From 5fb6ec581cdb0f189a1c62b9a496d8522fa13a6f Mon Sep 17 00:00:00 2001
From: Mauro Lacy <mauro@lacy.com.es>
Date: Wed, 27 Oct 2021 15:06:06 +0200
Subject: [PATCH] Fix: `MultiIndex` key deserializes to remaining key plus pk
 (`Map`-like)

---
 packages/storage-plus/src/indexed_map.rs | 65 ++++++++++++++++++++++++
 packages/storage-plus/src/indexes.rs     |  5 +-
 2 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/packages/storage-plus/src/indexed_map.rs b/packages/storage-plus/src/indexed_map.rs
index d4ffeed96..f6f1affef 100644
--- a/packages/storage-plus/src/indexed_map.rs
+++ b/packages/storage-plus/src/indexed_map.rs
@@ -684,6 +684,71 @@ mod test {
         assert_eq!(data3, marias[1].1);
     }
 
+    #[test]
+    fn range_de_composite_key_by_multi_index() {
+        let mut store = MockStorage::new();
+
+        let indexes = DataCompositeMultiIndex {
+            name_age: MultiIndex::new(
+                |d, k| index_triple(&d.name, d.age, k),
+                "data",
+                "data__name_age",
+            ),
+        };
+        let map = IndexedMap::new("data", indexes);
+
+        // save data
+        let data1 = Data {
+            name: "Maria".to_string(),
+            last_name: "".to_string(),
+            age: 42,
+        };
+        let pk1: &[u8] = b"5627";
+        map.save(&mut store, pk1, &data1).unwrap();
+
+        let data2 = Data {
+            name: "Juan".to_string(),
+            last_name: "Perez".to_string(),
+            age: 13,
+        };
+        let pk2: &[u8] = b"5628";
+        map.save(&mut store, pk2, &data2).unwrap();
+
+        let data3 = Data {
+            name: "Maria".to_string(),
+            last_name: "Young".to_string(),
+            age: 24,
+        };
+        let pk3: &[u8] = b"5629";
+        map.save(&mut store, pk3, &data3).unwrap();
+
+        let data4 = Data {
+            name: "Maria Luisa".to_string(),
+            last_name: "Bemberg".to_string(),
+            age: 43,
+        };
+        let pk4: &[u8] = b"5630";
+        map.save(&mut store, pk4, &data4).unwrap();
+
+        let marias: Vec<_> = map
+            .idx
+            .name_age
+            .sub_prefix_de(b"Maria".to_vec())
+            .range_de(&store, None, None, Order::Descending)
+            .collect::<StdResult<_>>()
+            .unwrap();
+        let count = marias.len();
+        assert_eq!(2, count);
+
+        // Remaining age of the index keys, plus pks (sorted by age descending)
+        assert_eq!((42, pk1.to_vec()), marias[0].0);
+        assert_eq!((24, pk3.to_vec()), marias[1].0);
+
+        // Data
+        assert_eq!(data1, marias[0].1);
+        assert_eq!(data3, marias[1].1);
+    }
+
     #[test]
     fn unique_index_enforced() {
         let mut store = MockStorage::new();
diff --git a/packages/storage-plus/src/indexes.rs b/packages/storage-plus/src/indexes.rs
index 1a07353f9..bdbfc11e5 100644
--- a/packages/storage-plus/src/indexes.rs
+++ b/packages/storage-plus/src/indexes.rs
@@ -123,7 +123,8 @@ fn deserialize_multi_v<T: DeserializeOwned>(
         .ok_or_else(|| StdError::generic_err("pk not found"))?;
     let v = from_slice::<T>(&v)?;
 
-    Ok((pk.into(), v))
+    // FIXME: Return `key` here instead of `pk` (be consistent with `deserialize_multi_kv` and `Map` behaviour)
+    Ok((pk.to_vec(), v))
 }
 
 fn deserialize_multi_kv<K: KeyDeserialize, T: DeserializeOwned>(
@@ -147,7 +148,7 @@ fn deserialize_multi_kv<K: KeyDeserialize, T: DeserializeOwned>(
         .ok_or_else(|| StdError::generic_err("pk not found"))?;
     let v = from_slice::<T>(&v)?;
 
-    Ok((K::from_vec(pk.to_vec())?, v))
+    Ok((K::from_vec(key)?, v))
 }
 
 impl<'a, K, T> Index<T> for MultiIndex<'a, K, T>