fix(reader-data): make is_donor read-only only when platform has server-side tracking

[jason10lee]

Changes proposed:

The is_donor reader data key was made unconditionally read-only in #4532, which broke a Campaigns feature that sets is_donor client-side on post-transaction landing pages. This mainly affects sites using non-Newspack donation platforms (NRH, other) where there is no server-side path to set the flag.

This PR makes is_donor conditionally read-only based on whether the donation platform has server-side donor tracking:

• WooCommerce sites: is_donor remains read-only. The donation_new data event handles it server-side.
• NRH / other sites: is_donor is writable, allowing the existing client-side landing page flow to work for both anonymous and logged-in readers.

The change introduces Donations::has_server_side_donor_tracking(), a capability method that decouples the policy ("does this platform manage donor status server-side?") from the platform identifier. Future platforms with secure server-side handling add themselves to this one method.

Note: when is_donor is not read-only, any authenticated reader can set it via the REST API. This is an intentional trade-off documented in the code — is_donor is used for segmentation and analytics, not access control. Consumers that need to distinguish server-verified from client-asserted donor status should check Donations::has_server_side_donor_tracking().

Fixes NPPD-1431: Allow non-Woo integrations to write is_donor.

How to test:

1. With the donation platform set to WooCommerce (default):

   • Confirm is_donor is in the read-only keys list: in the browser console, check newspack_reader_data.read_only_keys includes is_donor.
   • As a logged-in reader, confirm that window.newspackReaderActivation.store.set('is_donor', true) throws a read-only error.

2. Switch the donation platform to NRH (Audience > Checkout & Payment):

   • Confirm is_donor is NOT in newspack_reader_data.read_only_keys.
   • As a logged-in reader, confirm that window.newspackReaderActivation.store.set('is_donor', true) succeeds without error.
   • Confirm the value persists in localStorage as np_reader_1_is_donor.

   Note: If switching via WP-CLI (wp option update newspack_reader_revenue_platform nrh), run wp cache flush afterward to clear the autoloaded option cache. Switching via the admin UI flushes the cache automatically. This bit yr. humble dev while he was trying to red/green test, so making a note of it!

[Copilot]

Pull request overview

Adjusts Reader Data’s is_donor read-only enforcement to depend on whether the active donations platform supports server-side donor tracking, restoring the client-side donor-landing-page flow for non-Woo platforms.

Changes:

• Makes Reader_Data::get_read_only_keys() include is_donor only when Donations::has_server_side_donor_tracking() is true.
• Introduces Donations::has_server_side_donor_tracking() capability method (currently true for WooCommerce only).
• Adds unit tests covering platform-conditional behavior and the read-only-keys filter.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
tests/unit-tests/reader-data-read-only-keys.php	Adds unit tests for platform-conditional is_donor read-only behavior and filter behavior.
includes/reader-activation/class-reader-data.php	Builds read-only key list dynamically; conditionally includes is_donor based on server-side tracking capability.
includes/class-donations.php	Adds has_server_side_donor_tracking() to centralize the “server-side donor tracking” capability check.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.