From 515f29330f810667b61fdeb8bd9f41b3dd841fc1 Mon Sep 17 00:00:00 2001
From: nikitosing <nikitosing4@mail.ru>
Date: Mon, 26 Jul 2021 16:10:19 +0700
Subject: [PATCH] Fix error response in contract's output

---
 CHANGELOG.md                                       |  1 +
 .../smart_contract/_function_response.html.eex     | 14 +++++++++-----
 .../block_scout_web/views/smart_contract_view.ex   |  2 ++
 .../explorer/lib/explorer/smart_contract/reader.ex | 11 ++++++++---
 .../test/explorer/smart_contract/reader_test.exs   |  6 ++++++
 5 files changed, 26 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2e8d0db64a..79189a3add 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@
 - [#4401](https://github.com/blockscout/blockscout/pull/4401) - Fix displaying of token holders with the same amount
 
 ### Chore
+- [#4439](https://github.com/blockscout/blockscout/pull/4439) - Fix revert response in contract's output
 
 
 ## 3.7.2-beta
diff --git a/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_function_response.html.eex b/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_function_response.html.eex
index a6110cc3d3..3f82cef96f 100644
--- a/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_function_response.html.eex
+++ b/apps/block_scout_web/lib/block_scout_web/templates/smart_contract/_function_response.html.eex
@@ -1,10 +1,14 @@
 <div class="tile tile-muted tile-function-response monospace">
 <pre>
 [ <strong><%= @function_name %></strong> method Response ]
-
-[<%= for item <- @outputs do %>
-<%= if named_argument?(item) do %><span class="function-response-item"><%= item["name"] %></span><% end %>
-<span class="text-muted"><%= raw(values_with_type(item["value"], item["type"])) %></span>
-<% end %>]
+<%= case @outputs do %>
+    <% {:error, message} -> %>
+        <span class="text-muted"><%=raw(values_with_type(message, :error))%></span>
+    <% _ -> %>
+        [<%= for item <- @outputs do %>
+            <%= if named_argument?(item) do %><span class="function-response-item"><%= item["name"] %></span><% end %>
+            <span class="text-muted"><%= raw(values_with_type(item["value"], item["type"])) %></span>
+        <% end %>]
+<% end %>
 </pre>
 </div>
diff --git a/apps/block_scout_web/lib/block_scout_web/views/smart_contract_view.ex b/apps/block_scout_web/lib/block_scout_web/views/smart_contract_view.ex
index d75ba3a24e..2705acf2de 100644
--- a/apps/block_scout_web/lib/block_scout_web/views/smart_contract_view.ex
+++ b/apps/block_scout_web/lib/block_scout_web/views/smart_contract_view.ex
@@ -100,6 +100,8 @@ defmodule BlockScoutWeb.SmartContractView do
 
   def values_with_type(value, :bool, _components), do: render_type_value("bool", to_string(value))
 
+  def values_with_type(value, :error, _components), do: render_type_value("error", value)
+
   def values_with_type(value, type, _components) do
     render_type_value(type, binary_to_utf_string(value))
   end
diff --git a/apps/explorer/lib/explorer/smart_contract/reader.ex b/apps/explorer/lib/explorer/smart_contract/reader.ex
index 1a36a35ce6..7c244cb7f4 100644
--- a/apps/explorer/lib/explorer/smart_contract/reader.ex
+++ b/apps/explorer/lib/explorer/smart_contract/reader.ex
@@ -450,10 +450,15 @@ defmodule Explorer.SmartContract.Reader do
 
   def link_outputs_and_values(blockchain_values, outputs, method_id) do
     default_value = Enum.map(outputs, fn _ -> "" end)
-    {_, value} = Map.get(blockchain_values, method_id, {:ok, default_value})
 
-    for {output, index} <- Enum.with_index(outputs) do
-      new_value(output, List.wrap(value), index)
+    case Map.get(blockchain_values, method_id, {:ok, default_value}) do
+      {:ok, value} ->
+        for {output, index} <- Enum.with_index(outputs) do
+          new_value(output, List.wrap(value), index)
+        end
+
+      {:error, message} ->
+        {:error, message}
     end
   end
 
diff --git a/apps/explorer/test/explorer/smart_contract/reader_test.exs b/apps/explorer/test/explorer/smart_contract/reader_test.exs
index d6b4ce5cc5..3b9fb2d053 100644
--- a/apps/explorer/test/explorer/smart_contract/reader_test.exs
+++ b/apps/explorer/test/explorer/smart_contract/reader_test.exs
@@ -357,6 +357,12 @@ defmodule Explorer.SmartContract.ReaderTest do
                }
              ] = Reader.link_outputs_and_values(blockchain_values, outputs, function_name)
     end
+
+    test "save error message" do
+      blockchain_values = %{"check" => {:error, "Reverted"}}
+
+      assert {:error, "Reverted"} == Reader.link_outputs_and_values(blockchain_values, [], "check")
+    end
   end
 
   defp blockchain_get_function_mock do