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: test_case.rs
    path of file: ./repos/tools/xtask/bench/src
    
    the code of the file until where you have to start completion: use crate::err_to_string;
use ansi_rgb::{red, Foreground};
use std::env;
use std::path::{Path, PathBuf};
use std::str::FromStr;

pub struct TestCase {
    code: String,
    id: String,
    path: PathBuf,
}

impl TestCase {
    pub fn try_from(test_case: &str) -> Result<TestCase, String> {
        let url = url::Url::from_str(test_case).map_err(err_to_string)?;
        let segments = url
            .path_segments()
            .ok_or_else(|| "lib url has no segments".to_string())?;
        let filename = segments
            .last()
            .ok_or_else(|| "lib url has no segments".to_string())?;

        let path = Path::new(
            &env::var("CARGO_MANIFEST_DIR")
                .unwrap_or_else(|_| env!("CARGO_MANIFEST_DIR").to_owned()),
        )
        .ancestors()
        .nth(2)
        .unwrap()
        .join("target")
        .join(filename);

        let content = std::fs::read_to_string(&path)
            .map_err(err_to_string)
            .or_else(|_| {
                println!(
                    "[{}] - Downloading [{}] to [{}]",
                    filename,
                    test_case,
                    path.display()
                );
                match ureq::get(test_case).call() {
                    Ok(response) => {
                        let mut reader = response.into_reader();

                        let mut writer = std::fs::File::create(&path).map_err(err_to_string)?;
                        if let Err(err) = std::io::copy(&mut reader, &mut writer) {
                            drop(writer);
                            std::fs::remove_file(&path).ok();
                            return Err(err_to_string(err));
                        }
                        std::fs::read_to_string(&path).map_err(err_to_string)
                  
    
    pub fn try_from(test_case: &str) -> Result<TestCase, String> {
        let url = url::Url::from_str(test_case).map_err(err_to_string)?;
        let segments = url
            .path_segments()
            .ok_or_else(|| "lib url has no segments".to_string())?;
        let filename = segments
            .last()
            .ok_or_else(|| "lib url has no segments".to_string())?;

        let path = Path::new(
            &env::var("CARGO_MANIFEST_DIR")
                .unwrap_or_else(|_| env!("CARGO_MANIFEST_DIR").to_owned()),
        )
        .ancestors()
        .nth(2)
        .unwrap()
        .join("target")
        .join(filename);

        let content = std::fs::read_to_string(&path)
            .map_err(err_to_string)
            .or_else(|_| {
                println!(
                    "[{}] - Downloading [{}] to [{}]",
                    filename,
                    test_case,
                    path.display()
                );
                match ureq::get(test_case).call() {
                    Ok(response) => {
                        let mut reader = response.into_reader();

                        let mut writer = std::fs::File::create(&path).map_err(err_to_string)?;
                        if let Err(err) = std::io::copy(&mut reader, &mut writer) {
                            drop(writer);
                            std::fs::remove_file(&path).ok();
                            return Err(err_to_string(err));
                        }
                        std::fs::read_to_string(&path).map_err(err_to_string)
                    }
                    Err(e) => Err(err_to_string(e)),
                }
            });

        content.map(|code| {
            println!("[{}] - using [{}]", filename.fg(red()), path.display());
            TestCase {
                id: filename.to_string(),
                code,
                path,
            }
        })
    }