Fix issues with extending {XML,Yaml} -> {XML,Yaml} resources

[senghe]

Q	A
Branch?	3.2
Tickets
License	MIT
Doc PR

Hi all! :) I was testing a feature of extending resources by multiple XML/Yaml resource files for the same resource. For XMLs it works from scratch, but there is two issues:

• First, when trying to extend Yaml configuration by another Yaml configuration
• Second, when trying to extend Yaml configuration by XML, and when trying to extend XML by Yaml.

It looks for me as a bug, because as you can see, there is too little changes from me to solve it.

Please let me know, what is your opinion regarding to this topic :vulcan_salute:

[senghe]

I see one build run has been cancelled - the red one. Could you rerun it? :pray:

[soyuka]

this looks nice, can you target 3.1? We should add a test somehow

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[senghe]

Hi, to be honest I'm not so familiar with API Platform dev structure, so I think I'm not able to add tests here. But in a free time I'll check whether the index is always integer - as it was discussed above and refactor this.