1985. 1985/// unlike DefaultHasher (SipHash with randomly-seeded-but-toolchain-chosen
1986. 1986/// parameters). Session directories must remain reachable after toolchain
1987. 1987/// upgrades.
1988. 1988fn hash_cwd(cwd: &Path) -> String {
1989. 1989 let mut h: u64 = 0xcbf2_9ce4_8422_2325;
1990. 1990 for b in cwd.to_string_lossy().as_bytes() {
1991. 1991 h ^= u64::from(*b);
1992. 1992 h = h.wrapping_mul(0x0000_0100_0000_01b3);
1993. 1993 }
1994. 1994 format!("{h:016x}")
1995. 1995}
1996. 1996
1997. 1997#[cfg(all(test, unix))]
1998. 1998mod tests {
1999. 1999 #![allow(clippy::unwrap_used, clippy::expect_used)]
2000. 2000 use super::*;
2001. 2001
2002. 2002 /// A child being spawned holds a duplicate of every open descriptor
2003. 2003 /// until it execs; the duplicate here stands in for one.
2004. 2004 #[test]
2005. 2005 fn the_lock_lasts_exactly_as_long_as_the_handle() {
2006. 2006 let dir = tempfile::tempdir().unwrap();
2007. 2007 let path = dir.path().join("session.jsonl");
2008. 2008 std::fs::write(&path, "").unwrap();
2009. 2009
2010. 2010 let log = SessionLog::open(path.clone()).unwrap();
2011. 2011 assert!(matches!(
2012. 2012 SessionLog::open(path.clone()),
2013. 2013 Err(SessionError::Locked(_))
2014. 2014 ));
2015. 2015
2016. 2016 let duplicate = log.file.file.try_clone().unwrap();
2017. 2017 drop(log);
2018. 2018 SessionLog::open(path).expect("the dropped handle's lock stayed with a duplicate");
2019. 2019 drop(duplicate);
2020. 2020 }
2021. 2021}
2022. 2022