Query Loop block showing all posts when Sticky Posts set to "Only"

[RavanH]

When the Query Loop block has the option "Sticky Posts" set to "Only" and there are NO posts marked as Sticky, the block will show all the latest (non-sticky) posts.

This is related to the VERY old bug #28099 where an empty array passed to 'post__in' is ignored and the query variable is treated as not set.

The bug is set to WONTFIX because fixing it would break too many plugins. It now it affects the Query Loop block.

To reproduce:

1. Create a test page with the Query Loop block, set the parameter Sticky Posts to "Only".
2. Make sure there are NO posts marked as Sticky.

Expected result: no posts on the test page.

Found result: all latest non-sticky posts on the test page.

This filter will fix the issue:

add_filter( 'query_loop_block_query_vars', function( $query ) {
	if ( isset( $query['post__in'] ) && ! $query['post__in'] ) {
		$query['post__in'] = [0];
	}
	return $query;
} );

(since there is no Blocks component (yet?), I've filed this ticket against the Query component)

This fixes the issue where all non-sticky posts show up in the Query Loop block when Sticky Posts is set to "Only" and there are no sticky posts.

Additional (array) typecast for safety.

See https://core.trac.wordpress.org/ticket/57822

Trac ticket:

We ought to add a test for this for query block?

[ocean90]

I noticed that in ​Gutenberg this case is/was handled but it seems like it was never backported to core?

Commits ​https://github.com/WordPress/wordpress-develop/pull/4144/commits/526d9b1d853165f539f3bf05a684c063057d856b and ​https://github.com/WordPress/wordpress-develop/pull/4144/commits/2164f1f199ef8d5b56da0294a8accc5c353fd668 bring full parity with the changes in Gutenberg ​https://github.com/WordPress/gutenberg/blob/42dad571eac32c41a7ff34f0da80fcc4e5ceb3bd/lib/compat/wordpress-6.1/blocks.php#L171-L183 to synchronize Core and Gutenberg.

[hellofromTonya]

Good catch @ocean90!

Marking this ticket as a gutenberg-merge as ​PR 4144 synchronizes the changes from Gutenberg into Core.

Self-assigning for commit review.

Just for reference, the function ​will be under `6.2` compat folder , since we are including this change now.

So some links for GB in comments would be different.

[hellofromTonya]

Changing the component to Editor as this is bug is related to the Query Loop block, rather than to the Query component.

[hellofromTonya]

Testing Instructions

These steps define how to reproduce the issue, and indicate the expected behavior.

Steps to Reproduce

1. Add a new Post.
2. Add a Query Loop block.
3. Select "Start blank".
4. Select first layout.
5. Change "Sticky Posts" to "Only".
6. Publish the post.
7. View in the front-end. 🐞 Notice all of the non-sticky posts are showing.

Expected Results

When testing a patch to validate it works as expected:

• ✅ In the front-end, non-sticky posts should not show.

When reproducing a bug:

• ❌ In the front-end, the non-sticky posts are showing.

Test Report Icons:
🐞 <= Indicates where issue ("bug") occurs.
✅ <= Behavior is expected.
❌ <= Behavior is NOT expected.

[hellofromTonya]

Test Report: Able to reproduce the issue 🐞 (before applying PR 4144)

[hellofromTonya]

Test Report: applying PR 4144 resolves the issue ✅

[hellofromTonya]

Test Report

Patch tested: ​https://github.com/WordPress/wordpress-develop/pull/4144

Environment

• OS: macOS
• WordPress: trunk
• Localhost: wp-env (Docker)
• Plugins: none
• Theme: TT3
• Browser: Chrome

Actual Results

When reproducing a bug/defect:

• ❌ As trac57822-reproduce-bug-before-patch.gif​ shows, able to reproduce the issue in the front-end.

When testing the bugfix patch:

• ✅ As trac57822-after-patch.gif​ shows, the patch resolves the issue.

[hellofromTonya]

Patch: ​https://github.com/WordPress/wordpress-develop/pull/4144

• Confirmed the changes match ​the changes in Gutenberg ✅
• Test Report confirms this patch fixes the reported issue ✅

Ready for commit 👍 Prepping it now

[hellofromTonya]

In 55447:

Editor: Exclude non-sticky posts in Query Loop Block when set to "Only".

Fixes a front-end issue to not include non-sticky posts in the Query Loop block when it's "Sticky Post" is set to "Only", meaning only show sticky posts.

This change was made in Gutenberg between 5.8 to 6.0, but was not merged into Core.

Reference:

• ​Gutenberg code

Follow-up to [50945].

Props RavanH, sc0ttkclark, ocean90, sc0ttkclark, hellofromTonya, ntsekouras.
Fixes #57822.

Committed via https://core.trac.wordpress.org/changeset/55447.