Merge PR #43611

Squashed commit of the following:

    Tweaks

    Extend test adding more assertions

    Update scaffold generator test and add application generator test for controller generator with namespace

    Adapt code to feedback suggestions

    Apply suggestions from code review

    Run generated tests by scaffold controller generator

    Fix generated tests too

    Keep generated url helpers consistent

    Fix scaffold controller generator with namespace

    For example:

    ```
    bundle exec rails g scaffold_controller Admin::Post title:string content:text --model-name=Post
    ```

    It fixes the code generated by railties, other changes are required on
    jbuilder gem.

Co-authored-by: Jonathan Hefner <jonathan@hefner.pro>
Co-authored-by: José Galisteo <ceritium@gmail.com>

railties/lib/rails/generators/erb/scaffold/templates/edit.html.erb.tt

@@ -5,6 +5,6 @@
 <br>
 
 <div>
-  <%%= link_to "Show this <%= human_name.downcase %>", @<%= singular_table_name %> %> |
-  <%%= link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper %>_path %>
+  <%%= link_to "Show this <%= human_name.downcase %>", <%= model_resource_name(prefix: "@") %> %> |
+  <%%= link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper(type: :path) %> %>
 </div>

railties/lib/rails/generators/erb/scaffold/templates/index.html.erb.tt

@@ -6,9 +6,9 @@
   <%% @<%= plural_table_name %>.each do |<%= singular_table_name %>| %>
     <%%= render <%= singular_table_name %> %>
     <p>
-      <%%= link_to "Show this <%= human_name.downcase %>", <%= singular_name %> %>
+      <%%= link_to "Show this <%= human_name.downcase %>", <%= model_resource_name(singular_name) %> %>
     </p>
   <%% end %>
 </div>
 
-<%%= link_to "New <%= human_name.downcase %>", new_<%= singular_route_name %>_path %>
+<%%= link_to "New <%= human_name.downcase %>", <%= new_helper(type: :path) %> %>

railties/lib/rails/generators/erb/scaffold/templates/new.html.erb.tt

@@ -5,5 +5,5 @@
 <br>
 
 <div>
-  <%%= link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper %>_path %>
+  <%%= link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper(type: :path) %> %>
 </div>

railties/lib/rails/generators/erb/scaffold/templates/show.html.erb.tt

@@ -3,8 +3,8 @@
 <%%= render @<%= singular_table_name %> %>
 
 <div>
-  <%%= link_to "Edit this <%= human_name.downcase %>", edit_<%= singular_table_name %>_path(@<%= singular_table_name %>) %> |
-  <%%= link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper %>_path %>
+  <%%= link_to "Edit this <%= human_name.downcase %>", <%= edit_helper(type: :path) %> %> |
+  <%%= link_to "Back to <%= human_name.pluralize.downcase %>", <%= index_helper(type: :path) %> %>
 
-  <%%= button_to "Destroy this <%= human_name.downcase %>", <%= singular_table_name %>_path(@<%= singular_table_name %>), method: :delete %>
+  <%%= button_to "Destroy this <%= human_name.downcase %>", <%= show_helper(type: :path) %>, method: :delete %>
 </div>

railties/lib/rails/generators/named_base.rb

@@ -94,20 +94,20 @@ def uncountable? # :doc:
           singular_name == plural_name
         end
 
-        def index_helper # :doc:
-          uncountable? ? "#{plural_route_name}_index" : plural_route_name
+        def index_helper(type: nil) # :doc:
+          [plural_route_name, ("index" if uncountable?), type].compact.join("_")
         end
 
-        def show_helper # :doc:
-          "#{singular_route_name}_url(@#{singular_table_name})"
+        def show_helper(arg = "@#{singular_table_name}", type: :url) # :doc:
+          "#{singular_route_name}_#{type}(#{arg})"
         end
 
-        def edit_helper # :doc:
-          "edit_#{show_helper}"
+        def edit_helper(...) # :doc:
+          "edit_#{show_helper(...)}"
         end
 
