perf(shared): optimize deepEqual

Author: SukkaW

packages/shared/src/openApi/shared/utils/deepEqual.ts

@@ -1 +1,37 @@
-export { dequal as default } from 'dequal/lite';
+/**
+ * Deep equality for JSON-compatible values (objects, arrays, primitives).
+ * Used to determine whether read/write pruned variants actually differ.
+ */
+const deepEqual = (a: unknown, b: unknown): boolean => {
+  if (a === b) return true;
+  if (!a || !b || typeof a !== 'object' || typeof b !== 'object') return false;
+
+  const ctor = (a as object).constructor;
+  if (ctor !== (b as object).constructor) return false;
+
+  // Arrays
+  if (Array.isArray(a)) {
+    const arrA = a as unknown[];
+    const arrB = b as unknown[];
+    let len = arrA.length;
+    if (len !== arrB.length) return false;
+    while (len--) {
+      if (!deepEqual(arrA[len], arrB[len])) return false;
+    }
+    return true;
+  }
+
+  // Plain objects
+  const objA = a as Record<string, unknown>;
+  const objB = b as Record<string, unknown>;
+  let len = 0;
+  for (const key in objA) {
+    if (Object.hasOwn(objA, key)) {
+      if (++len && !Object.hasOwn(objB, key)) return false;
+      if (!deepEqual(objA[key], objB[key])) return false;
+    }
+  }
+  return Object.keys(objB).length === len;
+};
+
+export default deepEqual;