You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: directive_list.rs
    path of file: ./repos/biome/crates/biome_js_formatter/src/js/lists
    
    the code of the file until where you have to start completion: use crate::prelude::*;
use biome_formatter::write;
use biome_js_syntax::JsDirectiveList;
use biome_rowan::{AstNode, AstNodeList};

#[derive(Debug, Clone, Default)]
pub(crate) struct FormatJsDirectiveList;

impl FormatRule<JsDirectiveList> for FormatJsDirectiveList {
    type Context = JsFormatContext;

    fn fmt(&self, node: &JsDirectiveList, f: &mut JsFormatter) -> FormatResult<()> {
        if node.is_empty() {
            return Ok(());
        }

        let syntax_node = node.syntax();
        let next_sibling = syntax_node.next_sibling();
        // if next_sibling's first leading_trivia has more than one new_line, we should add an extra empty line at the end of
        // JsDirectiveList, for example:
        //```js
        // "use strict"; <- first leading new_line
        //  			 <- second leading new_line
        // function foo() {

        // }
        //```
        // so we should keep an extra empty line after JsDirectiveList
        let need_extra_empty_lin
    
    fn fmt(&self, node: &JsDirectiveList, f: &mut JsFormatter) -> FormatResult<()> {
        if node.is_empty() {
            return Ok(());
        }

        let syntax_node = node.syntax();
        let next_sibling = syntax_node.next_sibling();
        // if next_sibling's first leading_trivia has more than one new_line, we should add an extra empty line at the end of
        // JsDirectiveList, for example:
        //```js
        // "use strict"; <- first leading new_line
        //  			 <- second leading new_line
        // function foo() {

        // }
        //```
        // so we should keep an extra empty line after JsDirectiveList
        let need_extra_empty_line = if let Some(next_sibling) = next_sibling {
            get_lines_before(&next_sibling) > 1
        } else {
            false
        };

        let mut join = f.join_nodes_with_hardline();

        for directive in node {
            join.entry(directive.syntax(), &directive.format());
        }

        join.finish()?;

        if need_extra_empty_line {
            write!(f, [empty_line()])
        } else {
            write!(f, [hard_line_break()])
        }
    }