carbon-components-svelte/tests/Pagination/Pagination.test.ts

import { render, screen, within } from "@testing-library/svelte";
import { user } from "../setup-tests";
import Pagination from "./Pagination.test.svelte";

describe("Pagination", () => {
  beforeEach(() => {
    vi.clearAllMocks();
  });

  it("should render with default props", () => {
    render(Pagination);

    expect(screen.getByText("Items per page:")).toBeInTheDocument();
    expect(
      screen.getByRole("button", { name: "Next page" }),
    ).toBeInTheDocument();
    expect(
      screen.getByRole("button", { name: "Previous page" }),
    ).toBeInTheDocument();
  });

  it("should render with custom total items", () => {
    render(Pagination, {
      props: { totalItems: 102 },
    });

    expect(screen.getByText("1–10 of 102 items")).toBeInTheDocument();
  });

  it("should handle custom page sizes", () => {
    render(Pagination, {
      props: {
        totalItems: 102,
        pageSizes: [10, 15, 20],
        pageSize: 15,
      },
    });

    const select = screen.getByRole("combobox", { name: "Items per page:" });
    expect(select).toHaveValue("15");

    const options = within(select).getAllByRole("option");
    expect(options).toHaveLength(3);
    expect(options[0]).toHaveTextContent("10");
    expect(options[1]).toHaveTextContent("15");
    expect(options[2]).toHaveTextContent("20");
  });

  it("should handle page navigation", async () => {
    const consoleLog = vi.spyOn(console, "log");
    render(Pagination, {
      props: { totalItems: 102, page: 1 },
    });

    const nextButton = screen.getByRole("button", { name: "Next page" });
    await user.click(nextButton);
    expect(consoleLog).toHaveBeenCalledWith("next", { page: 2 });
    expect(consoleLog).toHaveBeenCalledWith("change", { page: 2 });

    const prevButton = screen.getByRole("button", { name: "Previous page" });
    await user.click(prevButton);
    expect(consoleLog).toHaveBeenCalledWith("previous", { page: 1 });
    expect(consoleLog).toHaveBeenCalledWith("change", { page: 1 });
  });

  it("should handle page size changes", async () => {
    const consoleLog = vi.spyOn(console, "log");
    render(Pagination, {
      props: {
        totalItems: 102,
        pageSizes: [10, 15, 20],
      },
    });

    const select = screen.getByRole("combobox", { name: "Items per page:" });
    await user.selectOptions(select, "15");

    expect(consoleLog).toHaveBeenCalledWith("change", { pageSize: 10 });
    expect(consoleLog).toHaveBeenCalledWith("update", {
      pageSize: 15,
      page: 1,
    });
  });

  it("should handle page selection", async () => {
    const consoleLog = vi.spyOn(console, "log");
    render(Pagination, {
      props: { totalItems: 102, pageSizes: [5, 10, 15] },
    });

    const pageSelect = screen.getAllByRole("combobox");
    await user.selectOptions(pageSelect[0], "5");

    expect(consoleLog).toHaveBeenCalledWith("change", { pageSize: 10 });
    expect(consoleLog).toHaveBeenCalledWith("update", { pageSize: 5, page: 1 });
  });

  it("should disable navigation buttons when disabled", () => {
    render(Pagination, {
      props: { disabled: true },
    });

    const prevButton = screen.getByRole("button", { name: "Previous page" });
    const nextButton = screen.getByRole("button", { name: "Next page" });

    expect(prevButton).toBeDisabled();
    expect(nextButton).toBeDisabled();
  });

  it("should handle custom button text", () => {
    render(Pagination, {
      props: {
        forwardText: "Next",
        backwardText: "Previous",
      },
    });

    expect(
      screen.getByRole("button", { name: "Previous" }),
    ).toBeInTheDocument();
    expect(screen.getByRole("button", { name: "Next" })).toBeInTheDocument();
  });

  it("should handle custom items per page text", () => {
    render(Pagination, {
      props: {
        itemsPerPageText: "Show:",
      },
    });

    expect(screen.getByText("Show:")).toBeInTheDocument();
  });

  it("should handle disabled page input", () => {
    render(Pagination, {
      props: { pageInputDisabled: true },
    });

    expect(
      screen.queryByRole("combobox", { name: "Page number" }),
    ).not.toBeInTheDocument();
  });

  it("should handle disabled page size input", () => {
    render(Pagination, {
      props: { pageSizeInputDisabled: true },
    });

    expect(
      screen.queryByRole("combobox", { name: "Items per page:" }),
    ).not.toBeInTheDocument();
  });

  it("should handle unknown pages", () => {
    render(Pagination, {
      props: { pagesUnknown: true },
    });

    expect(screen.getByText("1–10 items")).toBeInTheDocument();
    expect(screen.getByText("page 1")).toBeInTheDocument();
  });

  it("should update when page or pageSize changes", async () => {
    const consoleLog = vi.spyOn(console, "log");
    render(Pagination, {
      props: { totalItems: 102, pageSizes: [5, 10, 15] },
    });

    // Change page size
    const pageSizeSelect = screen.getAllByRole("combobox");
    await user.selectOptions(pageSizeSelect[0], "15");
    expect(consoleLog).toHaveBeenCalledWith("change", { pageSize: 10 });
    expect(consoleLog).toHaveBeenCalledWith("update", {
      pageSize: 15,
      page: 1,
    });

    // Change page
    const pageSelect = screen.getAllByRole("combobox");
    await user.selectOptions(pageSelect[1], "2");
    expect(consoleLog).toHaveBeenCalledWith("change", { pageSize: 10 });
    expect(consoleLog).toHaveBeenCalledWith("update", {
      pageSize: 15,
      page: 2,
    });
  });

  it("should handle edge cases", () => {
    render(Pagination, {
      props: {
        totalItems: 0,
        page: 1,
        pageSize: 10,
      },
    });

    expect(screen.getByText("0–0 of 0 items")).toBeInTheDocument();
  });

  it("renders a cap of 1000 page numbers by default", () => {
    render(Pagination, {
      props: { totalItems: 100_000 },
    });

    const pageNumbers = screen.getByLabelText(/Page number, of 10000 pages/);
    expect(pageNumbers).toHaveLength(1_000 + 1);
  });

  it("renders a custom page window", () => {
    render(Pagination, {
      props: { totalItems: 100_000, pageWindow: 100 },
    });

    const pageNumbers = screen.getByLabelText(/Page number, of 10000 pages/);
    expect(pageNumbers).toHaveLength(100 + 1);
  });
});