrides config");
+ assert.strictEqual(config.overrides.length, 1);
+ assert.deepStrictEqual(config.overrides[0].parserOptions, { sourceType: "script" });
+ assert.deepStrictEqual(config.overrides[0].env, { node: true });
+ });
+
  });
 
  describe("guide", () => {