vendor/tempfile/tests/tempfile.rs

   1 #![deny(rust_2018_idioms)]
   2
   3 use std::fs;
   4 use std::io::{Read, Seek, SeekFrom, Write};
   5 use std::sync::mpsc::{sync_channel, TryRecvError};
   6 use std::thread;
   7
   8 #[test]
   9 fn test_basic() {
  10     let mut tmpfile = tempfile::tempfile().unwrap();
  11     write!(tmpfile, "abcde").unwrap();
  12     tmpfile.seek(SeekFrom::Start(0)).unwrap();
  13     let mut buf = String::new();
  14     tmpfile.read_to_string(&mut buf).unwrap();
  15     assert_eq!("abcde", buf);
  16 }
  17
  18 #[test]
  19 fn test_cleanup() {
  20     let tmpdir = tempfile::tempdir().unwrap();
  21     {
  22         let mut tmpfile = tempfile::tempfile_in(&tmpdir).unwrap();
  23         write!(tmpfile, "abcde").unwrap();
  24     }
  25     let num_files = fs::read_dir(&tmpdir).unwrap().count();
  26     assert!(num_files == 0);
  27 }
  28
  29 // Only run this test on Linux. MacOS doesn't like us creating so many files, apparently.
  30 #[cfg(target_os = "linux")]
  31 #[test]
  32 fn test_pathological_cleaner() {
  33     let tmpdir = tempfile::tempdir().unwrap();
  34     let (tx, rx) = sync_channel(0);
  35     let cleaner_thread = thread::spawn(move || {
  36         let tmp_path = rx.recv().unwrap();
  37         while rx.try_recv() == Err(TryRecvError::Empty) {
  38             let files = fs::read_dir(&tmp_path).unwrap();
  39             for f in files {
  40                 // skip errors
  41                 if f.is_err() {
  42                     continue;
  43                 }
  44                 let f = f.unwrap();
  45                 let _ = fs::remove_file(f.path());
  46             }
  47         }
  48     });
  49
  50     // block until cleaner_thread makes progress
  51     tx.send(tmpdir.path().to_owned()).unwrap();
  52     // need 40-400 iterations to encounter race with cleaner on original system
  53     for _ in 0..10000 {
  54         let mut tmpfile = tempfile::tempfile_in(&tmpdir).unwrap();
  55         write!(tmpfile, "abcde").unwrap();
  56         tmpfile.seek(SeekFrom::Start(0)).unwrap();
  57         let mut buf = String::new();
  58         tmpfile.read_to_string(&mut buf).unwrap();
  59         assert_eq!("abcde", buf);
  60     }
  61
  62     // close the channel to make cleaner_thread exit
  63     drop(tx);
  64     cleaner_thread.join().expect("The cleaner thread failed");
  65 }