Promise.reject() continues with then() instead of catch()

Question

I am making myself a library which retries failed promise "chain-parts" - I collect methods to be called and queue next phase only after previous succeeded.

Conceptually rounded up - my problems are more fundamental. This is where I arrived with debugging:

this.runningPromise
    .then(function() { 
        return Promise.reject();
    })
//;
//this.runningPromise
    .then(this.promiseResolver.bind(this))
    .catch(this.promiseRejector.bind(this))
    ;

Works, promiseRejector kicks in. When I uncomment out the two lines, works not. promiseResolver gets called.

Can't find anywhere anything. Nodejs 6.10.3 with browserify on Windows, Chrome.

Answer 1

If you uncomment two rows means you are calling this.runningPromise twice and each time it has its own callbacks.

If you keep the rows commented then it will act as a promise (and associated callbacks)

Better you should assign promise to a variable and then you can use it multiple times.

let newPromise = this.runningPromise
    .then(function() { 
        return Promise.reject();
    });

newPromise
    .then(this.promiseResolver.bind(this))
    .catch(this.promiseRejector.bind(this));

With above code you can use newPromise multiple times.