Tcomb-generate NPM

tcomb-generate

tcomb-generate convert tcomb type to jsverify arbitrary.

Background

Property-based testing is very awesome approach for analyze and verification program. But this approach requires the writing of generators for all datatypes in our program. This process is very time-consuming, error-prone and not DRY.

Example:

import * as t from 'tcomb'

const AsteroidType = t.interface({
    type: t.enums.of('asteroid'),
    location: t.tuple([t.Number, t.Number, t.Number]),
    mass: t.Number,
})

const AsteroidArbitrary = jsc.record({
    type: jsc.constant('asteroid'),
    location: jsc.tuple(jsc.number, jsc.number, jsc.number),
    mass: jsc.number
})

But with tcomb-generate we can get AsteroidArbitrary from AsteroidType:

import { makeJsverifyArbitrary } from 'tcomb-generate'
const AsteroidType = t.interface({
    type: t.enums.of('asteroid'),
    location: t.tuple([t.Number, t.Number, t.Number]),
    mass: t.Number,
})
const AsteroidArbitrary = makeJsverifyArbitrary(AsteroidType)

Install

npm install --save tcomb-generate

Usage

API

makeJsverifyArbitrary(type: Type<any>): jsc.Arbitrary<any> - convert tcomb type to jsverify arbitrary
addTypeToRegistry(name: string, (x: Type<any>) => jsc.Arbitrary<any>): void - add new generator for type with name
addTypeToIntersectRegistry(names: string[], generator: (x: Type<any>) => jsc.Arbitrary<any>): void) - add new generator for custom t.intersection types. TODO example
generateAndCheck(rt: Type<any>, opts?: jsc.Options): () => void - run jsc.assert for property type.is(generatedData) for all generatedData obtained from makeJsverifyArbitrary(type). Uses for verification custom generators for custom named type. See example in tests.