Bug 1877792 - Part 12: Add JS::IsCyclicModule r=spidermonkey-reviewers,jonco

Differential Revision: https://phabricator.services.mozilla.com/D218559

js/public/Modules.h

@@ -214,6 +214,11 @@ extern JS_PUBLIC_API void ClearModulePrivate(JSObject* module);
  */
 extern JS_PUBLIC_API Value GetModulePrivate(JSObject* module);
 
+/**
+ * Checks if the given module is a cyclic module.
+ */
+extern JS_PUBLIC_API bool IsCyclicModule(JSObject* module);
+
 /*
  * Perform the ModuleLink operation on the given source text module record.
  *

js/src/vm/Modules.cpp

@@ -214,6 +214,10 @@ JS_PUBLIC_API JS::Value JS::GetModulePrivate(JSObject* module) {
   return module->as<ModuleObject>().scriptSourceObject()->getPrivate();
 }
 
+JS_PUBLIC_API bool JS::IsCyclicModule(JSObject* module) {
+  return module->as<ModuleObject>().hasCyclicModuleFields();
+}
+
 JS_PUBLIC_API bool JS::ModuleLink(JSContext* cx, Handle<JSObject*> moduleArg) {
   AssertHeapIsIdle();
   CHECK_THREAD(cx);