mingo/esm/operators/update/pop.js

MongoDB query language for in-memory objects

import { assert, isArray } from "../../util";
import { applyUpdate, DEFAULT_OPTIONS, walkExpression } from "./_internal";
const $pop = (obj, expr, arrayFilters = [], options = DEFAULT_OPTIONS) => {
  return walkExpression(
    expr,
    arrayFilters,
    options,
    (val, node, queries) => {
      return applyUpdate(obj, node, queries, (o, k) => {
        const arr = o[k];
        assert(
          isArray(arr),
          `path '${node.selector}' contains an element of non-array type.`
        );
        if (!arr.length) return false;
        if (val === -1) {
          arr.splice(0, 1);
        } else {
          arr.pop();
        }
        return true;
      });
    }
  );
};
export {
  $pop
};