ioredis-mock/lib/commands/lrange.js

This library emulates ioredis by performing all operations in-memory.

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.lrange = lrange;
/**
 * Returns the specified elements of the list stored at key. The offsets start and stop are zero-based indexes, with 0 being the first element of the list (the head of the list), 1 being the next element and so on.
 * These offsets can also be negative numbers indicating offsets starting at the end of the list. For example, -1 is the last element of the list, -2 the penultimate, and so on.
 *
 * @param {string} key
 * @param {string} start Start index
 * @param {string} end End index (included in returned range)
 * @return {Array} An array in the defined range
 */
function lrange(key, s, e) {
  if (this.data.has(key) && !(this.data.get(key) instanceof Array)) {
    throw new Error("Key " + key + " does not contain a list");
  }
  var start = parseInt(s, 10);
  var end = parseInt(e, 10);

  var list = this.data.get(key) || [];

  if (start < 0) {
    start = list.length + start;
  }
  if (end < 0) {
    end = list.length + end;
  }

  return list.slice(start, end + 1);
}