improve impl of isEqual

index.ts

@@ -223,11 +223,24 @@ export default class YGOProDeck implements YGOProDeckLike {
     } = {},
   ): boolean {
     const { ignoreOrder = false } = options;
+    const fields = ['main', 'extra', 'side'] as const;
+    const getField = (o: YGOProDeckLike, field: (typeof fields)[number]) =>
+      o[field] || [];
+    if (
+      fields.some(
+        (field) =>
+          getField(this, field).length !== getField(other, field).length,
+      )
+    ) {
+      return false;
+    }
     const normalize = (arr: number[]) =>
       ignoreOrder ? [...arr].sort((a, b) => a - b) : arr;
-    const fields = ['main', 'extra', 'side'] as const;
     return fields.every((field) =>
-      arrayEquals(normalize(this[field]), normalize(other[field] || [])),
+      arrayEquals(
+        normalize(getField(this, field)),
+        normalize(getField(other, field)),
+      ),
     );
   }
 }

src/utils.ts

@@ -175,9 +175,5 @@ export class BufferReader extends BufferCursor {
 }
 
 export const arrayEquals = <T>(a: T[], b: T[]): boolean => {
-  if (a.length !== b.length) return false;
-  for (let i = 0; i < a.length; i++) {
-    if (a[i] !== b[i]) return false;
-  }
-  return true;
+  return a.length === b.length && a.every((v, i) => v === b[i]);
 };