fix(queryresult): check location claim shard multihash (#272)

# Goals

Ooops... yea all we're doing for compressed queries is looking for a
locaiton claim, but not checking its for the right shard. When there are
multiple, bad things happen

Author: hannahhoward

pkg/service/queryresult/queryresult.go

@@ -179,7 +179,7 @@ func BuildCompressed(targetMh mh.Multihash, principal ucan.Signer, claims map[ci
 	}
 
 	for _, index := range indexes.Iterator() {
-		for _, shard := range index.Shards().Iterator() {
+		for shardHash, shard := range index.Shards().Iterator() {
 			if shard.Has(targetMh) {
 				pos := shard.Get(targetMh)
 				hasLocation := false
@@ -190,6 +190,10 @@ func BuildCompressed(targetMh mh.Multihash, principal ucan.Signer, claims map[ci
 					if err != nil {
 						continue
 					}
+					if match.Value().Nb().Content.Hash().B58String() != shardHash.B58String() {
+						continue
+					}
+
 					hasLocation = true
 
 					locClaim = match.Value().Nb()

pkg/service/queryresult/queryresult_test.go

@@ -74,9 +74,29 @@ func TestBuildCompressed(t *testing.T) {
 		)
 		require.NoError(t, err)
 
+		otherLocationURL, err := url.Parse("https://example2.com/shard.car")
+		require.NoError(t, err)
+		otherShardMH := testutil.RandomMultihash(t)
+		otherShardLength := uint64(8000)
+		otherShardClaim, err := assert.Location.Delegate(
+			principal,
+			principal,
+			principal.DID().String(),
+			assert.LocationCaveats{
+				Content:  ctypes.FromHash(otherShardMH),
+				Location: []url.URL{*otherLocationURL},
+				Range: &assert.Range{
+					Offset: 1000, // The shard starts at offset 1000
+					Length: &otherShardLength,
+				},
+			},
+		)
+		require.NoError(t, err)
+
 		// Build the claims map
 		claims := map[cid.Cid]delegation.Delegation{
-			link.ToCID(shardClaim.Link()): shardClaim,
+			link.ToCID(otherShardClaim.Link()): otherShardClaim,
+			link.ToCID(shardClaim.Link()):      shardClaim,
 		}
 
 		// Build the indexes map