register_block_style_handle( array $metadata, string $field_name )

Source

File: wp-includes/blocks.php

function register_block_style_handle( $metadata, $field_name ) {
	if ( empty( $metadata[ $field_name ] ) ) {
		return false;
	}
	$is_core_block = isset( $metadata['file'] ) && 0 === strpos( $metadata['file'], ABSPATH . WPINC );
	if ( $is_core_block && ! wp_should_load_separate_core_block_assets() ) {
		return false;
	}

	// Check whether styles should have a ".min" suffix or not.
	$suffix = SCRIPT_DEBUG ? '' : '.min';

	$style_handle = $metadata[ $field_name ];
	$style_path   = remove_block_asset_path_prefix( $metadata[ $field_name ] );

	if ( $style_handle === $style_path && ! $is_core_block ) {
		return $style_handle;
	}

	$style_uri = plugins_url( $style_path, $metadata['file'] );
	if ( $is_core_block ) {
		$style_path = "style$suffix.css";
		$style_uri  = includes_url( 'blocks/' . str_replace( 'core/', '', $metadata['name'] ) . "/style$suffix.css" );
	}

	$style_handle   = generate_block_asset_handle( $metadata['name'], $field_name );
	$block_dir      = dirname( $metadata['file'] );
	$style_file     = realpath( "$block_dir/$style_path" );
	$has_style_file = false !== $style_file;
	$version        = ! $is_core_block && isset( $metadata['version'] ) ? $metadata['version'] : false;
	$style_uri      = $has_style_file ? $style_uri : false;
	$result         = wp_register_style(
		$style_handle,
		$style_uri,
		array(),
		$version
	);
	if ( file_exists( str_replace( '.css', '-rtl.css', $style_file ) ) ) {
		wp_style_add_data( $style_handle, 'rtl', 'replace' );
	}
	if ( $has_style_file ) {
		wp_style_add_data( $style_handle, 'path', $style_file );
	}

	$rtl_file = str_replace( "$suffix.css", "-rtl$suffix.css", $style_file );
	if ( is_rtl() && file_exists( $rtl_file ) ) {
		wp_style_add_data( $style_handle, 'path', $rtl_file );
	}

	return $result ? $style_handle : false;
}