Add deadcode plugin handling for Object#method

Signed-off-by: Alexandre Terrasa <[email protected]>

lib/spoom/deadcode/plugins/ruby.rb

@@ -34,6 +34,9 @@ def on_send(send)
             if last_arg.is_a?(Prism::SymbolNode) || last_arg.is_a?(Prism::StringNode)
               @index.reference_method(last_arg.unescaped, send.location)
             end
+          when "method"
+            arg = send.args.first
+            @index.reference_method(arg.unescaped, send.location) if arg.is_a?(Prism::SymbolNode)
           end
         end
 

test/spoom/deadcode/plugins/ruby_test.rb

@@ -163,6 +163,23 @@ def test_alive_constants_with_const_source_location
           assert_dead(index, "DEAD")
         end
 
+        def test_alive_methods_with_method
+          @project.write!("foo.rb", <<~RB)
+            def alive1; end
+            def alive2; end
+
+            def dead; end
+
+            method :alive1
+            [].map(&method(:alive2))
+          RB
+
+          index = index_with_plugins
+          assert_alive(index, "alive1")
+          assert_alive(index, "alive2")
+          assert_dead(index, "dead")
+        end
+
         private
 
         sig { returns(Deadcode::Index) }