fix(tvix): make rstest pick up new test case files

Context: https://github.com/la10736/rstest/issues/256

Cargo will now cause a rebuild whenever a new test case file is added.
Previsouly running `cargo test` after adding a new test case resulted in
that case not being picked up and ignored.

Change-Id: Ibfc420b5bfe3f3ee41d3ebd3fb9d248819fa6ed9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/11751
Reviewed-by: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Autosubmit: Ilan Joselevich <personal@ilanjoselevich.com>

tvix/eval/build.rs

@@ -5,5 +5,10 @@ fn main() {
         "cargo:rustc-env=TVIX_CURRENT_SYSTEM={}",
         &env::var("TARGET").unwrap()
     );
-    println!("cargo:rerun-if-changed-env=TARGET")
+    println!("cargo:rerun-if-changed-env=TARGET");
+
+    // Pick up new test case files
+    // https://github.com/la10736/rstest/issues/256
+    println!("cargo:rerun-if-changed=src/tests/nix_tests");
+    println!("cargo:rerun-if-changed=src/tests/tvix_tests")
 }

tvix/glue/build.rs

@@ -0,0 +1,6 @@
+fn main() {
+    // Pick up new test case files
+    // https://github.com/la10736/rstest/issues/256
+    println!("cargo:rerun-if-changed=src/tests/nix_tests");
+    println!("cargo:rerun-if-changed=src/tests/tvix_tests")
+}

tvix/nix-compat/build.rs

@@ -0,0 +1,5 @@
+fn main() {
+    // Pick up new test case files
+    // https://github.com/la10736/rstest/issues/256
+    println!("cargo:rerun-if-changed=src/derivation/tests/derivation_tests")
+}