[environment] Don't print warning for enum object groups

Change-Id: I804f24170903e3588552022b2a403dab27f3f9a4
Reviewed-on: https://chrome-internal-review.googlesource.com/c/v8/fuzzilli/+/8738176
Reviewed-by: Danylo Mocherniuk <mdanylo@google.com>
Auto-Submit: Matthias Liedtke <mliedtke@google.com>
Commit-Queue: Matthias Liedtke <mliedtke@google.com>
Commit-Queue: Danylo Mocherniuk <mdanylo@google.com>

Author: Liedtke

Sources/Fuzzilli/Environment/JavaScriptEnvironment.swift

@@ -830,8 +830,8 @@ public class JavaScriptEnvironment: ComponentBase {
                 if let signatures = group.methods[propertyName] {
                     return .unboundFunction(signatures.first, receiver: baseType)
                 }
-            } else {
-                // This shouldn't happen, probably forgot to register the object group
+            } else if !baseType.isEnumerationOrNamedString {
+                // This shouldn't happen, probably forgot to register the object group.
                 logger.warning("No type information for object group \(groupName) available")
             }
         }
@@ -845,7 +845,7 @@ public class JavaScriptEnvironment: ComponentBase {
                 if let signatures = group.methods[methodName] {
                     return signatures
                 }
-            } else {
+            } else if !baseType.isEnumerationOrNamedString {
                 // This shouldn't happen, probably forgot to register the object group
                 logger.warning("No type information for object group \(groupName) available")
             }

Sources/Fuzzilli/FuzzIL/TypeSystem.swift

@@ -493,10 +493,14 @@ public struct ILType: Hashable {
         return Is(.constructor()) ? ext?.signature : nil
     }
 
-    public var isEnumeration : Bool {
+    public var isEnumeration: Bool {
         return Is(.string) && ext != nil && !ext!.properties.isEmpty
     }
 
+    public var isEnumerationOrNamedString: Bool {
+        return Is(.string) && ext != nil && group != nil
+    }
+
     public var group: String? {
         return ext?.group
     }