code: function calculateMirrorOffset({sensorEvent, sourceRect, options, ...args}) {
    return withPromise((resolve) => {
      const top = options.cursorOffsetY === null ? sensorEvent.clientY - sourceRect.top : options.cursorOffsetY;
      const left = options.cursorOffsetX === null ? sensorEvent.clientX - sourceRect.left : options.cursorOffsetX;
  
      const mirrorOffset = {top, left};
  
      resolve({sensorEvent, sourceRect, mirrorOffset, options, ...args});
    });
  }
docs: Calculates mirror offset
  Adds mirrorOffset to state
  @param {Object} state
  @param {SensorEvent} state.sensorEvent
  @param {DOMRect} state.sourceRect
  @return {Promise}
  @private