fn clean_files(pattern: &str) -> Result<(), Box<dyn Error>> {

    let files: Result<Vec<PathBuf>, _> = glob(pattern)?.collect();

    files?.iter().try_for_each(remove_file)

}

fn remove_file<P>(path: P) -> Result<(), Box<dyn Error>>

where

    P: AsRef<Path>,

{

    fsx::file::remove(path)?;

    Ok(())

}

fn remove_dir<P>(path: P) -> Result<(), Box<dyn Error>>

where

    P: AsRef<Path>,

{

    fsx::dir::remove(path)?;

    Ok(())

}

pub fn coverage(cargo_arguments: Vec<String>) -> Result<(), Box<dyn Error>> {

    remove_dir("target/coverage")?;

    create_dir_all("target/coverage")?;

    println!("=== running coverage ===");

    // The path from which cargo is called.

    let mut base_directory = env::current_dir().unwrap();

    base_directory.push("target");

    base_directory.push("coverage");

    let mut prof_directory = base_directory.clone();

    prof_directory.push("cargo-test-%p-%m.profraw");

    cmd("cargo", cargo_arguments)

        .env("CARGO_INCREMENTAL", "0")

        .env("RUSTFLAGS", "-Cinstrument-coverage")

        .env("LLVM_PROFILE_FILE", prof_directory)

        .run()?;

    println!("ok.");

    println!("=== generating report ===");

    let (fmt, file) = ("html", "target/coverage/html");

    cmd!(

        "grcov",

        base_directory,

        "--binary-path",

        "./target/debug/deps",

        "-s",

        ".",

        "-t",

        fmt,

        "--branch",

        "--ignore-not-existing",

        "--ignore",

        "**/target/*",

        "-o",

        file,

    )

    .run()?;

    println!("ok.");

    println!("=== cleaning up ===");

    clean_files("**/*.profraw")?;

    println!("ok.");

    println!("report location: {file}");

    Ok(())

}