util: introduce types.isModuleNamespaceObject

PR-URL: #20016
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Guy Bedford <guybedford@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

Author: devsnek

src/node_types.cc

@@ -34,6 +34,7 @@ namespace {
   V(SharedArrayBuffer)                                                        \
   V(Proxy)                                                                    \
   V(WebAssemblyCompiledModule)                                                \
+  V(ModuleNamespaceObject)                                                    \
 
 
 #define V(type) \

test/parallel/test-util-types.js

@@ -1,4 +1,4 @@
-// Flags: --harmony-bigint
+// Flags: --harmony-bigint --experimental-vm-modules
 /* global SharedArrayBuffer */
 'use strict';
 const common = require('../common');
@@ -126,3 +126,11 @@ for (const [ value, _method ] of [
     assert.deepStrictEqual(yup, expected[testedFunc]);
   }
 }
+
+(async () => {
+  const m = new vm.Module('');
+  await m.link(() => 0);
+  m.instantiate();
+  await m.evaluate();
+  assert.ok(types.isModuleNamespaceObject(m.namespace));
+})();