Add description why php functions marked as discouraged and give alternatives

[ihor-sviziev]

Preconditions

N/A

Steps to reproduce

1. Make PR to Magento with changed file, that don't have like about ignoring discouraged pathinfo function or run magneto coding standard against some file.

Expected result

1. You should get understandable message what's wrong with your code, message The use of function pathinfo() is discouraged isn't clean enough
2. For case when some function marked as discouraged - there should be some information that shows reason of it, what is best practice
3. That's actually relevant for all rules

Good example: https://github.com/extdn/extdn-phpcs/blob/master/Extdn/Sniffs/Classes/StrictTypesSniff.md

Actual result

1. I'm getting result like this:
   Errors is quite clear, but not warnings

PHP Code Sniffer detected 2 violation(s): 

FILE: /var/www/html/app/code/Magento/Deploy/Service/DeployPackage.php
----------------------------------------------------------------------
FOUND 2 ERRORS AND 2 WARNINGS AFFECTING 4 LINES
----------------------------------------------------------------------
 109 | ERROR   | [x] Missing short description
 110 | ERROR   | [x] There must be exactly one blank line before tags
 224 | WARNING | [ ] The use of function pathinfo() is discouraged
 225 | WARNING | [ ] The use of function pathinfo() is discouraged
----------------------------------------------------------------------
PHPCBF CAN FIX THE 2 MARKED SNIFF VIOLATIONS AUTOMATICALLY
----------------------------------------------------------------------



Failed asserting that 2 matches expected 0.

Related question on stack overflow, answer not seems to me correct.
https://magento.stackexchange.com/questions/192978/the-use-of-function-pathinfo-is-discouraged-magento-2

[gixid192]

Totally agree. I wanted to follow the rules but sometimes it's hard to find an alternative function.

Usually, my approach is searching for that function in the whole vendor/magento folder, see if the Core team use it else where in the code. If I can't find it, I got stuck.

I also know that some are just warning, it is there to help developers mind the usage of the function, for example base64_decode, there is no wrapper, but it is safe to use with trusted input.
But the help with a suggestion will save developers time finding, say, in this case, the pathinfo can be found here https://github.com/magento/magento2/blob/2.3-develop/lib/internal/Magento/Framework/Filesystem/Io/File.php#L890

[diazwatson]

You can use Magento\Framework\Filesystem\Io\File which has a wrapper for that function.

Example:
https://magento.stackexchange.com/questions/192978/the-use-of-function-pathinfo-is-discouraged-magento-2/284317#284317