From d57ecb8b980c5a6ad2b68369750e592f6db4bd09 Mon Sep 17 00:00:00 2001
From: Peter Wilson <wilson@peterwilson.cc>
Date: Mon, 3 Mar 2025 21:45:21 +0000
Subject: [PATCH] Query: Ensure secondary loops populate the full global post.

Modifies `WP_Query::the_post()` to ensure the entire global post object is populated regardless of the `fields` parameter initially set by the developer.

In secondary loops, this ensures that `get_the_content()` and other getter functions operate as documented when called without a post ID and return the appropriate data for the global post object.

This introduces consistency when starting the loop and the `fields` parameter is set to `id=>parent` to the behaviour when set to either `all` or `ids`.

There is no change to the `WP_Query::$posts` parameter nor when a query is made without starting the secondary loop, ie without calling `WP_Query::the_post()`.

Props juzar, mukesh27, oglekler, peterwilsoncc, sirlouen, joemcgill.
Fixes #56992.


Built from https://develop.svn.wordpress.org/trunk@59919


git-svn-id: http://core.svn.wordpress.org/trunk@59261 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/class-wp-query.php | 34 +++++++++++++++++++++++++++++-----
 wp-includes/version.php        |  2 +-
 2 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/wp-includes/class-wp-query.php b/wp-includes/class-wp-query.php
index e7ad0a0f72..a62d05e3e2 100644
--- a/wp-includes/class-wp-query.php
+++ b/wp-includes/class-wp-query.php
@@ -3738,14 +3738,28 @@ class WP_Query {
 		global $post;
 
 		if ( ! $this->in_the_loop ) {
-			// Only prime the post cache for queries limited to the ID field.
-			$post_ids = array_filter( $this->posts, 'is_numeric' );
-			// Exclude any falsey values, such as 0.
-			$post_ids = array_filter( $post_ids );
+			// Get post IDs to prime incomplete post objects.
+			$post_ids = array_reduce(
+				$this->posts,
+				function ( $carry, $post ) {
+					if ( is_numeric( $post ) && $post > 0 ) {
+						// Query for post ID.
+						$carry[] = $post;
+					}
+
+					if ( is_object( $post ) && isset( $post->ID ) ) {
+						// Query for object, either WP_Post or stdClass.
+						$carry[] = $post->ID;
+					}
+
+					return $carry;
+				},
+				array()
+			);
 			if ( $post_ids ) {
 				_prime_post_caches( $post_ids, $this->query_vars['update_post_term_cache'], $this->query_vars['update_post_meta_cache'] );
 			}
-			$post_objects = array_map( 'get_post', $this->posts );
+			$post_objects = array_map( 'get_post', $post_ids );
 			update_post_author_caches( $post_objects );
 		}
 
@@ -3764,6 +3778,16 @@ class WP_Query {
 		}
 
 		$post = $this->next_post();
+
+		// Get the post ID.
+		if ( is_object( $post ) ) {
+			$global_post_id = $post->ID;
+		} else {
+			$global_post_id = $post;
+		}
+
+		// Ensure the global $post is the full post object.
+		$post = get_post( $global_post_id );
 		$this->setup_postdata( $post );
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index dbf6972d33..ca34392fbd 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.8-alpha-59918';
+$wp_version = '6.8-alpha-59919';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.