Theme starter content pages 404 if multiple auto-drafts were saved

[dlh]

Steps to replicate running Twenty Seventeen on a "fresh" install:

• Open the Customizer
• Do something that adds new auto-drafts of the starter content. For example, refresh the Customizer.
• Publish the starter content.
• Visit the frontend and attempt to navigate to one of the starter content page, like "Contact," and see the page 404.

Publishing the starter content publishes the most-recently created auto-draft, but the earlier ones (with lower IDs) remain. get_page_by_path() doesn't account for post status, so when you visit the starter content page, the query returns the auto-draft.

[westonruter]

@dlh another great catch. As we were talking at contributor day, our first thought was to make get_page_by_path() exclude auto-draft posts. But this could have the negative effect of making the posts/pages inaccessible in the preview. Also, there could be some plugins that are expecting get_page_by_path() to include auto-drafts, and so it is dangerous to change that at this point during RC2.

So what we discussed together with @mboynes was to leave the post_name empty when importing starter content, but to then instead store the post_name in postmeta for that post. Then when the post is published, at that time we can supply that post_name at the time of publishing.

[westonruter]

This is directly related to [39412] for #38928.

[dlh]

@westonruter The patch fixes the issue in my testing.

I noticed one side effect: If the Customizer loads with starter content, and there is a url query parameter for a starter content page (like ?url=http%3A%2F%2Fwp.dev%2Fcontact%2F), the preview will show "not found." It looks like the Customizer attempts to preview /contact/, which invokes get_page_by_path(), which in turn queries for a post_name.

But I got into this scenario as I was reinstalling and refreshing quite a bit during testing, and I'm not sure how it would naturally occur. Plus, if you then click the link to the page in the nav menu, the starter content works as expected.

[westonruter]

@dlh thanks so much for testing. Yes, the scenario you described is to be expected and is not a defect. Since the post_name is empty then only the non-pretty permalinks would ever be used for such starter content.

[westonruter]

s/_starter_content_post_name/_customize_draft_post_name/g

[westonruter]

Revert wp_unique_post_slug() changes from [39411]/bdd33e9dff: ​https://github.com/xwp/wordpress-develop/pull/211/commits/8ab4a78ef51182e600b2abdfae074d998929e04a

[westonruter]

Fix ajax unit tests: ​https://github.com/xwp/wordpress-develop/pull/211/commits/84b9898

[dlh]

I'm not sure whether it was intentional, but starter content attachments still receive a post_name. When the starter content is published, the slug ends up, e.g., /espresso-2/.

Either way, 39078.4.diff​ still fixes the original issue for me.

[westonruter]

Ensure that attachments also have their post_name set only when publishing: ​https://github.com/xwp/wordpress-develop/pull/211/commits/c193206575bffc5644f721b07c07b970c3f0c22b

[westonruter]

@dlh you're absolutely right. Great catch. Fixed in 39078.5.diff​.

[helen]

Looking good here.

[dlh]

Pages and attachments look good to me in 39078.5.diff​.

[westonruter]

In 39506:

Customize: Defer populating post_name for auto-draft posts in customized state until posts are published.

The ultimate post_name is stored in postmeta until the post is published. The get_page_by_path() function does not exclude auto-draft posts. Revert changes to wp_unique_post_slug() from [39411] which excluded auto-draft posts.

Props westonruter, dlh for testing, helen for testing.
See #38114, #38928.
Fixes #39078.

[westonruter]

In 39507:

Customize: Defer populating post_name for auto-draft posts in customized state until posts are published.

The ultimate post_name is stored in postmeta until the post is published. The get_page_by_path() function does not exclude auto-draft posts. Revert changes to wp_unique_post_slug() from [39411] which excluded auto-draft posts.

Props westonruter, dlh for testing, helen for testing.
Merges [39506] onto 4.7 branch.
Fixes #39078 for 4.7.