https://github.com/giogonzo/fast-check-io-ts

io-ts codec to fast-check arbitrary mapping
https://github.com/giogonzo/fast-check-io-ts

Last synced: 21 days ago
JSON representation

io-ts codec to fast-check arbitrary mapping

• Host: GitHub
• URL: https://github.com/giogonzo/fast-check-io-ts
• Owner: giogonzo
• Created: 2019-08-06T13:58:22.000Z (over 5 years ago)
• Default Branch: master
• Last Pushed: 2021-08-31T10:21:14.000Z (about 3 years ago)
• Last Synced: 2024-10-11T22:51:16.097Z (about 1 month ago)
• Language: TypeScript
• Size: 14.6 KB
• Stars: 32
• Watchers: 1
• Forks: 2
• Open Issues: 1
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

README

        
# fast-check-io-ts

[io-ts](https://github.com/gcanti/io-ts) codecs mapped to [fast-check](https://github.com/dubzzz/fast-check) arbitraries.

## Usage

```ts

import * as fc from 'fast-check';

import * as t from 'io-ts';

import { getArbitrary } from 'fast-check-io-ts';

const NonEmptyString = t.brand(

  t.string,

  (s): s is t.Branded => s.length > 0,

  'NonEmptyString'

);

const User = t.type({

  name: t.string,

  status: t.union([t.literal('active'), t.literal('inactive')]),

  handle: NonEmptyString

});

const userArb = getArbitrary(User);

console.log(fc.sample(userArb, 1)[0]); // { name: '', status: 'inactive', handle: 'M.y?>A/' }

```

## Known issues

- only supports predefined `io-ts` codecs, not custom types e.g. `DateFromISOString` from `io-ts-types`

- `getArbitrary(t.keyof({ ... }))` is currently marked as error by TS, even though the codec is supported in the implementation