[dhrupo]

Trac ticket: https://core.trac.wordpress.org/ticket/66644

Summary

WP_REST_Blocks_Controller removes title.rendered and content.rendered from the synced pattern schema, because a block only renders in the context of a post or a page — but WP_REST_Posts_Controller::prepare_item_for_response() still ran get_the_title() and apply_filters( 'the_content' ) on every pattern REST response, and filter_response_by_context() then discarded the results. With hooks on the_content, every pattern fetch in the site editor pays for a full render that is thrown away.

Fix

Only run the title and content rendering passes when the controller's schema actually contains the rendered property. Controllers that keep the property — posts, pages, attachments, revisions, templates — take the exact same code path as before; the guards only skip work whose result the response would discard.

Testing

New test REST_Blocks_Controller_Test::test_rendered_fields_are_not_rendered() registers counters on the_content and the_title, fetches a synced pattern over REST, and asserts neither filter ran.

• Before: fails — the_content runs once for the discarded content.rendered.
• After: passes; the full REST API suite is green.

vendor/bin/phpunit --group restapi → 4025 tests, 0 failures. vendor/bin/phpunit -c tests/phpunit/multisite.xml --group restapi-blocks → OK.

Use of AI Tools

AI assistance: Kimi (Moonshot AI) drafted the patch and the test; I reviewed every change, reproduced the issue on trunk, and ran and verified all results myself.

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