Description of the Change

On the plugin settings page, replace the custom Mailchimp UI for admin notices to the standard WP admin notices API

Drawbacks

• Two systems for displaying messages. WP admin notices and the Mailchimp custom messages for the front end.

Possible regressions

While I've tested for all of these scenarios and fixed any issues I've found the following items are the most likely regressions.

• It's possible that some messages that should display as WP admin notices were missed and will still display as custom Mailchimp messages
  • It's possible that those messages that were not updated will not display at all due to removing custom message output on the plugin settings page
• It's possible that specialized message text will be stripped out by sanitization functions that have been introduced or tweaked

Closes #62

How to test the Change

WP Admin messages

A video recording can be made on request for any of the testing items below.

I've documented all of the possible testing scenarios that I found while making the changes, but due to the extensive list of areas to test I recommend making a note of any items that are too difficult or time consuming to efficiently test. We can then look at the items that were not tested and decide on a plan.

For example, testing the error message for an invalid Mailchimp API token would require finding a way to fail the OAuth flow while still navigating to the plugin settings page. It might be better to talk about items like that and brainstorm easier ways of ensuring regression proof code, such as relying on the OAuth test in /tests/cypress/e2e/connect.test.js or extending it.

Success message

Settings page URL: /wp-admin/admin.php?page=mailchimp_sf_options

• Save any option and the success message will display
  • (optional) If we really want to go above and beyond we could save every single option on the page to trigger all of the locations where the success message will display
  • Pro tip: Multiple admin notices will display at the same time. You can turn every option on and then every option off again. Caution should be taken for options that will conditionally hide or display other options.

Error message

• Set the users list to "-- Select a List --" and click "Update List"
• If a users lists can not be retrieved from Mailchimp then an error will display
• If a user does not have any lists in their Mailchimp account defined then an error will display

FE messages

FE messages should remain unchanged

Success Messages

Submit the form after filling out all required fields to trigger the success message

• Users that already exist as a contact will be subscribed without email verification required (I think)
• Users not already saved as a contact will receive a success message to verify their email

Error Messages

Submit the form without entering any details to trigger the error message
The following scenarios will also throw errors on the FE

• Required fields not filled out or invalid
• If Mailchimp API client won't work (invalid token, etc) then an error will be thrown
• If update existing is turned off in the plugin settings and the subscriber email already exists then an error will be thrown
• Error with API request adding subscriber to list (could trigger with chrome dev tools -> mobile device view -> go offline)

Changelog Entry

Changed - Plugin settings page success and error messages will now use WP admin notices
Changed - Renamed mailchimp_sf_global_msg function to mailchimp_sf_frontend_msg to differentiate functionality from WP admin notices that are used exclusively in the WP Admin

Credits

Props @MaxwellGarceau

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly. - Asked in pull request if this step is worth it
• I have added tests to cover my change.
• All new and existing tests pass.