Move .isEmpty to $isEmpty (#5424)

* Move .isEmpty to $isEmpty

* Adjust usages

packages/typegen/src/metadataMd.ts

@@ -232,7 +232,7 @@ function addConstants ({ lookup, pallets }: MetadataLatest): string {
     description: DESC_CONSTANTS,
     sections: pallets
       .sort(sortByName)
-      .filter(({ constants }) => !constants.isEmpty)
+      .filter(({ constants }) => !constants.$isEmpty)
       .map(({ constants, name }) => {
         const sectionName = stringLowerFirst(name);
 

packages/typegen/src/util/derived.ts

@@ -67,10 +67,10 @@ export function getSimilarTypes (registry: Registry, definitions: Record<string,
       }
     }
   } else if (isChildClass(Enum, Clazz)) {
-    const { defKeys, isBasic } = new (Clazz as Constructor)(registry) as Enum;
+    const { $isBasic, defKeys } = new (Clazz as Constructor)(registry) as Enum;
     const keys = defKeys.filter((v) => !v.startsWith('__Unused'));
 
-    if (isBasic) {
+    if ($isBasic) {
       possibleTypes.push(arrayToStrType(keys), 'number');
     } else {
       // TODO We don't really want any here, these should be expanded