shared/extendPromise

Classes

PromiseExtender

Methods

(inner) apply(target, thisArg, args) → {Promise}

Source:

This is a trap for when a function gets called (remember this gets used for then/ catch/finally); it processes the result using the oringinal function and since promise methods return a promise, instead of returning the original result, it returns an extended version of it.

Parameters:
Name Type Description
target function

The original function.
thisArg Promise

The promise the function belongs to.
args Array

The list of arguments sent to the trap.
Returns:
Type
Promise

(inner) extendPromise(promise, properties) → {Proxy.<Promise>}

Source:
Tutorials:

Extends a Promise by injecting custom properties using a Proxy. The custom properties will be available on the promise chain no matter how many thens, catchs or finallys are added.

Parameters:
Name Type Description
promise Promise

The promise to extend.
properties Object

A dictionary of custom properties to inject in the promise chain.
Throws:

  • If promise is not a valid instance of Promise.

    Type
    Error

  • If properties is not an object or if it doesn't have any properties.

    Type
    Error
Returns:
Type
Proxy.<Promise>

(inner) get(target, name) → {*}

Source:

This is a trap for when something is trying to read/access a property for the promise. The function first validates if it's one of the functions (then/catch/finally) in order to return a proxied function; then, if it's another function (one that doesn't return another promise), it just calls the original; finally, before doing a fallback to the original promise, it checks if it's one of the custom properties that exented the promise.

Parameters:
Name Type Description
target Promise

The original promise.
name string

The name of the property.
Returns:
Type
*