data/frontend/src/__tests__/utils.test.ts

import { describe, it, expect } from "vitest";
import { cn } from "@/lib/utils";

describe("cn() utility", () => {
  it("merges class names correctly", () => {
    expect(cn("foo", "bar")).toBe("foo bar");
  });

  it("handles conditional classes", () => {
    const isHidden = false;
    const isVisible = true;
    expect(cn("base", isHidden && "hidden", isVisible && "visible")).toBe("base visible");
  });

  it("resolves Tailwind conflicts via tailwind-merge", () => {
    expect(cn("px-2", "px-4")).toBe("px-4");
    expect(cn("text-red-500", "text-blue-500")).toBe("text-blue-500");
  });
});