Read contract: fix internal server error for method with empty output array

CHANGELOG.md

@@ -7,6 +7,7 @@
 - [#3462](https://github.com/poanetwork/blockscout/pull/3462) - Display price for bridged tokens
 
 ### Fixes
+- [#3514](https://github.com/poanetwork/blockscout/pull/3514) - Read contract: fix internal server error
 - [#3513](https://github.com/poanetwork/blockscout/pull/3513) - Fix input data processing for method call (array type of data)
 - [#3509](https://github.com/poanetwork/blockscout/pull/3509) - Fix QR code tooltip appearance in mobile view
 - [#3507](https://github.com/poanetwork/blockscout/pull/3507), [#3510](https://github.com/poanetwork/blockscout/pull/3510) - Fix left margin of balance card in mobile view

apps/explorer/lib/explorer/smart_contract/reader.ex

@@ -454,6 +454,8 @@ defmodule Explorer.SmartContract.Reader do
     if String.contains?(number_rest, "[]") do
       values_array = Enum.at(values, index)
 
+      values_array = if is_list(values_array), do: values_array, else: []
+
       values_array_formatted =
         Enum.map(values_array, fn value ->
           bytes_to_string(value)