Mark methods called by MiniTest.setup as alive

Signed-off-by: Alexandre Terrasa <alexandre.terrasa@shopify.com>

lib/spoom/deadcode/plugins/minitest.rb

@@ -22,6 +22,15 @@ class Minitest < Base
         def on_define_method(indexer, definition)
           definition.ignored! if indexer.path.match?(%r{test/.*test\.rb$}) && definition.name.match?(/^test_/)
         end
+
+        sig { override.params(indexer: Indexer, send: Send).void }
+        def on_send(indexer, send)
+          return unless send.recv.nil? && send.name == "setup"
+
+          send.each_arg(SyntaxTree::SymbolLiteral) do |arg|
+            indexer.reference_method(indexer.node_string(arg.value), send.node)
+          end
+        end
       end
     end
   end

test/spoom/deadcode/plugins/minitest_test.rb

@@ -57,6 +57,24 @@ def some_other_test; end
           refute_ignored(index, "some_other_test")
         end
 
+        def test_ignore_minitest_setup_with_symbol
+          @project.write!("test/foo_test.rb", <<~RB)
+            class FooTest
+              setup(:alive1)
+              setup(:alive2)
+
+              def alive1; end
+              def alive2; end
+              def dead; end
+            end
+          RB
+
+          index = index_with_plugins
+          assert_alive(index, "alive1")
+          assert_alive(index, "alive2")
+          assert_dead(index, "dead")
+        end
+
         private
 
         sig { returns(Deadcode::Index) }