feat: add partial storage key support

frame_metadata/Key.test.ts

@@ -15,6 +15,11 @@ Deno.test("System Accounts Key", async () => {
     pallet,
     storageEntry,
   });
+  const partialKey: unknown[] = [];
+  assertEquals(
+    U.hex.encode($key.encode(partialKey)),
+    "26aa394eea5630e07c48ae0c9558cef7b99d880ec681799c0cf30e8886371da9",
+  );
   const key = [t.alice.publicKey];
   const encoded = $key.encode(key);
   assertEquals(
@@ -42,3 +47,21 @@ Deno.test("Auction Winning Key", async () => {
   const decoded = $key.decode(encoded);
   assertEquals(key, decoded);
 });
+
+Deno.test("Multisig Multisigs partial storage Key", async () => {
+  const [metadata, deriveCodec] = await setup("polkadot");
+  const [pallet, storageEntry] = U.throwIfError(
+    getPalletAndEntry(metadata, "Multisig", "Multisigs"),
+  );
+  const $key = $storageKey({
+    deriveCodec,
+    pallet,
+    storageEntry,
+  });
+  const key = [t.alice.publicKey];
+  const encoded = $key.encode(key);
+  assertEquals(
+    U.hex.encode(encoded),
+    "7474449cca95dc5d0c00e71735a6d17d3cd15a3fd6e04e47bee3922dbfa92c8d518366b5b1bc7c99d43593c715fdd31c61141abd04a99fd6822c8558854ccde39a5684e7a56da27d",
+  );
+});

frame_metadata/Key.ts

@@ -28,23 +28,30 @@ export function $storageKey(props: StorageKeyProps): $.Codec<unknown[]> {
   }
   const palletHash = H.Twox128.hash(new TextEncoder().encode(props.pallet.name));
   const entryHash = H.Twox128.hash(new TextEncoder().encode(props.storageEntry.name));
-  const $keys = $.tuple(
-    ...keyCodecs.map(($key, i) =>
-      H[(props.storageEntry as M.MapStorageEntryType).hashers[i]!].$hash($key)
-    ),
+  const $keys = [...Array(keyCodecs.length + 1).keys()].reduce(
+    (keys, i) => {
+      keys[i] = $.tuple(
+        ...keyCodecs.slice(0, i).map(($key, i) =>
+          H[(props.storageEntry as M.MapStorageEntryType).hashers[i]!].$hash($key)
+        ),
+      );
+      return keys;
+    },
+    {} as Record<number, $.Codec<any[]>>,
   );
   return $.createCodec({
     _metadata: [$storageKey, props],
-    _staticSize: $keys._staticSize,
+    _staticSize: $keys[Object.values($keys).length - 1]!._staticSize,
     _encode(buffer, key) {
       buffer.insertArray(palletHash);
       buffer.insertArray(entryHash);
-      $keys._encode(buffer, key);
+      if (key.length === 0) return;
+      $keys[key.length]!._encode(buffer, key);
     },
     _decode(buffer) {
       // Ignore initial hashes
       buffer.index += 32;
-      return $keys._decode(buffer);
+      return $keys[Object.values($keys).length - 1]!._decode(buffer);
     },
   });
 }

words.txt

@@ -175,3 +175,4 @@ trufflesecurity
 tailaiw
 trufflehog
 amannn
+multisigs