Function _addGrace

src/helpers/helpers.options.ts:186–194

(minmax: { min: number; max: number; }, grace: number | string, beginAtZero: boolean)

 * @private
 */
export function _addGrace(minmax: { min: number; max: number; }, grace: number | string, beginAtZero: boolean) {
  const {min, max} = minmax;
  const change = toDimension(grace, (max - min) / 2);
  const keepZero = (value: number, add: number) => beginAtZero && value === 0 ? 0 : value + add;
  return {
    min: keepZero(min, -Math.abs(change)),
    max: keepZero(max, change)
  };
}

/**
 * Create a context inheriting parentContext