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'use strict';
const hasDollarKeys = require('./hasDollarKeys');const { trustedSymbol } = require('./trusted');
module.exports = function sanitizeFilter(filter) {  if (filter == null || typeof filter !== 'object') {    return filter;  }  if (Array.isArray(filter)) {    for (const subfilter of filter) {      sanitizeFilter(subfilter);    }    return filter;  }
  const filterKeys = Object.keys(filter);  for (const key of filterKeys) {    const value = filter[key];    if (value != null && value[trustedSymbol]) {      continue;    }    if (key === '$and' || key === '$or') {      sanitizeFilter(value);      continue;    }
    if (hasDollarKeys(value)) {      const keys = Object.keys(value);      if (keys.length === 1 && keys[0] === '$eq') {        continue;      }      filter[key] = { $eq: filter[key] };    }  }
  return filter;};