Add data attributes to summary list rows

This allows users to add data attributes (for example, when initialising
Javascript modules) to individual rows

app/views/govuk_publishing_components/components/_summary_list.html.erb

@@ -77,7 +77,7 @@
               classes = "govuk-summary-list__row"
             end
           %>
-          <%= tag.div class: classes do %>
+          <%= tag.div class: classes, data: item[:data_attributes] do %>
 
             <%= tag.dt item[:field], class: "govuk-summary-list__key" %>
             <%= tag.dd item[:value], class: "govuk-summary-list__value" %>

app/views/govuk_publishing_components/components/docs/summary_list.yml

@@ -139,6 +139,17 @@ examples:
         edit:
           href: "edit-feedback"
 
+  with_data_attributes:
+    description: |
+      Data attributes can be passed to individual items within the component as shown.
+    data:
+      title: "Title, summary and body"
+      items:
+        - field: "Title"
+          value: "Ethical standards for public service providers"
+          data_attributes:
+            module: "something"
+
   with_block:
     description: Use the summary list with a block when you need to show an empty state message or load another component.
     data:

spec/components/summary_list_spec.rb

@@ -306,4 +306,19 @@ def component_name
     )
     assert_select(".gem-c-summary-list.gem-c-summary-list--wide-title")
   end
+
+  it "renders component with row data attributes" do
+    render_component(
+      title: "Title",
+      items: [
+        {
+          field: "One",
+          value: "Value 1",
+          data_attributes: { module: "something" },
+        },
+      ],
+    )
+
+    assert_select ".govuk-summary-list__row[data-module='something']", text: /One/
+  end
 end