@observ33r/object-generator NPM

object-generator

High-performance, customizable dummy object generator for testing and benchmarking.

Features

Guaranteed Structure Consistency
The nestedSize and depth options are always respected, ensuring consistent object structures even when circular references are enabled with circular: true. This guarantees predictable output regardless of configuration.
Globally Unique Identifiers
With globalIndex: true, all keys and string values remain unique across the generated object. This uniqueness eliminates ambiguity and ensures reliable comparisons or traversals.
Real-World Object Design
Objects are crafted to mimic real-world data structures as closely as possible. This approach avoids overly simplistic or uniform patterns that could trigger JIT (Just-In-Time) compiler optimizations, making the generator ideal for robust benchmarking and testing scenarios.
Performance Testing Ready
Designed for benchmark challenges between libraries by providing diverse and repeatable complex objects!
Type-Safe
Fully typed with TypeScript declarations.

Installation

Install the package via npm:

npm install @observ33r/object-generator`

Usage

`objectGenerator([options])`

options: Optional configuration object (see below).
Returns: Object | Array | Set | Map | Uint8Array - An object of the specified type with generated content based on the provided options.

Options

Property	Type	Default	Description
prefix	`string \\| number \\| false`	`false`	A prefix to prepend to generated keys/strings. Must be a non-empty string, number or `false`.
type	`constructor`	`Object`	The type of object to generate. Must be one of `Object`, `Array`, `Set`, `Map`, or `Uint8Array`.
size	`number`	`16`	Size of the top-level object. Must be an integer.
nestedSize	`number`	`16`	Size of nested objects. Must be an integer.
depth	`number`	`0`	Maximum depth for nested structures. Must be an integer.
valueTypes	`[constructor \\| NaN \\| undefined \\| null]`	`[String]`	Types of values to include: `Boolean`, `Number`, `String`, `Date`, `RegExp`, `Uint8Array`, `Object`, `Array`, `Set`, `Map`, `NaN`, `undefined`, `null`.
globalIndex	`boolean`	`true`	Whether to include a global index in generated keys/values.
circular	`boolean`	`false`	Whether to allow circular references in the generated object.
shuffle	`boolean`	`false`	Whether to shuffle the order of elements or keys.
seed	`number`	random	Seed for randomization when `shuffle` is enabled. If not provided, a random seed is used.

Examples

Generate a simple Object

import { objectGenerator } from '@observ33r/object-generator';

const obj = objectGenerator({ size: 4 });

console.log(obj);

{
  'string-4-0': 'value-4-0',
  'string-4-1': 'value-4-1',
  'string-4-2': 'value-4-2',
  'string-4-3': 'value-4-3'
}

Generate a nested Object with a prefix

import { objectGenerator } from '@observ33r/object-generator';

const obj = objectGenerator({
  prefix: 'data',
  size: 4,
  nestedSize: 4,
  depth: 1,
  valueTypes: [String, Number, Boolean]
});

console.log(obj);

{
  'data-string-4-0-0-0': 'data-value-4-0-0-0',
  'data-number-4-0-1-1': 1,
  'data-boolean-4-0-2-2': true,
  'data-object-4-0-3-3': {
    'data-string-4-1-4-0': 'data-value-4-1-4-0',
    'data-number-4-1-5-1': 1,
    'data-boolean-4-1-6-2': true,
    'data-string-4-1-7-3': 'data-value-4-1-7-3'
  }
}

Generate a simple numeric Array

import { objectGenerator } from '@observ33r/object-generator';

const arr = objectGenerator({
  type: Array,
  size: 8,
  valueTypes: [Number],
});

console.log(arr);

[
  0, 1, 2, 3,
  4, 5, 6, 7
]

Generate a repeatable shuffled Typed Array

import { objectGenerator } from '@observ33r/object-generator';

const typedArray = objectGenerator({
  type: Uint8Array,
  size: 8,
  shuffle: true,
  seed: 42
});

//Uint8Array
console.log(typedArray);
//or ArrayBuffer
console.log(typedArray.buffer);
//or DataView
console.log(new DataView(typedArray.buffer));

Uint8Array(8) [
  2, 0, 4, 1,
  3, 6, 7, 5
]

ArrayBuffer {
  [Uint8Contents]: <02 00 04 01 03 06 07 05>,
  byteLength: 8
}

DataView {
  byteLength: 8,
  byteOffset: 0,
  buffer: ArrayBuffer {
    [Uint8Contents]: <02 00 04 01 03 06 07 05>,
    byteLength: 8
  }
}

Generate a repeatable shuffled nested Set without a global index

import { objectGenerator } from '@observ33r/object-generator';

const set = objectGenerator({
  type: Set,
  size: 2,
  nestedSize: 2,
  depth: 2,
  valueTypes: [Set],
  globalIndex: false,
  shuffle: true,
  seed: 42
});

console.log(set);

Set(2) {
  Set(2) {
    Set(2) { 'value-2-2-1', 'value-2-2-0' },
    Set(2) { 'value-2-2-0', 'value-2-2-1' }
  },
  Set(2) {
    Set(2) { 'value-2-2-0', 'value-2-2-1' },
    Set(2) { 'value-2-2-1', 'value-2-2-0' }
  }
}