The method chunkBy is not yielding chunks correctly

[verzola]

Bug Report

Information	Description
Version	9.15.0
PHP version	8.1
OS Platform	Ubuntu (WSL)

Summary

The recently added chunkBy method is not chunking the CSV correctly like it is described on the documentation:

If you are dealing with a large CSV and you want it to be split in smaller sizes for better handling you can use the chunkBy method which breaks the TabularDataReader into multiple, smaller instances with a given size. The last instance may contain fewer records because of the chunk size you have chosen.

Instead of creating chunks of the size passed to the chunkBy method, it only creates 2 chunks, the first one with the correct chunk size and the second and last with the total csv lines count.

It seems that this issue might be caused by the changes of this commit:
51968b6#diff-63e150e70c3f2253f8ab94c5a8fe06190bbfee264c842f2c7fb51f9920dd0f2eR170

I tested the first version of the chunkBy method from this commit and it is working as expected:
60b0062#diff-63e150e70c3f2253f8ab94c5a8fe06190bbfee264c842f2c7fb51f9920dd0f2eR170

If I add these 2 lines after the first yield in chunkBy method on the released 9.15.0 version, it also works as expected:

$nbRecords = 0;
$records = [];

Standalone code, or other way to reproduce the problem

I created a repository for this example:
https://github.com/verzola/league-csv-chunkby-bug

<?php

use League\Csv\Reader;

require_once __DIR__ . '/vendor/autoload.php';

// data.csv is an example csv with 6000 lines
$reader = Reader::createFromPath(__DIR__ . '/data.csv');

$chunks = $reader->chunkBy(1000);

foreach ($chunks as $chunk) {
  echo count($chunk) . PHP_EOL;
}

Expected result

The expected output is:
1000
1000
1000
1000
1000
1000

Actual result

The actual output is:
1000
6000

Checks before submitting

• Be sure that there isn't already an issue about this. See: Issues list
• Be sure that there isn't already a pull request about this. See: Pull requests
• I have added every step to reproduce the bug.
• If possible I added relevant code examples.
• This issue is about 1 bug and nothing more.
• The issue has a descriptive title. For example: "JSON rendering failed on Windows for filenames with space".

[nyamsprod]

thanks for reporting the issue it has been fixed and will be part of the next release.

[nyamsprod]

the fix is now released in version 9.16.0