module,win: fix long path resolve

src/node_modules.cc

@@ -256,8 +256,15 @@ void BindingData::ReadPackageJSON(const FunctionCallbackInfo<Value>& args) {
       permission::PermissionScope::kFileSystemRead,
       path.ToStringView());
 
+  // TODO(StefanStojanovic): Remove ifdef after
+  // path.toNamespacedPath logic is ported to C++
+#ifdef _WIN32
+  auto package_json = GetPackageJSON(
+      realm, "\\\\?\\" + path.ToString(), is_esm ? &error_context : nullptr);
+#else
   auto package_json =
       GetPackageJSON(realm, path.ToString(), is_esm ? &error_context : nullptr);
+#endif
   if (package_json == nullptr) {
     return;
   }

test/es-module/test-GH-50753.js

@@ -0,0 +1,42 @@
+'use strict';
+
+// Flags: --expose-internals
+
+const common = require('../common');
+if (!common.isWindows) {
+  common.skip('this test is Windows-specific.');
+}
+
+const fs = require('fs');
+const path = require('path');
+const tmpdir = require('../common/tmpdir');
+
+// https://github.com/nodejs/node/issues/50753
+// Make a path that is more than 260 chars long.
+// Module layout will be the following:
+//  package.json
+//  main
+//    main.js
+
+const packageDirNameLen = Math.max(260 - tmpdir.path.length, 1);
+const packageDirName = tmpdir.resolve('x'.repeat(packageDirNameLen));
+const packageDirPath = path.resolve(packageDirName);
+const packageJsonFilePath = path.join(packageDirPath, 'package.json');
+const mainDirName = 'main';
+const mainDirPath = path.resolve(packageDirPath, mainDirName);
+const mainJsFile = 'main.js';
+const mainJsFilePath = path.resolve(mainDirPath, mainJsFile);
+
+tmpdir.refresh();
+
+fs.mkdirSync(packageDirPath);
+fs.writeFileSync(
+  packageJsonFilePath,
+  `{"main":"${mainDirName}/${mainJsFile}"}`
+);
+fs.mkdirSync(mainDirPath);
+fs.writeFileSync(mainJsFilePath, 'console.log("hello world");');
+
+require('internal/modules/run_main').executeUserEntryPoint(packageDirPath);
+
+tmpdir.refresh();

test/es-module/test-esm-invalid-pjson.js

@@ -3,6 +3,7 @@
 const { spawnPromisified } = require('../common');
 const fixtures = require('../common/fixtures.js');
 const assert = require('node:assert');
+const path = require('node:path');
 const { execPath } = require('node:process');
 const { describe, it } = require('node:test');
 
@@ -17,7 +18,7 @@ describe('ESM: Package.json', { concurrency: true }, () => {
     assert.ok(stderr.includes('code: \'ERR_INVALID_PACKAGE_CONFIG\''), stderr);
     assert.ok(
       stderr.includes(
-        `Invalid package config ${invalidJson} while importing "invalid-pjson" from ${entry}.`
+        `Invalid package config ${path.toNamespacedPath(invalidJson)} while importing "invalid-pjson" from ${entry}.`
       ),
       stderr
     );

test/sequential/test-module-loading.js

@@ -110,7 +110,7 @@ assert.strictEqual(require('../fixtures/packages/main-index').ok, 'ok');
 common.expectWarning(
   'DeprecationWarning',
   "Invalid 'main' field in '" +
-  require.resolve('../fixtures/packages/missing-main/package.json') +
+  path.toNamespacedPath(require.resolve('../fixtures/packages/missing-main/package.json')) +
   "' of 'doesnotexist.js'. Please either fix that or report it to the" +
   ' module author',
   'DEP0128');