feat: replace bluebird Promise with native Promise

[cyrdam]

Fix: #157

[simonh1000]

Could you implement this as a reduce please, then you won't need a global (within this fnction) variable

[a-tonchev]

I think this way is also ok, it is more clear than reduce

[cyrdam]

I don't have anything against a reduce version. One thing makes me curious in this case: how it performs in cases of many items in the array. reduce is not the best in performance for loops, but I didn't want to go for the for-loop version. 😄

I tried to make it a little bit more readable than reduce, just like @a-tonchev mentioned.

Anyway, here is a suggestion code for the function:

function mapSeries(array, mapper) {
    // Use the reduce method to chain promises together
    return array.reduce((promise, item, index) => {
        // For each item in the array, add a new promise to the chain
        return promise.then(output => {
            // Apply the mapper function to the current item
            return mapper(item, index, array).then(res => {
                // Push the result of the mapper function to the output array
                output.push(res);
                // Return the output array for the next iteration
                return output;
            });
        });
    // Start with a resolved promise and an empty array
    }, Promise.resolve([]));
}

It needs more comments to understand what exactly is done.

[a-tonchev]

@cyrdam one more thing - since bluebird is no more used, you can remove it from the package.json, so that we don't install not needed library there

[cyrdam]

It is already removed: https://github.com/simonh1000/ftp-deploy/pull/167/files#diff-7ae45ad102eab3b6d7e7896acd08c427a9b25b346470d7bc6507b6481575d519

[cyrdam]

@simonh1000 do you want to have the mentioned version, or the current implementation from the PR?

[simonh1000]

Ok, I've read about the reduce perf concerns. they probably don't apply at the scale of an ftp repo (and anyone with a very large directory would probably want the - as yet unimplemented - feature of upload only new files). But your map approach is not a deal breaker, so thank you for your efforts

[simonh1000]

see comment about using a reduce

[simonh1000]

👍

[simonh1000]

Ok, I've read about the reduce perf concerns. they probably don't apply at the scale of an ftp repo (and anyone with a very large directory would probably want the - as yet unimplemented - feature of upload only new files). But your map approach is not a deal breaker, so thank you for your efforts