Klubok
Do notation pipes for Promise-based or pure functions which easy to mock
Inspired by fp-ts/Effect bind Do-notation, but much more small and simple
Primarly created for easy mocking of functions, which allows to write tons of unit tests using London school approach
Example
{ /* fetch cats from DB */ }),
pure('catsOneYearOld', ({ cats }) => cats.map(cat => ({ ...cat, age: cat.age + 1 })),
eff('saved', async ({ catsOneYearOld }) => { /* save to DB */ })
)
// production usage
catsBirthdays({ ids: [1, 2, 3] })
// in tests usage
catsBirthdays(
{ ids: [1, 2, 3] },
{
// DB response mock
cats: () => [
{ name: 'Barsik', age: 10 },
{ name: 'Marfa', age: 7 }
]
},
// call only this functions
['catsOneYearOld']
) // Promise<{ ..., catsOneYearOld: [{ name: 'Barsik', age: 11 }, { name: 'Marfa', age: 8 }] }>
">import { pure, eff, klubok } from 'klubok';
const catsBirthdays = klubok(
eff('cats', async ({ ids }: { ids: number[] }) => { /* fetch cats from DB */ }),
pure('catsOneYearOld', ({ cats }) => cats.map(cat => ({ ...cat, age: cat.age + 1 })),
eff('saved', async ({ catsOneYearOld }) => { /* save to DB */ })
)
// production usage
catsBirthdays({ ids: [1, 2, 3] })
// in tests usage
catsBirthdays(
{ ids: [1, 2, 3] },
{
// DB response mock
cats: () => [
{ name: 'Barsik', age: 10 },
{ name: 'Marfa', age: 7 }
]
},
// call only this functions
['catsOneYearOld']
) // Promise<{ ..., catsOneYearOld: [{ name: 'Barsik', age: 11 }, { name: 'Marfa', age: 8 }] }>
const catsBirthdays = klubok(
eff('cats', async ({ ids }: { ids: number[] }) => { /* fetch cats from DB */ }),
pure('catsOneYearOld', ({ cats }) => cats.map(cat => ({ ...cat, age: cat.age + 1 })),
eff('saved', async ({ catsOneYearOld }) => { /* save to DB */ })
)
// production usage
catsBirthdays({ ids: [1, 2, 3] })
// in tests usage
catsBirthdays(
{ ids: [1, 2, 3] },
{
// DB response mock
cats: () => [
{ name: 'Barsik', age: 10 },
{ name: 'Marfa', age: 7 }
]
},
// call only this functions
['catsOneYearOld']
) // Promise<{ ..., catsOneYearOld: [{ name: 'Barsik', age: 11 }, { name: 'Marfa', age: 8 }] }>
See also
- Klubok-Gleam - Gleam implementation of Klubok