Test multiple formats

test.rb

@@ -37,6 +37,11 @@ cmd :REGISTER_FORMAT, { name: :html,
                         args: ['test/render.rb',
                                { template: nil },
                                { format: nil }] }
+cmd :REGISTER_FORMAT, { name: :json,
+                        stdin: { notes: nil },
+                        args: ['test/render.rb',
+                               { template: nil },
+                               { format: nil }] }
 
 cmd :ADD_REF,
     { kind: :self,
@@ -119,3 +124,55 @@ cmd(:RENDER_FOOTNOTES, :html).tap do |result|
 
   raise unless result == expected
 end
+cmd(:RENDER_FOOTNOTES, :json).tap do |result|
+  expected = <<~JSON.freeze
+    {
+      "self": [
+        {
+          "index": 1,
+          "kind": "self",
+          "id": "/blog/foo",
+          "slug": "blog-foo",
+          "anchor": "self-blog-foo",
+          "fragment": "#self-blog-foo",
+          "url": "/blog/foo.html",
+          "text": "Foo"
+        },
+        {
+          "index": 3,
+          "kind": "self",
+          "id": "/blog/bar",
+          "slug": "blog-bar",
+          "anchor": "self-blog-bar",
+          "fragment": "#self-blog-bar",
+          "url": "/blog/bar.html",
+          "text": "Bar"
+        }
+      ],
+      "link": [
+        {
+          "index": 2,
+          "kind": "link",
+          "id": "example_com",
+          "slug": "example-com",
+          "anchor": "link-example-com",
+          "fragment": "#link-example-com",
+          "url": "https://example.com",
+          "text": "Example Domain"
+        },
+        {
+          "index": 4,
+          "kind": "link",
+          "id": "causa_arcana_com",
+          "slug": "causa-arcana-com",
+          "anchor": "link-causa-arcana-com",
+          "fragment": "#link-causa-arcana-com",
+          "url": "https://causa-arcana.com",
+          "text": "Causa Arcana"
+        }
+      ]
+    }
+  JSON
+
+  raise unless result == expected
+end

test/footnotes.html.erb

@@ -1,21 +1,25 @@
-<% if notes.any? { |note| note['kind'] == 'self' } -%>
+<% self_notes = notes.select { |note| note['kind'] == 'self' } -%>
+<% link_notes = notes.select { |note| note['kind'] == 'link' } -%>
+<%# -%>
+<% unless self_notes.empty? -%>
 
 <h2>Self references</h2>
 
 <ol>
-<% notes.select { |note| note['kind'] == 'self' }.each do |note| -%>
+<% self_notes.each do |note| -%>
   <li id="<%= note['anchor'] %>" value="<%= note['index'] %>">
     <a href="<%= note['id'] %>.html"><%= note['text'] %></a>
   </li>
 <% end -%>
 </ol>
 <% end -%>
-<% if notes.any? { |note| note['kind'] == 'link' } -%>
+<%# -%>
+<% unless link_notes.empty? -%>
 
 <h2>Link references</h2>
 
 <ol>
-<% notes.select { |note| note['kind'] == 'link' }.each do |note| -%>
+<% link_notes.each do |note| -%>
   <li id="<%= note['anchor'] %>" value="<%= note['index'] %>">
     <a href="<%= note['url'] %>"><%= note['text'] %></a>
   </li>

test/footnotes.json.erb

@@ -0,0 +1,33 @@
+<% self_notes = notes.select { |note| note['kind'] == 'self' } -%>
+<% link_notes = notes.select { |note| note['kind'] == 'link' } -%>
+<%# -%>
+{
+  "self": [
+  <%- self_notes.each_with_index do |note, index| -%>
+    {
+      "index": <%= Integer(note['index']).to_json %>,
+      "kind": "self",
+      "id": <%= String(note['id']).to_json %>,
+      "slug": <%= String(note['slug']).to_json %>,
+      "anchor": <%= String(note['anchor']).to_json %>,
+      "fragment": <%= String(note['fragment']).to_json %>,
+      "url": <%= "#{note['id']}.html".to_json %>,
+      "text": <%= String(note['text']).to_json %>
+    }<%= ',' unless index == self_notes.count - 1 %>
+  <%- end -%>
+  ],
+  "link": [
+  <%- link_notes.each_with_index do |note, index| -%>
+    {
+      "index": <%= Integer(note['index']).to_json %>,
+      "kind": "link",
+      "id": <%= String(note['id']).to_json %>,
+      "slug": <%= String(note['slug']).to_json %>,
+      "anchor": <%= String(note['anchor']).to_json %>,
+      "fragment": <%= String(note['fragment']).to_json %>,
+      "url": <%= String(note['url']).to_json %>,
+      "text": <%= String(note['text']).to_json %>
+    }<%= ',' unless index == link_notes.count - 1 %>
+  <%- end -%>
+  ]
+}