Add cache invalidation for header images

Introduce `invalidate_header_images_cache` function to clear cached header images when custom header meta is updated or deleted. Add corresponding unit tests to ensure cache invalidation logic works correctly.

src/wp-includes/theme.php

@@ -1547,11 +1547,33 @@ function get_uploaded_header_images() {
 		}
 	}
 
-	set_transient( $transient_key, $header_images, HOUR_IN_SECONDS );
+	set_transient( $transient_key, $header_images, DAY_IN_SECONDS );
 
 	return $header_images;
 }
 
+/**
+ * Invalidates the cache for header images when a custom header image is changed or deleted.
+ *
+ * @since 6.7
+ *
+ * @param int $meta_id The meta ID of the attachment meta data.
+ * @param int $post_id The post ID of the attachment.
+ * @param string $meta_key The meta key of the attachment meta data.
+ * @param mixed $meta_value The new value of the attachment meta data.
+ *
+ * @return void
+ */
+function invalidate_header_images_cache( $meta_id, $post_id, $meta_key, $meta_value ) {
+	if ( '_wp_attachment_is_custom_header' === $meta_key ) {
+		$stylesheet    = get_option( 'stylesheet' );
+		$transient_key = 'uploaded_header_images' . $stylesheet;
+		delete_transient( $transient_key );
+	}
+}
+add_action( 'updated_post_meta', 'invalidate_header_images_cache', 10, 4 );
+add_action( 'deleted_post_meta', 'invalidate_header_images_cache', 10, 4 );
+
 /**
  * Gets the header image data.
  *

tests/phpunit/tests/theme/getUploadedHeaderImages.php

@@ -1,6 +1,8 @@
 <?php
 /**
  * @group themes
+ *
+ * @coversDefaultClass ::get_uploaded_header_images
  */
 class Tests_Theme_GetUploadedHeaderImages extends WP_UnitTestCase {
 	public $custom_image_header;

tests/phpunit/tests/theme/invalidateHeaderImagesCache.php

@@ -0,0 +1,112 @@
+<?php
+/**
+ * @group themes
+ *
+ * @coversDefaultClass ::invalidate_header_images_cache
+ */
+class Tests_Theme_invalidateHeaderImagesCache extends WP_UnitTestCase {
+	public $custom_image_header;
+
+	public function set_up() {
+		parent::set_up();
+		$this->custom_image_header = new Custom_Image_Header( '__return_null' );
+	}
+
+	/**
+	 * @ticket 49446
+	 */
+	public function test_invalidate_header_images_cache_meta_updated() {
+		$id = wp_insert_attachment(
+			array(
+				'post_status' => 'publish',
+				'post_title'  => 'foo.png',
+				'post_type'   => 'post',
+				'guid'        => 'http://localhost/foo.png',
+			)
+		);
+
+		// Create initial crop object.
+		$cropped_1 = 'foo-cropped-1.png';
+		$object    = wp_copy_parent_attachment_properties( $cropped_1, $id, 'custom-header' );
+
+		// Ensure no previous crop exists.
+		$previous = $this->custom_image_header->get_previous_crop( $object );
+		$this->assertFalse( $previous );
+
+		// Create the initial crop attachment and set it as the header.
+		$cropped_1_id = $this->custom_image_header->insert_attachment( $object, $cropped_1 );
+		$key          = '_wp_attachment_custom_header_last_used_' . get_stylesheet();
+		update_post_meta( $cropped_1_id, $key, time() );
+		update_post_meta( $cropped_1_id, '_wp_attachment_is_custom_header', get_stylesheet() );
+
+		$expected = array(
+			$cropped_1_id => array(
+				'attachment_id'     => $cropped_1_id,
+				'url'               => 'http://example.org/wp-content/uploads/foo-cropped-1.png',
+				'thumbnail_url'     => 'http://example.org/wp-content/uploads/foo-cropped-1.png',
+				'alt_text'          => '',
+				'attachment_parent' => $id,
+			),
+		);
+
+		$num_queries = get_num_queries() + 4;
+
+		$this->assertSame( $expected, get_uploaded_header_images() );
+
+		$this->assertSame( $num_queries, get_num_queries() );
+		update_post_meta( $cropped_1_id, '_wp_attachment_is_custom_header', 'updated' );
+
+		$stylesheet    = get_option( 'stylesheet' );
+		$transient_key = 'uploaded_header_images' . $stylesheet;
+		$this->assertFalse( get_transient( $transient_key ), 'cache cleared' );
+	}
+
+	/**
+	 * @ticket 49446
+	 */
+	public function test_invalidate_header_images_cache_meta_deleted() {
+		$id = wp_insert_attachment(
+			array(
+				'post_status' => 'publish',
+				'post_title'  => 'foo.png',
+				'post_type'   => 'post',
+				'guid'        => 'http://localhost/foo.png',
+			)
+		);
+
+		// Create initial crop object.
+		$cropped_1 = 'foo-cropped-1.png';
+		$object    = wp_copy_parent_attachment_properties( $cropped_1, $id, 'custom-header' );
+
+		// Ensure no previous crop exists.
+		$previous = $this->custom_image_header->get_previous_crop( $object );
+		$this->assertFalse( $previous );
+
+		// Create the initial crop attachment and set it as the header.
+		$cropped_1_id = $this->custom_image_header->insert_attachment( $object, $cropped_1 );
+		$key          = '_wp_attachment_custom_header_last_used_' . get_stylesheet();
+		update_post_meta( $cropped_1_id, $key, time() );
+		update_post_meta( $cropped_1_id, '_wp_attachment_is_custom_header', get_stylesheet() );
+
+		$expected = array(
+			$cropped_1_id => array(
+				'attachment_id'     => $cropped_1_id,
+				'url'               => 'http://example.org/wp-content/uploads/foo-cropped-1.png',
+				'thumbnail_url'     => 'http://example.org/wp-content/uploads/foo-cropped-1.png',
+				'alt_text'          => '',
+				'attachment_parent' => $id,
+			),
+		);
+
+		$num_queries = get_num_queries() + 4;
+
+		$this->assertSame( $expected, get_uploaded_header_images() );
+
+		$this->assertSame( $num_queries, get_num_queries() );
+		delete_post_meta( $cropped_1_id, '_wp_attachment_is_custom_header' );
+
+		$stylesheet    = get_option( 'stylesheet' );
+		$transient_key = 'uploaded_header_images' . $stylesheet;
+		$this->assertFalse( get_transient( $transient_key ), 'cache cleared' );
+	}
+}