mingo/esm/operators/update/pull.js

MongoDB query language for in-memory objects

import { Query } from "../../query";
import { isArray, isObject, isOperator } from "../../util";
import { applyUpdate, DEFAULT_OPTIONS, walkExpression } from "./_internal";
function $pull(expr, arrayFilters = [], options = DEFAULT_OPTIONS) {
  const predicates = Object.values(expr).map((pullSpec) => {
    const wrap = !isObject(pullSpec) || Object.keys(pullSpec).some(isOperator);
    const query = new Query(wrap ? { k: pullSpec } : pullSpec, options);
    return wrap ? (v) => query.test({ k: v }) : (v) => query.test(v);
  });
  return (obj) => {
    let index = 0;
    return walkExpression(expr, arrayFilters, options, (_, node, queries) => {
      const pred = predicates[index++];
      return applyUpdate(obj, node, queries, (o, k) => {
        const prev = o[k];
        if (!isArray(prev) || !prev.length) return false;
        const curr = new Array();
        let ok = false;
        for (const v of prev) {
          const b = pred(v);
          if (!b) curr.push(v);
          ok ||= b;
        }
        if (!ok) return false;
        o[k] = curr;
        return true;
      });
    });
  };
}
export {
  $pull
};