Display shortened addresses in named address links (#839)

* Display shortened addresses in named address links
* Simplify HTML for named address links

apps/block_scout_web/lib/block_scout_web/templates/address/_responsive_hash.html.eex

@@ -1,7 +1,6 @@
 <span class="<%= if @contract do %>contract-address<% end %>" data-address-hash="<%= @address.hash %>">
   <%= if name = primary_name(@address) do %>
-    <span class="d-none d-md-none d-lg-inline" data-toggle="tooltip" data-placement="top" title="<%= @address.hash %>"><%= name %></span>
-    <span class="d-md-inline-block d-lg-none " data-toggle="tooltip" data-placement="top" title="<%= @address.hash %>"><%= name %></span>
+    <span data-toggle="tooltip" data-placement="top" title="<%= @address.hash %>"><%= name %> (<%= short_hash(@address) %>...)</span>
   <% else %>
     <%= if assigns[:truncate] do %>
       <%= BlockScoutWeb.AddressView.trimmed_hash(@address.hash) %>

apps/block_scout_web/lib/block_scout_web/views/address_view.ex

@@ -219,4 +219,14 @@ defmodule BlockScoutWeb.AddressView do
   defp tab_name(["internal_transactions"]), do: gettext("Internal Transactions")
   defp tab_name(["contracts"]), do: gettext("Code")
   defp tab_name(["read_contract"]), do: gettext("Read Contract")
+
+  def short_hash(%Address{hash: hash}) do
+    <<
+      "0x",
+      short_address::binary-size(6),
+      _rest::binary
+    >> = to_string(hash)
+
+    "0x" <> short_address
+  end
 end

apps/block_scout_web/test/block_scout_web/views/address_view_test.exs

@@ -321,4 +321,12 @@ defmodule BlockScoutWeb.AddressViewTest do
       assert AddressView.current_tab_name(path) == "Read Contract"
     end
   end
+
+  describe "short_hash/1" do
+    test "returns a shortened hash of 6 hex characters" do
+      address = insert(:address)
+      assert "0x" <> short_hash = AddressView.short_hash(address)
+      assert String.length(short_hash) == 6
+    end
+  end
 end