feat(tvix/castore): add rstest-based DirectoryService tests r/7777

This creates test scenarios (using the DirectoryService trait) that we
want all DirectoryService implementations to pass.

Some of these tests are ported from proto::tests::grpc_directoryservice,
which tested this on the gRPC interface (rather than the trait),
some others ensure certain behaviour for which we only recently
introduced general checking logic (through ClosureValidator).

We also borrow some code related to setting up a gRPC DirectoryService
client (connecting to a server exposing a in-memory DiretoryService)
from castore::utils, this will be deleted once it's all ported over.

Change-Id: I6810215a76101f908e2aaecafa803c70d85bc552
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11247
Reviewed-by: raitobezarius <tvl@lahfa.xyz>
Autosubmit: flokli <flokli@flokli.de>
Reviewed-by: Connor Brewster <cbrewster@hey.com>
Tested-by: BuildkiteCI

1 files changed, 6 insertions, 0 deletions

diff --git a/tvix/castore/src/lib.rs b/tvix/castore/src/lib.rs
index dec7684b4c57..1ce092135b83 100644
--- a/tvix/castore/src/lib.rs
+++ b/tvix/castore/src/lib.rs
@@ -20,3 +20,9 @@ pub use hashing_reader::{B3HashingReader, HashingReader};
 
 #[cfg(test)]
 mod tests;
+
+// That's what the rstest_reuse README asks us do, and fails about being unable
+// to find rstest_reuse in crate root.
+#[cfg(test)]
+#[allow(clippy::single_component_path_imports)]
+use rstest_reuse;