import { describe, expect, it } from "vitest";

import { cn } from "@/lib/utils";

describe("cn", () => {
  it("joins truthy class values", () => {
    expect(cn("a", "b")).toBe("a b");
  });

  it("ignores falsey values", () => {
    expect(cn("a", false, null, undefined, "", "b")).toBe("a b");
  });

  it("supports conditional object syntax", () => {
    expect(cn("base", { active: true, hidden: false })).toBe("base active");
  });

  it("merges conflicting tailwind classes, last wins", () => {
    expect(cn("px-2", "px-4")).toBe("px-4");
    expect(cn("text-sm text-red-500", "text-lg")).toBe("text-red-500 text-lg");
  });

  it("flattens arrays", () => {
    expect(cn(["a", "b"], "c")).toBe("a b c");
  });
});