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

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

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

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

    expect(screen.getByText("Contact")).toBeInTheDocument();
    const input = screen.getByRole("textbox");
    expect(input).toHaveAttribute("placeholder", "Select contact method");
  });

  it("should open menu on click", async () => {
    render(ComboBox);

    const input = screen.getByRole("textbox");
    await user.click(input);

    const dropdown = screen.getAllByRole("listbox")[1];
    expect(dropdown).toBeVisible();
  });

  it("should handle item selection", async () => {
    const consoleLog = vi.spyOn(console, "log");
    render(ComboBox);

    await user.click(screen.getByRole("textbox"));
    await user.click(screen.getByText("Email"));

    expect(consoleLog).toHaveBeenCalledWith("select", {
      selectedId: "1",
      selectedItem: { id: "1", text: "Email" },
    });
    expect(screen.getByRole("textbox")).toHaveValue("Email");
  });

  it("should handle keyboard navigation", async () => {
    render(ComboBox);

    const input = screen.getByRole("textbox");
    await user.click(input);
    await user.keyboard("{ArrowDown}");
    await user.keyboard("{Enter}");

    expect(input).toHaveValue("Slack");
  });

  it("should handle clear selection", async () => {
    const consoleLog = vi.spyOn(console, "log");
    render(ComboBox, {
      props: {
        selectedId: "1",
        value: "Email",
      },
    });

    const clearButton = screen.getByRole("button", { name: /clear/i });
    await user.click(clearButton);

    expect(consoleLog).toHaveBeenCalledWith("clear", expect.any(String));
    expect(screen.getByRole("textbox")).toHaveValue("");
  });

  it("should handle disabled state", () => {
    render(ComboBox, { props: { disabled: true } });

    expect(screen.getByRole("textbox")).toBeDisabled();
    expect(screen.getByText("Contact")).toHaveClass("bx--label--disabled");
  });

  it("should handle invalid state", () => {
    render(ComboBox, {
      props: {
        invalid: true,
        invalidText: "Invalid selection",
      },
    });

    expect(screen.getByRole("listbox")).toHaveAttribute("data-invalid", "true");
    expect(screen.getByText("Invalid selection")).toBeInTheDocument();
  });

  it("should handle warning state", () => {
    render(ComboBox, {
      props: {
        warn: true,
        warnText: "Warning message",
      },
    });

    expect(screen.getByText("Warning message")).toBeInTheDocument();
  });

  it("should handle helper text", () => {
    render(ComboBox, { props: { helperText: "Helper message" } });

    expect(screen.getByText("Helper message")).toBeInTheDocument();
  });

  it("should handle light variant", () => {
    render(ComboBox, { props: { light: true } });

    expect(screen.getByRole("textbox")).toHaveClass("bx--text-input--light");
  });

  test.each([
    ["sm", "bx--list-box--sm"],
    ["xl", "bx--list-box--xl"],
  ] as const)("should handle size variants", (size, className) => {
    render(ComboBox, { props: { size } });
    expect(screen.getByRole("listbox")).toHaveClass(className);
  });

  it("should handle filtering items", async () => {
    render(ComboBox);

    const input = screen.getByRole("textbox");
    await user.click(input);
    await user.type(input, "em");

    const options = screen.getAllByRole("option");
    expect(options).toHaveLength(1);
    expect(options[0]).toHaveTextContent("Email");

    await user.clear(input);
    expect(input).toHaveValue("");
    expect(screen.getAllByRole("option")).toHaveLength(3);

    await user.click(document.body);
    expect(input).not.toHaveFocus();

    await user.keyboard("{Tab}");
    expect(input).toHaveFocus();

    await user.type(input, "a");
    await user.click(screen.getAllByRole("option")[1]);
    expect(input).toHaveValue("Email");
    
    await user.click(document.body);
    expect(input).not.toHaveFocus();
    expect(screen.queryByRole("option")).not.toBeInTheDocument();
  });

  it("should handle disabled items", async () => {
    render(ComboBoxCustom);

    await user.click(screen.getByRole("textbox"));
    const disabledOption = screen.getByText(/Fax/).closest('[role="option"]');
    assert(disabledOption);
    expect(disabledOption).toHaveAttribute("disabled", "true");

    await user.click(disabledOption);
    expect(screen.getByRole("textbox")).toHaveValue("");

    // Dropdown remains open
    const dropdown = screen.getAllByRole("listbox")[1];
    expect(dropdown).toBeVisible();
  });

  it("should handle custom item display", async () => {
    render(ComboBoxCustom);

    await user.click(screen.getByRole("textbox"));
    const options = screen.getAllByRole("option");

    expect(options[0]).toHaveTextContent("Item Slack");
    expect(options[1]).toHaveTextContent("Item Email");
    expect(options[2]).toHaveTextContent("Item Fax");
  });

  it("should handle top direction", async () => {
    render(ComboBoxCustom, { props: { direction: "top" } });

    await user.click(screen.getAllByRole("button")[0]);
    expect(screen.getByRole("listbox")).toHaveClass("bx--list-box--up");
  });

  it("should programmatically clear selection", async () => {
    render(ComboBoxCustom, { props: { selectedId: "1" } });

    expect(screen.getByRole("textbox")).toHaveValue("Email");
    await user.click(screen.getByText("Clear"));
    expect(screen.getByRole("textbox")).toHaveValue("");
  });

  it("should close menu on Escape key", async () => {
    render(ComboBox);

    const input = screen.getByRole("textbox");
    await user.click(input);

    const dropdown = screen.getAllByRole("listbox")[1];
    expect(dropdown).toBeVisible();

    await user.keyboard("{Escape}");
    expect(dropdown).not.toBeVisible();
  });
});