Fix a bug when nesting attributes more than two levels with hashes

lib/phlex/sgml.rb

@@ -518,7 +518,7 @@ def __nested_attributes__(attributes, base_name, buffer = +"")
 			when Integer, Float
 				buffer << " " << base_name << name << '="' << v.to_s << '"'
 			when Hash
-				__nested_attributes__(v, "#{base_name}-#{name}-", buffer)
+				__nested_attributes__(v, "#{base_name}#{name}-", buffer)
 			when Array
 				buffer << " " << base_name << name << '="' << __nested_tokens__(v) << '"'
 			when Set

quickdraw/sgml/attributes.test.rb

@@ -50,4 +50,24 @@
 
 		expect(example.call) == %(<#{tag} data-controller="foo" data-turbo-action="delete">content</#{tag}>)
 	end
+
+	test "<#{tag}> with nil attributes" do
+		example = Class.new(Phlex::HTML) do
+			define_method :view_template do
+				__send__(method_name, class: nil, style: nil, data: { controller: nil }) { "content" }
+			end
+		end
+
+		expect(example.call) == %(<#{tag}>content</#{tag}>)
+	end
+
+	test "<#{tag}> with deeply nested attributes" do
+		example = Class.new(Phlex::HTML) do
+			define_method :view_template do
+				__send__(method_name, data: { controller: "foo", foo: { comments_outlet: "#comments" } }) { "content" }
+			end
+		end
+
+		expect(example.call) == %(<#{tag} data-controller="foo" data-foo-comments-outlet="#comments">content</#{tag}>)
+	end
 end