title: Are nested catches within promises required?
body: <p>We would like to reduce the number of catch blocks inside our promises. If we remove the nested catches, will exceptions bubble up to the parent catch?</p>
  
  <pre><code>temporaryUserModel.findOne({email: req.body.email})
      .then(tempUser =&gt; {
          if (tempUser) {
              temporaryUserModel.findOneAndUpdate({_id: tempUser.toJSON()._id}, user)
                  .then((doc) =&gt; {
                      return res.status(200).json({
                          status: 'Success',
                          data: {url: planOpted.chargifySignupUrl}
                      });
                  })
                  .catch(err =&gt; error(err, res));
          } else {
              temporaryUserModel(user).save()
                  .then((doc) =&gt; {
                      return res.status(200).json({
                          status: 'Success',
                          data: {url: planOpted.chargifySignupUrl}
                      });
                  })
                  .catch(err =&gt; error(err, res));
          }
      })
      .catch(err =&gt; error(err, res));
  </code></pre>
  
  <p>We'd like to remove the two nested catches and keep only the catch at the bottom. Is this ok?</p>