Seed Generators

FuzzSeed provides deterministic helpers for building inputs from a base seed.

Available Helpers

• seed.boolean()
• seed.pick(values)
• seed.i32({ min, max, exclude })
• seed.u32({ min, max, exclude })
• seed.f32({ min, max, exclude })
• seed.f64({ min, max, exclude })
• seed.bytes({ min, max, include, exclude })
• seed.buffer({ min, max, include, exclude })
• seed.string({ charset, min, max, include, exclude, prefix, suffix })
• seed.array((seed) => value, { min, max })

String Charsets

Supported seed.string(...) charsets:

• ascii
• alpha
• alnum
• digit
• hex
• base64
• identifier
• whitespace
• custom

Example

fuzz("ascii identifiers stay non-empty", (value: string): bool => {
  return value.length > 0;
}).generate((seed: FuzzSeed, run: (value: string) => bool): void => {
  run(
    seed.string({
      charset: "identifier",
      min: 1,
      max: 16,
    }),
  );
});