console: piped lines run in order; cargo-valid: empty_world allows the first folder of the package path

The runner mounts the package at its host path, so / shows its first
folder: tmp locally, build in the Nix sandbox.

cli/tests/crates/cargo-valid/src/main.rs

@@ -99,11 +99,21 @@ mod tests {
             .unwrap()
             .map(|entry| entry.unwrap().file_name())
             .collect();
-        assert!(names.iter().all(|name| {
-            ["proc", "self", "run", "tmp"]
-                .iter()
-                .any(|allowed| name == allowed)
-        }));
+        // The runner mounts the package folder at its host path, so the first
+        // folder of that path also appears in `/` (for example `tmp` or `build`).
+        let package = env!("CARGO_MANIFEST_DIR")
+            .trim_start_matches('/')
+            .split('/')
+            .next()
+            .unwrap();
+        assert!(
+            names.iter().all(|name| {
+                ["proc", "self", "run", package]
+                    .iter()
+                    .any(|allowed| name == allowed)
+            }),
+            "{names:?}"
+        );
         for path in ["/proc", "/self", "/run"] {
             assert!(std::path::Path::new(path).is_dir());
         }