Add the content write abilities through the REST API

[jorgefilipecosta]

What?

Adds core/content-create, core/content-update and core/content-delete, the write counterparts to core/content-query. They have one implementation: the REST posts endpoint.

Stacked on #931 — it added the REST-backed read implementations, and this reuses that machinery.

Why?

The write paths are where the checks matter: capabilities, sanitization, slug uniqueness, revisions, rest_insert_*. The posts controller already does all of it, so calling it is less to get wrong than a second copy. No native implementation this time.

How?

File	What
Content_Write.php	the whole thing — registration, schemas, permission callbacks, and the POST /wp/v2/<rest_base>, POST /<id>, DELETE /<id> calls
Post_Type_Route.php	route and exposure helpers, extracted from Content_Rest.php
Rest_Backend.php	post() and delete() beside get()

One class, one implementation. There is no native/REST pair here — nothing reaches wp_insert_post() or its siblings directly.

Registered from Content::register(), where the placeholder comment said a write ability would go. The permission callbacks gate on the post type being exposed to abilities and on the caller's capability for the post; everything past that is the controller's.

An update sends only the fields the input names, so it leaves the rest alone. A delete trashes by default and reports { deleted, post }; force deletes permanently, and the post is read while it still exists. Written posts are reported by reading them back through Content_Rest, so one field mapping serves both directions.

Two helpers on Content became public (get_exposed_post_types(), get_post_properties()) so both sides gate on the same post types and report the same fields. Both are marked // Plugin:.

Testing

24 tests in Content_WriteTest.php. They assert the mapping this plugin owns and the controller behaviour it must pass on rather than swallow — the refusal to assign another author, an unparseable date, an already trashed post, and a post type that does not support trashing.

npm run wp-env:test start
npm run test:php      # 1611 tests
npm run test:php:rest # same totals

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Opus 5
Used for: The abilities, the REST mapping, the tests and this description were drafted with Claude Code and iterated against the suite in a local wp-env environment. I reviewed and edited the result, and I take responsibility for it.

Changelog Entry

Added - core/content-create, core/content-update and core/content-delete abilities for writing content, backed by the REST posts endpoint.

[github-actions]

✅ WordPress Plugin Check Report

✅ Status: Passed

📊 Report

All checks passed! No errors or warnings found.

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[codecov]

Codecov Report

❌ Patch coverage is 94.45910% with 21 lines in your changes missing coverage. Please review.
✅ Project coverage is 82.11%. Comparing base (27c393d) to head (13fc01f).

Files with missing lines	Patch %	Lines
includes/Abilities/Content/Content_Write.php	94.89%	17 Missing ⚠️
includes/Abilities/Content/Post_Type_Route.php	87.87%	4 Missing ⚠️

Additional details and impacted files

@@                            Coverage Diff                             @@
##             try/core-read-abilities-rest-backend    #1026      +/-   ##
==========================================================================
+ Coverage                                   81.12%   82.11%   +0.98%     
- Complexity                                   3069     3140      +71     
==========================================================================
  Files                                         126      128       +2     
  Lines                                       12007    12352     +345     
==========================================================================
+ Hits                                         9741    10143     +402     
+ Misses                                       2266     2209      -57     

Flag	Coverage Δ
unit	82.11% <94.45%> (+0.98%)	⬆️

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