Heroku needs ruby

Gemfile

@@ -1,5 +1,7 @@
 source "https://rubygems.org"
 
+ruby "3.4.1"
+
 # Bundle edge Rails instead: gem "rails", github: "rails/rails", branch: "main"
 gem "rails", "~> 8.0.1"
 # The modern asset pipeline for Rails [https://github.com/rails/propshaft]

Gemfile.lock

@@ -474,5 +474,8 @@ DEPENDENCIES
   tzinfo-data
   web-console
 
+RUBY VERSION
+   ruby 3.4.1p0
+
 BUNDLED WITH
    2.6.2

spec/routing/topics_routing_spec.rb

@@ -0,0 +1,37 @@
+require "rails_helper"
+
+RSpec.describe TopicsController, type: :routing do
+  describe "routing" do
+    it "routes to #index" do
+      expect(get: "/topics").to route_to("topics#index")
+    end
+
+    it "routes to #new" do
+      expect(get: "/topics/new").to route_to("topics#new")
+    end
+
+    it "routes to #show" do
+      expect(get: "/topics/1").to route_to("topics#show", id: "1")
+    end
+
+    it "routes to #edit" do
+      expect(get: "/topics/1/edit").to route_to("topics#edit", id: "1")
+    end
+
+    it "routes to #create" do
+      expect(post: "/topics").to route_to("topics#create")
+    end
+
+    it "routes to #update via PUT" do
+      expect(put: "/topics/1").to route_to("topics#update", id: "1")
+    end
+
+    it "routes to #update via PATCH" do
+      expect(patch: "/topics/1").to route_to("topics#update", id: "1")
+    end
+
+    it "routes to #destroy" do
+      expect(delete: "/topics/1").to route_to("topics#destroy", id: "1")
+    end
+  end
+end