MZanggl / taptaptap

Turn non fluent apis into fluent ones

Turns non fluent APIs into fluent APIs

npm install taptaptap

Examples

Take Array.prototype.push for example. It returns the new length of the array, making chaining impossible.

const numbers = []
numbers.push(1)
numbers.push(2)

Wrapping the array inside "tap" allows us to chain everything together nicely.

const { tap } = require('taptaptap')

const numbers = tap([])
    .push(1)
    .push(2)

tap uses ES6 proxies to make sure each function gets executed, but returns the initially passed value (in this case, the numbers array).

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One more example using classes

class User {
    name = null
    setName(name) {
        this.name = name
    }
    
    getId() {
        return this.id
    }

    save() {
        // persist data

        this.id = this.createUUID() // fill it with new id
        this.createdAt = new Date()

        return true // if everything went well
    }
}

The way the API was built forces us to access it like this.

function createUser(name) {
    const user = new User
    
    user.setName(name)
    user.save()

    return user
}

Using tap we can do

const { tap } = require('taptaptap')

function createUser(name) {
    return tap(new User)
        .setName(name)
        .save()
}

or using an arrow function

const { tap } = require('taptaptap')

const createUser = name => tap(new User).setName(name).save()

Getting values

Since every function just executes the initial value again, you either have to break out of the chain, or tap out of it.

const { tap } = require('taptaptap')

function createUserAndGetId(name) {
    return tap(new User)
        .setName(name)
        .save()
        .tapOut
        .getId()
}

---

Alternatively, you can also pass a function in the second argument to group common logic.

Turning

const user = User.query().latest().first()

expect(user.name).toBe('test name')
expect(user.bio).toBe('test bio')

to

tap(User.query().latest().first(), user => {
    expect(user.name).toBe('test name')
    expect(user.bio).toBe('test bio')
})