Promise.then not executing

Question

In the following code block only 'first promise' is logged to console. Why is that? I was trying to write a test to figure out how .then()'s execute after .catch() but was surprised when nothing besides the first promise ran. Whats going on here?

   function foo() {
      return new Promise((resolve, reject) => {
        return console.log('first promise')
      })
      .then(() => console.log('first then'))
      .catch(() => console.log('catch block'))
      .then(() => console.log('last block'))
      .then(() => resolve)
    }
    foo();

Answer 1

As Yury said, you're not resolving the promise, simply returning a log.

https://jsfiddle.net/k7gL57t3/

 function foo() {
   var p1 = new Promise((resolve, reject) => {
     resolve("Test");
   })
   p1.then(() => console.log('first then'))
     .then(() => console.log('last block'))
     .then(() => resolve)
     .catch(() => console.log('catch block'));
 }
foo();

Answer 2

I believe it's because your then chain does not have closure to resolve inside of the Promise callback. Try this:

function foo() {
    return Promise.resolve()
        .then(() => console.log('first then'))
        .catch(() => console.log('catch block'))
        .then(() => console.log('last block'));
}

or this if you want to use the Promise constructor:

function foo() {
    return new Promise((resolve, reject) => {
        console.log('first promise');
        return resolve();
    })
        .then(() => console.log('first then'))
        .catch(() => console.log('catch block'))
        .then(() => console.log('last block'));
}