Thanks for reporting this issue.

We have a linter that checks the validity of code examples ... so this should have been detected. @OskarStark do you know why this wasn't reported by the linter? Thanks!

If you mean DOCtor-RST it is only checking for valid XML structure, not the content. Not sure the code examples checker of @Nyholm provide such a feature 🤷

Code blocks checks is not active for xml. The main reason is that I had issues before and I haven’t come back to it.

symfony-tools/code-block-checker#17

symfony/symfony#46594 has been merged, and should at least partially fix the root of the problem.
Let me know if I can do something else to help moving forward on this XML stuff.

I'm closing this as fixed because of what @HeahDude said.

If I misunderstood and we still to merge this, please tell me and I'll reopen. Thanks!

The linked code change was not related to the serializer configuration and thus does not affect this here, does it?

Yeah the merged PR allows the checker to do its job, the fix was probably legit though.
A rebase or rerunning the CI would definitely help here.

For reference https://github.com/symfony/symfony/blob/6.2/src/Symfony/Component/Serializer/Mapping/Loader/schema/dic/serializer-mapping/serializer-mapping-1.0.xsd#L84.
So the fix is legit and should be merged.

I rebased and force-pushed this morning, but GitHub is asking me to create a new PR. Maybe it will show up if this is reopened — but I also don’t mind running the code checker locally and addressing any other XML issues more comprehensively as new pull requests, if necessary.

I cannot reopen 😐

Ultimately, it looks like there are a number of changes required across the code-checker utility and sample application to actually make it detect this invalid configuration.

First, the first line of the XML sample has to be a comment with the name of a config file that can be created in the sample app.

Secondly, the file path must begin with config/packages.

This doesn’t make sense for the Serializer, because its XML config files go in config/serializer. So the example config path would be config/serializer/App/Model/MyClass.xml. So XML serialization configuration files (and perhaps others?) are currently incompatible with the code checker.

I did create a file at that path in the sample app and even created an App\Model\MyClass class with a $bar property, but cache:warm still wouldn’t register an error — so there may be further required changes to the sample app, but I just gave up at that point. 😅

In light of this, I recreated this PR as #17327.