ioredis-mock-with-info/lib/commands/getbit.js

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

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.getbit = getbit;
var MAX_OFFSET = Math.pow(2, 32) - 1;

function getbit(key, offset) {
  if (offset > MAX_OFFSET) throw new Error('ERR bit offset is not an integer or out of range');
  if (!this.data.has(key)) return 0;
  var current = this.data.get(key);
  if (offset > current.length * 8) return 0;

  var byteOffset = parseInt(offset / 8, 10);
  var shift = 7 - offset % 8; // redis store bit in reverse order (left to right)
  // eslint-disable-next-line no-bitwise
  return current.charCodeAt(byteOffset) >> shift & 1;
}