graph/db: fix address fetching error

graph/db/graph_test.go

@@ -190,17 +190,7 @@ func TestNodeInsertionAndDeletion(t *testing.T) {
 	// Fetch the node and assert the empty addresses.
 	dbNode, err = graph.FetchLightningNode(ctx, testPub)
 	require.NoError(t, err)
-
-	// Temporarily have a special case for SQLStore, as currently, it does
-	// not correctly handle empty addresses. We assert this incorrect
-	// behaviour here in order to demonstrate the bug. This will be fixed in
-	// an upcoming commit.
-	if _, ok := graph.V1Store.(*SQLStore); ok {
-		require.Empty(t, dbNode.Addresses)
-		require.NotEqual(t, node.Addresses, dbNode.Addresses)
-	} else {
-		compareNodes(t, node, dbNode)
-	}
+	compareNodes(t, node, dbNode)
 
 	known, addrs, err = graph.AddrsForNode(ctx, pub)
 	require.NoError(t, err)

graph/db/sql_store.go

@@ -3619,6 +3619,12 @@ func getNodeAddresses(ctx context.Context, db SQLQueries, nodePub []byte) (bool,
 		}
 	}
 
+	// If we have no addresses, then we'll return nil instead of an
+	// empty slice.
+	if len(addresses) == 0 {
+		addresses = nil
+	}
+
 	return true, addresses, nil
 }