/**

 * Copyright (c) Meta Platforms, Inc. and affiliates.

 *

 * This source code is licensed under the MIT license found in the

 * LICENSE file in the root directory of this source tree.

 *

 * @flow

 */

/**

 * @param {array} arr an "accumulation" of items which is either an Array or

 * a single item. Useful when paired with the `accumulate` module. This is a

 * simple utility that allows us to reason about a collection of items, but

 * handling the case when there is exactly one item (and we do not need to

 * allocate an array).

 * @param {function} cb Callback invoked with each element or a collection.

 * @param {?} [scope] Scope used as `this` in a callback.

 */

function forEachAccumulated<T>(

  arr: ?(Array<T> | T),

  cb: (elem: T) => void,

  scope: ?any,

) {

  if (Array.isArray(arr)) {

    // $FlowFixMe[incompatible-call] if `T` is an array, `cb` cannot be called

    arr.forEach(cb, scope);

  } else if (arr) {

    cb.call(scope, arr);

  }

}

export default forEachAccumulated;