Fix Nesting issues with non-do blocks

Refs #1029

lib/credo/check/refactor/nesting.ex

@@ -86,9 +86,12 @@ defmodule Credo.Check.Refactor.Nesting do
   defp find_depth(arguments, nest_list, line_no, trigger)
        when is_list(arguments) do
     arguments
-    |> Credo.Code.Block.do_block_for!()
-    |> List.wrap()
-    |> Enum.map(&find_depth(&1, nest_list, line_no, trigger))
+    |> Credo.Code.Block.all_blocks_for!()
+    |> Enum.flat_map(fn block ->
+      block
+      |> List.wrap()
+      |> Enum.map(&find_depth(&1, nest_list, line_no, trigger))
+    end)
     |> Enum.sort()
     |> List.last()
   end

test/credo/check/refactor/nesting_test.exs

@@ -170,4 +170,27 @@ defmodule Credo.Check.Refactor.NestingTest do
     |> run_check(@described_check)
     |> assert_issue()
   end
+
+  test "it should report a violation /6" do
+    """
+    defmodule CredoSampleModule do
+      defp foo() do
+        if true do
+          "flat"
+        else
+          if true do
+            if true do
+              if true do
+                "nested"
+              end
+            end
+          end
+        end
+      end
+    end
+    """
+    |> to_source_file
+    |> run_check(@described_check)
+    |> assert_issue()
+  end
 end