Fix false positive in MultiAliasImportRequireUseTest

Refs #1117

Author: rrrene

lib/credo/check/consistency/multi_alias_import_require_use/collector.ex

@@ -33,6 +33,10 @@ defmodule Credo.Check.Consistency.MultiAliasImportRequireUse.Collector do
     {ast, {Map.put(acc, mod_name, []), mod_name}}
   end
 
+  defp traverse({op, _, _}, acc) when op in [:def, :defp] do
+    {nil, acc}
+  end
+
   defp traverse({directive, meta, arguments} = ast, {acc, current_module})
        when directive in @directives and not is_nil(current_module) do
     aliases =

test/credo/check/consistency/multi_alias_import_require_use_test.exs

@@ -110,4 +110,35 @@ defmodule Credo.Check.Consistency.MultiAliasImportRequireUseTest do
       assert issue.trigger == ""
     end)
   end
+
+  test "it should not report errors when #1117" do
+    [
+      ~S'''
+      defmodule A.B.Foo do
+        alias A.{B, C}
+      end
+      ''',
+      ~S'''
+      defmodule SomeModule do
+        @moduledoc false
+
+        alias A.B.Foo
+
+        case Application.compile_env(:app, SomeModule)[:use_bar] do
+          "true" ->
+            defp a do
+              alias A.B.Bar
+              Bar.f()
+            end
+
+          _ ->
+            defp a, do: nil
+        end
+      end
+      '''
+    ]
+    |> to_source_files
+    |> run_check(@described_check)
+    |> refute_issues()
+  end
 end