-        def new_helper # :doc:
-          "new_#{singular_route_name}_url"
+        def new_helper(type: :url) # :doc:
+          "new_#{singular_route_name}_#{type}"
         end
 
         def singular_table_name # :doc:
@@ -147,8 +147,8 @@ def redirect_resource_name # :doc:
           model_resource_name(prefix: "@")
         end
 
-        def model_resource_name(prefix: "") # :doc:
-          resource_name = "#{prefix}#{singular_table_name}"
+        def model_resource_name(model = singular_table_name, prefix: "") # :doc:
+          resource_name = "#{prefix}#{model}"
           if options[:model_name]
             "[#{controller_class_path.map { |name| ":" + name }.join(", ")}, #{resource_name}]"
           else

railties/lib/rails/generators/test_unit/scaffold/templates/functional_test.rb.tt

@@ -11,7 +11,7 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
   end
 
   test "should get index" do
-    get <%= index_helper %>_url
+    get <%= index_helper(type: :url) %>
     assert_response :success
   end
 
@@ -22,10 +22,10 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
 
   test "should create <%= singular_table_name %>" do
     assert_difference("<%= class_name %>.count") do
-      post <%= index_helper %>_url, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
+      post <%= index_helper(type: :url) %>, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
     end
 
-    assert_redirected_to <%= singular_table_name %>_url(<%= class_name %>.last)
+    assert_redirected_to <%= show_helper("#{class_name}.last") %>
   end
 
   test "should show <%= singular_table_name %>" do
@@ -40,15 +40,15 @@ class <%= controller_class_name %>ControllerTest < ActionDispatch::IntegrationTe
 
   test "should update <%= singular_table_name %>" do
     patch <%= show_helper %>, params: { <%= "#{singular_table_name}: { #{attributes_string} }" %> }
-    assert_redirected_to <%= singular_table_name %>_url(<%= "@#{singular_table_name}" %>)
+    assert_redirected_to <%= show_helper %>
   end
 
   test "should destroy <%= singular_table_name %>" do
     assert_difference("<%= class_name %>.count", -1) do
       delete <%= show_helper %>
     end
 
-    assert_redirected_to <%= index_helper %>_url
+    assert_redirected_to <%= index_helper(type: :url) %>
   end
 end
 <% end -%>

railties/test/generators/scaffold_controller_generator_test.rb

@@ -221,16 +221,41 @@ def test_model_name_option
     end
 
     assert_file "app/views/admin/users/index.html.erb" do |content|
-      assert_match("\"New user\", new_admin_user_path", content)
+      assert_match(%{"New user", new_admin_user_path}, content)
     end
 
     assert_file "app/views/admin/users/new.html.erb" do |content|
-      assert_match("\"Back to users\", admin_users_path", content)
+      assert_match(%{"Back to users", admin_users_path}, content)
+    end
+
+    assert_file "app/views/admin/users/edit.html.erb" do |content|
+      assert_match(%{"Show this user", [:admin, @user]}, content)
+      assert_match(%{"Back to users", admin_users_path}, content)
+    end
+
+    assert_file "app/views/admin/users/show.html.erb" do |content|
+      assert_match(%{"Edit this user", edit_admin_user_path(@user)}, content)
+      assert_match(%{"Back to users", admin_users_path}, content)
+      assert_match(%{"Destroy this user", admin_user_path(@user)}, content)
     end
 
     assert_file "app/views/admin/users/_form.html.erb" do |content|
       assert_match("model: [:admin, user]", content)
     end
+
+    assert_file "app/views/admin/users/_user.html.erb" do |content|
+      assert_match(%{"Show this user", [:admin, user]}, content)
+    end
+
+    assert_file "test/controllers/admin/users_controller_test.rb" do |content|
+      assert_match " admin_users_url", content
+      assert_match " new_admin_user_url", content
+      assert_match " edit_admin_user_url", content
+      assert_match " admin_user_url(@user)", content
+      assert_no_match %r/\b(new_|edit_)?users?_(path|url)/, content
+    end
+
+    assert_file "test/system/users_test.rb"
   end
 
   def test_controller_tests_pass_by_default_inside_mountable_engine