fix(esm): misleading when import empty package.json

Author: himself65

lib/internal/modules/esm/resolve.js

@@ -183,6 +183,12 @@ function legacyMainResolve(packageJSONUrl, packageConfig, base) {
 
   const baseStringified = isURL(base) ? base.href : base;
 
+  if (typeof packageConfig.main !== 'string') {
+    throw new ERR_INVALID_PACKAGE_CONFIG(
+      fileURLToPath(packageJSONUrl), base,
+      '"main" must be a string', 'main');
+  }
+
   const resolvedOption = FSLegacyMainResolve(packageJsonUrlString, packageConfig.main, baseStringified);
 
   const baseUrl = resolvedOption <= legacyMainResolveExtensionsIndexes.kResolvedByMainIndexNode ? `./${packageConfig.main}` : '';

test/es-module/test-import-empty.js

@@ -0,0 +1,23 @@
+'use strict';
+
+const { spawnPromisified } = require('../common');
+const fixtures = require('../common/fixtures.js');
+const assert = require('node:assert');
+const { execPath } = require('node:process');
+const { describe, it } = require('node:test');
+
+describe('Import empty module', { concurrency: true }, () => {
+  it(async () => {
+    const { code, signal, stdout, stderr } = await spawnPromisified(execPath, [
+      '--no-warnings',
+      '--eval',
+      'import("empty")',
+    ], {
+      cwd: fixtures.path(),
+    });
+    assert.strictEqual(code, 1);
+    assert.strictEqual(signal, null);
+    assert.strictEqual(stdout, '');
+    assert.match(stderr, /Error \[ERR_INVALID_PACKAGE_CONFIG]: Invalid package config/);
+  });
+});