rust: fix testing with $TMPDIR ≠ /tmp

Differential Revision: https://phab.mercurial-scm.org/D9670

rust/hg-core/src/utils/path_auditor.rs

@@ -206,6 +206,7 b' mod tests {'
 
         let base_dir = tempdir().unwrap();
         let base_dir_path = base_dir.path();
+        let skip = base_dir_path.components().count() - 1;
         let a = base_dir_path.join("a");
         let b = base_dir_path.join("b");
         create_dir(&a).unwrap();
@@ -215,7 +216,7 b' mod tests {'
         // TODO make portable
         std::os::unix::fs::symlink(&a, &b).unwrap();
 
-        let buf = b.join("in_a").components().skip(2).collect::<PathBuf>();
+        let buf = b.join("in_a").components().skip(skip).collect::<PathBuf>();
         eprintln!("buf: {}", buf.display());
         let path = path_to_hg_path_buf(buf).unwrap();
         assert_eq!(