Promise.all is returning an array of undefined and resolves before being done

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Promise.all accepts an Array of Promise objects.
You’re getting an Array of undefined because you’re not returning any Promise in your map callback:

function addText(queries) {
  return Promise.all(queries.map(function(query) {
    // Add `return` here or the `map` returns an Array of `undefined`.
    return models.queries
      .findById(query.queryId, {
        raw: true,
        attributes: [ "query" ]
      })
      .then(function(queryFetched) {
        query.text = queryFetched.query;
        console.log(query);
        
        return Promise.resolve(query);
      }, function(error) {
        return Promise.reject(error);
      });
  }));
};

A primitive value such as undefined will resolve immediately in Promise.all, therefore it resolves before any of the Promises in your callback resolve.

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