//! A temporary directory for a test, removed with everything in it when the value is dropped
//! (tip T44). Included with `#[path = "support/temp.rs"] mod temp;`.

#![allow(dead_code)] // each test file uses a different part of this module

use std::ffi::OsStr;
use std::ops::Deref;
use std::path::{Path, PathBuf};
use std::sync::atomic::{AtomicU32, Ordering};

static NEXT: AtomicU32 = AtomicU32::new(0);

pub struct TempDir(PathBuf);

impl TempDir {
    /// A fresh, empty directory `<temp>/<tag>-<pid>-<n>`.
    pub fn new(tag: &str) -> TempDir {
        let n = NEXT.fetch_add(1, Ordering::SeqCst);
        let path = std::env::temp_dir().join(format!("{tag}-{}-{n}", std::process::id()));
        let _ = std::fs::remove_dir_all(&path);
        std::fs::create_dir_all(&path).unwrap();
        TempDir(path)
    }
}

impl Deref for TempDir {
    type Target = Path;
    fn deref(&self) -> &Path {
        &self.0
    }
}

impl AsRef<Path> for TempDir {
    fn as_ref(&self) -> &Path {
        &self.0
    }
}

impl AsRef<OsStr> for TempDir {
    fn as_ref(&self) -> &OsStr {
        self.0.as_os_str()
    }
}

impl Drop for TempDir {
    fn drop(&mut self) {
        // Put back the permissions a test may have taken away, or the removal fails.
        use std::os::unix::fs::PermissionsExt;
        let _ = std::fs::set_permissions(&self.0, std::fs::Permissions::from_mode(0o700));
        let _ = std::fs::remove_dir_all(&self.0);
    }
}