Draft: Add processing directives without namespace and with empty namespace

[cbravobernal]

POC after this conversation:
#5795 (comment)

cc: @felixarntz

Trac ticket:

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[github-actions]

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[felixarntz]

Can you clarify how this change fixes the problem? Difficult to understand from looking at the surrounding code, and it seems such a simple change. To be fair, I'm not very familiar with the underlying code :)

[gziolo]

How does this change impact accessing the context on the client?

[cbravobernal]

It should change the impact, rather than anyone can access namespaces not defined with this default one.

[cbravobernal]

Can you clarify how this change fixes the problem? Difficult to understand from looking at the surrounding code, and it seems such a simple change. To be fair, I'm not very familiar with the underlying code :)

The directives were not being processed cause they expected non empty string as a namespace. While reading the data-wp-interactive attribute, we are returning a boolean in case is not defined data-wp-interactive or an empty string.

Adding a default one would fix it (my tests are running OK in local, not here 🤔 ), but it is not a good solution. That's why I wanted to check with @DAreRodz too 😅

[luisherranz]

Hey @c4rl0sbr4v0, thanks for catching this and working on a fix 🙂

This bug is definitely my fault, but I don't think using WP is a proper solution and it would cause a divergence between how the server and client work, which will lead to other bugs.

The server directive processing should work without a default namespace. If this is failing because the functions/helpers are not expecting namespace to be null, we should fix that.

[cbravobernal]

Let's close this one and work on a proper solution.