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'use strict';
/** * Creates an object that precomputes whether a given path has child fields in * the projection. * * #### Example: * *     const res = hasIncludedChildren({ 'a.b.c': 0 }); *     res.a; // 1 *     res['a.b']; // 1 *     res['a.b.c']; // 1 *     res['a.c']; // undefined * * @param {Object} fields * @api private */
module.exports = function hasIncludedChildren(fields) {  const hasIncludedChildren = {};  const keys = Object.keys(fields);
  for (const key of keys) {    if (key.indexOf('.') === -1) {      hasIncludedChildren[key] = 1;      continue;    }    const parts = key.split('.');    let c = parts[0];
    for (let i = 0; i < parts.length; ++i) {      hasIncludedChildren[c] = 1;      if (i + 1 < parts.length) {        c = c + '.' + parts[i + 1];      }    }  }
  return hasIncludedChildren;};