//! Temporary directories for tests. Do not edit.
//!
//! Included with `#[path = "support/tmp.rs"] mod tmp;`. No crate is used: the name is made from
//! the process id and a counter, and the directory is removed when the value is dropped.

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

use std::path::{Path, PathBuf};
use std::sync::atomic::{AtomicU32, Ordering};

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

pub struct TempDir(PathBuf);

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

    pub fn path(&self) -> &Path {
        &self.0
    }

    /// Writes `text` to `name` inside the directory and returns the full path.
    pub fn write(&self, name: &str, text: &str) -> PathBuf {
        let path = self.0.join(name);
        std::fs::write(&path, text).unwrap();
        path
    }
}

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);
    }
}

/// True when the tests run as root, for whom file permissions do not apply. Tests that depend on
/// a permission error print why they are skipped and return.
pub fn running_as_root(test: &str) -> bool {
    let probe = TempDir::new("rootprobe");
    let file = probe.write("probe", "x");
    use std::os::unix::fs::PermissionsExt;
    std::fs::set_permissions(&file, std::fs::Permissions::from_mode(0o000)).unwrap();
    let root = std::fs::read(&file).is_ok();
    if root {
        eprintln!("{test}: skipped, because this user can read a mode 000 file (root?)");
    }
    root
}