resolve_pattern_blocks( array $blocks ): array

1875function resolve_pattern_blocks( $blocks ) {1876	static $inner_content;1877	// Keep track of seen references to avoid infinite loops.1878	static $seen_refs = array();1879	$i                = 0;1880	while ( $i < count( $blocks ) ) {1881		if ( 'core/pattern' === $blocks[ $i ]['blockName'] ) {1882			$attrs = $blocks[ $i ]['attrs'];1883 1884			if ( empty( $attrs['slug'] ) ) {1885				++$i;1886				continue;1887			}1888 1889			$slug = $attrs['slug'];1890 1891			if ( isset( $seen_refs[ $slug ] ) ) {1892				// Skip recursive patterns.1893				array_splice( $blocks, $i, 1 );1894				continue;1895			}1896 1897			$registry = WP_Block_Patterns_Registry::get_instance();1898			$pattern  = $registry->get_registered( $slug );1899 1900			// Skip unknown patterns.1901			if ( ! $pattern ) {1902				++$i;1903				continue;1904			}1905 1906			$blocks_to_insert = parse_blocks( trim( $pattern['content'] ) );1907 1908			/*1909			 * For single-root patterns, add the pattern name to make this a pattern instance in the editor.1910			 * If the pattern has metadata, merge it with the existing metadata.1911			 */1912			if ( count( $blocks_to_insert ) === 1 ) {1913				$block_metadata                = $blocks_to_insert[0]['attrs']['metadata'] ?? array();1914				$block_metadata['patternName'] = $slug;1915 1916				/*1917				 * Merge pattern metadata with existing block metadata.1918				 * Pattern metadata takes precedence, but existing block metadata1919				 * is preserved as a fallback when the pattern doesn't define that field.1920				 * Only the defined fields (name, description, categories) are updated;1921				 * other metadata keys are preserved.1922				 */1923				foreach ( array(1924					'name'        => 'title', // 'title' is the field in the pattern object 'name' is the field in the block metadata.1925					'description' => 'description',1926					'categories'  => 'categories',1927				) as $key => $pattern_key ) {1928					$value = $pattern[ $pattern_key ] ?? $block_metadata[ $key ] ?? null;1929					if ( $value ) {1930						$block_metadata[ $key ] = is_array( $value )1931							? array_map( 'sanitize_text_field', $value )1932							: sanitize_text_field( $value );1933					}1934				}1935 1936				$blocks_to_insert[0]['attrs']['metadata'] = $block_metadata;1937			}1938 1939			$seen_refs[ $slug ] = true;1940			$prev_inner_content = $inner_content;1941			$inner_content      = null;1942			$blocks_to_insert   = resolve_pattern_blocks( $blocks_to_insert );1943			$inner_content      = $prev_inner_content;1944			unset( $seen_refs[ $slug ] );1945			array_splice( $blocks, $i, 1, $blocks_to_insert );1946 1947			// If we have inner content, we need to insert nulls in the1948			// inner content array, otherwise serialize_blocks will skip1949			// blocks.1950			if ( $inner_content ) {1951				$null_indices  = array_keys( $inner_content, null, true );1952				$content_index = $null_indices[ $i ];1953				$nulls         = array_fill( 0, count( $blocks_to_insert ), null );1954				array_splice( $inner_content, $content_index, 1, $nulls );