v-mask/src/utils/extendMaskReplacers.js

Tiny input mask library for Vue.js based on text-mask-core (~5kb) exposed as directive. No dependencies

import { defaultMaskReplacers } from '../constants';

/**
 * Merge custom mask replacers with default mask replacers
 * @param {MaskReplaces} maskReplacers
 * @param {MaskReplaces} baseMaskReplacers
 * @return {MaskReplaces} The extended mask replacers
 */
function extendMaskReplacers(maskReplacers, baseMaskReplacers = defaultMaskReplacers) {
  if (maskReplacers === null || Array.isArray(maskReplacers) || typeof maskReplacers !== 'object') {
    return baseMaskReplacers;
  }

  return Object.keys(maskReplacers).reduce((extendedMaskReplacers, key) => {
    const value = maskReplacers[key];

    if (value !== null && !(value instanceof RegExp)) {
      return extendedMaskReplacers;
    }

    return { ...extendedMaskReplacers, [key]: value };
  }, baseMaskReplacers);
}

export default extendMaskReplacers;