Enzyme (Jest) helper: Creates a HTML context for testing elements that contain a DOM reference (e.g. getElementById) such as the Reactstrap Tooltip.

create-html-container.ts

/**
 * Creates a HTML context for testing elements that require a DOM
 * such as the Tooltip.
 *
 * @returns A tuple with the DOM container and a cleanup function.
 *
 * @example
 * ```typescript
 * let container: HTMLElement;
 * let cleanup: () => void;
 * beforeEach(() => {
 *     [container, cleanup] = withContainer();
 * }
 * afterEach(() => {
 *     cleanup();
 * }
 * it('can render the tooltip', () => {
 *     wrapper = mount(<Tooltip />, { attachTo: container });
 *     expect(wrapper).toBeDefined();
 * }
 * ```
 */
export function withContainer(): [HTMLElement, () => void] {
    let container = document.createElement('div');
    document.body.appendChild(container);

    const cleanup = () => {
        document.body.removeChild(container);
        document.body.innerHTML = '';
        container = null;
    };

    return [container, cleanup];
}