diff --git a/resources/js/tests/datetime.test.ts b/resources/js/tests/datetime.test.ts
index a130bf1..01d4d12 100644
--- a/resources/js/tests/datetime.test.ts
+++ b/resources/js/tests/datetime.test.ts
@@ -1,33 +1,33 @@
 import { expect, describe, it } from "vitest";
-import { format } from "../helpers/datetime";
+import { SMDate } from "../helpers/datetime";
 
 describe("format()", () => {
     it("should return an empty string when the first argument is not a Date object", () => {
-        const result = format("not a date", "yyyy-MM-dd");
+        const result = new SMDate("not a date").format("yyyy-MM-dd");
         expect(result).toEqual("");
     });
 
     it("should format the date correctly", () => {
         const date = new Date("2022-02-19T12:34:56");
-        const result = format(date, "yyyy-MM-dd HH:mm:ss");
+        const result = new SMDate(date).format("yyyy-MM-dd HH:mm:ss");
         expect(result).toEqual("2022-02-19 12:34:56");
     });
 
     it("should handle single-digit month and day", () => {
         const date = new Date("2022-01-01T00:00:00");
-        const result = format(date, "yy-M-d");
+        const result = new SMDate(date).format("yy-M-d");
         expect(result).toEqual("22-1-1");
     });
 
     it("should handle day of week and month name abbreviations", () => {
         const date = new Date("2022-03-22T00:00:00");
-        const result = format(date, "EEE, MMM dd, yyyy");
+        const result = new SMDate(date).format("EEE, MMM dd, yyyy");
         expect(result).toEqual("Tue, Mar 22, 2022");
     });
 
     it("should handle 12-hour clock with am/pm", () => {
         const date = new Date("2022-01-01T12:34:56");
-        const result = format(date, "hh:mm:ss aa");
+        const result = new SMDate(date).format("hh:mm:ss aa");
         expect(result).toEqual("12:34:56 pm");
     });
 });