import { describe, expect, it } from "vitest";
import { formatSize } from "../src/lib/format";

describe("formatSize", () => {
  it("renders human sizes across units", () => {
    expect(formatSize(0)).toBe("");
    expect(formatSize(512)).toBe("512 B");
    expect(formatSize(2048)).toBe("2.0 KB");
    expect(formatSize(15 * 1024 * 1024)).toBe("15 MB");
    expect(formatSize(3.2 * 1024 ** 3)).toBe("3.2 GB");
  });

  it("returns empty for non-positive and keeps one decimal below 10", () => {
    expect(formatSize(-1)).toBe("");
    expect(formatSize(1024)).toBe("1.0 KB");
    expect(formatSize(10 * 1024)).toBe("10 KB");
  });
});