tests: add debugging output

The transient failures appear to be persisting and they are quite
difficult to debug. So include a full directory listing in the output of
every test failure.

1 files changed, 1 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 02e9724a..0fefcfab 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -75,6 +75,7 @@ features = ["suggestions"]
 [dev-dependencies]
 serde = "1.0.77"
 serde_derive = "1.0.77"
+walkdir = "2"
 
 [features]
 simd-accel = ["grep/simd-accel"]