From 54508d8ec26d6f988e8a3b0ab22c4fe775c46645 Mon Sep 17 00:00:00 2001
From: Matthew Jackson <1085847+MattJackson@users.noreply.github.com>
Date: Mon, 28 Sep 2026 06:28:47 -0700
Subject: [PATCH] KU-E1 review minor 4 red: partial stored keys plus a Km still
 report NoVid

A keydb entry with stored unit keys for some CPS units and a Media Key
but no VID returns the stored keys with an empty miss path, so
resolve cannot tell that the VID would derive the rest (J23).
---
 src/keydb.rs | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/keydb.rs b/src/keydb.rs
index a8f88e6..ff37c03 100644
--- a/src/keydb.rs
+++ b/src/keydb.rs
@@ -792,6 +792,19 @@ mod tests {
         assert!(!shape.vid_available);
     }
 
+    // KU J23: stored unit keys for SOME CPS units plus a Media Key with no VID. The stored
+    // keys come back, and the miss path still says `NoVid`: the VID would derive the rest.
+    #[test]
+    fn partial_stored_keys_with_a_media_key_and_no_vid_report_no_vid() {
+        let mut e = blank_entry(HASH);
+        e.media_key = Some([0x33u8; 16]);
+        e.unit_keys = vec![(1, [0x55u8; 16])];
+        let db = db_with(e, Vec::new());
+        let r = KeydbSource::resolve_from(&db, &ctx(HASH, vec![[0x44u8; 16]; 2], None));
+        assert_eq!(r.keys.len(), 1, "the stored key");
+        assert_eq!(r.miss_path, vec![KeyNode::NoVid]);
+    }
+
     // A hash that is NOT in the keydb is the one true miss: not matched, no
     // shape, no miss path (the library renders this as `no entry`).
     #[test]