Function createMouseEvent

src/cdk/testing/testbed/fake-events/event-objects.ts:18–64

(
  type: string,
  clientX = 0,
  clientY = 0,
  offsetX = 0,
  offsetY = 0,
  button = 0,
  modifiers: ModifierKeys = {},
)

 * @docs-private
 */
export function createMouseEvent(
  type: string,
  clientX = 0,
  clientY = 0,
  offsetX = 0,
  offsetY = 0,
  button = 0,
  modifiers: ModifierKeys = {},
) {
  // Note: We cannot determine the position of the mouse event based on the screen
  // because the dimensions and position of the browser window are not available
  // To provide reasonable `screenX` and `screenY` coordinates, we simply use the
  // client coordinates as if the browser is opened in fullscreen.
  const screenX = clientX;
  const screenY = clientY;

  const event = new MouseEvent(type, {
    bubbles: true,
    cancelable: true,
    composed: true, // Required for shadow DOM events.
    view: getEventView(),
    detail: 1,
    relatedTarget: null,
    screenX,
    screenY,
    clientX,
    clientY,
    ctrlKey: modifiers.control,
    altKey: modifiers.alt,
    shiftKey: modifiers.shift,
    metaKey: modifiers.meta,
    button: button,
    buttons: 1,
  });

  // The `MouseEvent` constructor doesn't allow us to pass these properties into the constructor.
  // Override them to `1`, because they're used for fake screen reader event detection.
  if (offsetX != null) {
    defineReadonlyEventProperty(event, 'offsetX', offsetX);
  }

  if (offsetY != null) {
    defineReadonlyEventProperty(event, 'offsetY', offsetY);
  }

  return event;
}

/**
 * Creates a browser `PointerEvent` with the specified options. Pointer events