[modules] Don't throw when detecting cycle while processing star exports.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 828fcd896a0607ecd52aacfa7f9a0e49080c15bd..92f24391f8d40d1d904df6eac2651b45ad9d4ec3 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -19707,22 +19707,25 @@ MaybeHandle<Cell> Module::ResolveExport(Handle<Module> module,
     return Handle<Cell>::cast(object);
   }
 
-  // Must be an indirect export of some sort, so we need to detect cycles.
+  // Check for cycle before recursing.
   {
     // Attempt insertion with a null string set.
     auto result = resolve_set->insert({module, nullptr});
     UnorderedStringSet*& name_set = result.first->second;
-    bool did_insert = result.second;
-    if (did_insert) {
+    if (result.second) {
       // |module| wasn't in the map previously, so allocate a new name set.
       Zone* zone = resolve_set->zone();
       name_set =
           new (zone->New(sizeof(UnorderedStringSet))) UnorderedStringSet(zone);
     } else if (name_set->count(name)) {
-      // TODO(adamk): Throwing here is incorrect in the case of star exports.
-      THROW_NEW_ERROR(
-          isolate,
-          NewSyntaxError(MessageTemplate::kCyclicModuleDependency, name), Cell);
+      // Cycle detected.
+      if (must_resolve) {
+        THROW_NEW_ERROR(
+            isolate,
+            NewSyntaxError(MessageTemplate::kCyclicModuleDependency, name),
+            Cell);
+      }
+      return MaybeHandle<Cell>();
     }
     name_set->insert(name);
   }