--- a/src/mem_env.rs	Fri Jul 08 13:23:03 2022 -0700
+++ b/src/mem_env.rs	Fri Jul 08 14:09:37 2022 -0700
@@ -181,7 +181,7 @@
         let mut children = Vec::new();
         for k in fs.keys() {
             if k.starts_with(&prefix) {
-                children.push(Path::new(k.trim_start_matches(&prefix)).to_owned());
+                children.push(Path::new(k.strip_prefix(&prefix).unwrap_or(&k)).to_owned());
             }
         }
         Ok(children)

--- a/src/version_set.rs	Fri Jul 08 13:23:03 2022 -0700
+++ b/src/version_set.rs	Fri Jul 08 14:09:37 2022 -0700
@@ -1124,8 +1124,8 @@
             ve.add_file(1, fmd);
             vs.log_and_apply(ve).unwrap();
 
-            assert!(opt.env.exists(Path::new("db/CURRENT")).unwrap());
-            assert!(opt.env.exists(Path::new("db/MANIFEST-000019")).unwrap());
+            assert!(opt.env.exists(&Path::new("db").join("CURRENT")).unwrap());
+            assert!(opt.env.exists(&Path::new("db").join("MANIFEST-000019")).unwrap());
             // next_file_num and last_seq are untouched by log_and_apply
             assert_eq!(21, vs.new_file_number());
             assert_eq!(22, vs.next_file_num);