Generated typescript migrations and seeds have type errors

[nhjk]

Environment

Knex version: 0.15.2

Bug

1. Explain what kind of behaviour you are getting and how you think it should do

Getting type errors, shouldn't have any.

2. Error message

Type 'Bluebird<any>' is not assignable to type 'Promise<any>'.
  Property '[Symbol.toStringTag]' is missing in type 'Bluebird<any>'.

This is because the bluebird promise type is incompatible with the typescript Promise type. This can fixed by simply wrapping the function body in Promise.resolve(...) and returning that instead.

Example (seed file, needs to be fixed with migration as well)

Current generated code

import * as Knex from "knex";

exports.seed = function (knex: Knex): Promise<any> {
    // Deletes ALL existing entries
    return knex("table_name").del()
        .then(function () {
            // Inserts seed entries
            return knex("table_name").insert([
                { id: 1, colName: "rowValue1" },
                { id: 2, colName: "rowValue2" },
                { id: 3, colName: "rowValue3" }
            ]);
        });
};

Code that typechecks correctly by adding Promise.resolve(...)

import * as Knex from "knex";

exports.seed = function(knex: Knex): Promise<any> {
  // Deletes ALL existing entries
  return Promise.resolve( // <-- added line
    knex("table_name")
      .del()
      .then(function() {
        // Inserts seed entries
        return knex("table_name").insert([
          { id: 1, colName: "rowValue1" },
          { id: 2, colName: "rowValue2" },
          { id: 3, colName: "rowValue3" }
        ]);
      })
  );
};

[elhigu]

Wouldnt it be better to declare function as async?

exports.seed = async function(knex: Knex): Promise<any> {
  //...
};

[nhjk]

Yes that's what I started doing shortly after filing the issue, should have updated it.

[JakeGinnivan]

Could also use PromiseLike

ie

import * as Knex from "knex";

exports.seed = function (knex: Knex): PromiseLike<any> {
    // Deletes ALL existing entries
    return knex("table_name").del()
        .then(function () {
            // Inserts seed entries
            return knex("table_name").insert([
                { id: 1, colName: "rowValue1" },
                { id: 2, colName: "rowValue2" },
                { id: 3, colName: "rowValue3" }
            ]);
        });
};

[elhigu]

Fixed #2816

[meghna2109]

(function (exports, require, module, __filename, __dirname) { import ...
getting error - on import statement.