Tests: Cover how wp_prepare_json_schema_for_client() encodes defaults

[gziolo]

What?

Adds a test for how wp_prepare_json_schema_for_client() handles the default of a schema. It uses a data provider with three cases:

• An empty default on an object schema is encoded as {}.
• A non-empty default on an object schema stays the same.
• An empty default on an array schema stays [].

Why?

In PHP, an empty array is encoded as [] in JSON. For an object schema, clients expect {}. The helper already fixes this, but only a nested property was tested before, not the root schema.

Abilities rely on this. They can use 'default' => array() in an object input schema, and both the REST API and the AI client still send {}. This came up in #12141.

Testing

npm run test:php -- --filter test_wp_prepare_json_schema_for_client_encodes_default

Trac ticket: https://core.trac.wordpress.org/ticket/64955

Use of AI Tools

The test and this description were drafted with Claude Code and reviewed by me.

🤖 Generated with Claude Code

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Props gziolo.

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