Intermittent failures running cargo test

[joekain]

I was trying to track down some intermittent failures with some new tests I was writing and write a script to run cargo test over and over. With master I see 3 distinct failures signatures:

1. This is due to an off-by-one error in sys::test_uio::test_readv. I have a change to fix this and will submit a PR.
   failures:

   ---- sys::test_uio::test_readv stdout ----
   thread 'sys::test_uio::test_readv' panicked at 'Rng.gen_range called with low >= high', /home/joseph/.cargo/registry/src/github.com-0a35038f75765ae4/rand-0.3.8/src/lib.rs:441
   
   
   
   failures:
   sys::test_uio::test_readv
   

2. I think this is due to tests running tests in parallel and wait() waking up for a different child than expected. Is there a way to run tests in isolation?
   failures:

   ---- test_unistd::test_wait stdout ----
       thread 'test_unistd::test_wait' panicked at 'assertion failed: `(left == right)` (left: `Ok(Exited(21710))`, right: `Ok(Exited(21714))`)', test/test_unistd.rs:41
   
   
   ---- test_unistd::test_execve stdout ----
       thread 'test_unistd::test_execve' panicked at 'called `Result::unwrap()` on an `Err` value: Sys(ECHILD)', ../src/libcore/result.rs:731
   
   
   
   failures:
       test_unistd::test_execve
       test_unistd::test_wait
   

3. This one takes longer to reproduce. I'm not sure what the problem is here.
   failures:

   ---- sys::test_termios::test_tcgetattr stdout ----
       thread 'sys::test_termios::test_tcgetattr' panicked at 'assertion failed: `(left == right)` (left: `Some(Sys(ENOTTY))`, right: `Some(Sys(EBADF))`)', test/sys/test_termios.rs:15
   
   
   
   failures:
       sys::test_termios::test_tcgetattr
   

Please let me know if I should file 3 separate issues for these.

[carllerche]

Merged this. Thanks!

[joekain]

Oops, I guess I should have filed 3 separate issues. Problems 2 and 3 still persist. I'll file new issues for them.