mingo/esm/operators/accumulator/accumulator.js

MongoDB query language for in-memory objects

import { ComputeOptions, computeValue } from "../../core/_internal";
import { assert } from "../../util";
import { $push } from "./push";
const $accumulator = (collection, expr, options) => {
  assert(
    options.scriptEnabled,
    "$accumulator requires 'scriptEnabled' option to be true"
  );
  const copts = ComputeOptions.init(options);
  const initArgs = computeValue(
    copts?.local?.groupId,
    expr.initArgs || [],
    null,
    copts.update({ root: copts?.local?.groupId })
  );
  const args = $push(collection, expr.accumulateArgs, copts);
  args.forEach((arr) => arr.forEach((v, i) => arr[i] = v ?? null));
  const initialValue = expr.init.apply(null, initArgs);
  const result = args.reduce(
    (acc, v) => expr.accumulate.apply(null, [acc, ...v]),
    initialValue
  );
  return expr.finalize ? expr.finalize.call(null, result) : result;
};
export {
  $accumulator
};