SpoofSettings Overview

SpoofSettings is the single optional argument of Forger.create and Forger.createWith. It tunes how numbers, strings, dates, and arrays are generated. Anything omitted falls back to the default.

Usage

const user = Forger.create<User>({
  numberMax: 100,       // numbers stay small
  stringLength: 8,      // shorter strings
  arrayLength: 5,       // bigger arrays
  dateMin: new Date(2024, 0, 1),
});

Settings are merged with the defaults per call, so a settings object with a single key is perfectly fine — the rest keeps default behavior. The object may be inline, a variable, or the result of a function call.

Full reference

Option	Type	Default	Affects	Details
`numberMin`	`number`	`1`	Lower bound of numbers, inclusive	Numbers
`numberMax`	`number`	`1000`	Upper bound of numbers, inclusive	Numbers
`numberFloat`	`boolean`	`false`	Fractional instead of integer numbers	Numbers
`stringLength`	`number`	`10`	Length of generated strings	Strings
`stringNumbers`	`boolean`	`true`	Digits in the string charset	Strings
`stringLowCase`	`boolean`	`true`	Lowercase letters in the charset	Strings
`stringUpCase`	`boolean`	`true`	Uppercase letters in the charset	Strings
`stringSpecial`	`boolean`	`true`	Special characters in the charset	Strings
`dateMin`	`Date` or `string`	`2000-01-01`	Lower bound of dates, inclusive	Dates
`dateMax`	`Date` or `string`	`4000-01-01`	Upper bound of dates, inclusive	Dates
`arrayLength`	`number`	`3`	Length of generated arrays	Arrays

Scope

Settings apply per call and flow into every nested level — a numberMax: 10 limits all numbers in the whole object graph, and arrayLength sizes arrays at every depth.

interface Metric { value: number; history: number[] }

const metric = Forger.create<Metric>({ numberMax: 10, arrayLength: 5 })!;
// { value: ≤ 10, history: 5 numbers, each ≤ 10 }

Booleans, enums, literal unions, tuples, and circular depth are not affected by settings — their behavior is defined by the type itself.

Type definition

The class behind the settings with all defaults spelled out is documented in API Reference: SpoofSettings.

08 September 2026