nixos-render-docs: wrap code in <pre><code>, not <pre>

newer hljs stylesheets work best with <pre><code> wrapping, and it's
semantically more accurate as well.

pkgs/tools/nix/nixos-render-docs/src/nixos_render_docs/html.py

@@ -98,7 +98,7 @@ class HTMLRenderer(Renderer):
         return "</strong></span>"
     def fence(self, token: Token, tokens: Sequence[Token], i: int) -> str:
         info = f" {escape(token.info, True)}" if token.info != "" else ""
-        return f'<pre class="programlisting{info}">\n{escape(token.content)}</pre>'
+        return f'<pre><code class="programlisting{info}">{escape(token.content)}</code></pre>'
     def blockquote_open(self, token: Token, tokens: Sequence[Token], i: int) -> str:
         return '<div class="blockquote"><blockquote class="blockquote">'
     def blockquote_close(self, token: Token, tokens: Sequence[Token], i: int) -> str:

pkgs/tools/nix/nixos-render-docs/src/nixos_render_docs/options.py

@@ -497,7 +497,7 @@ class OptionsHTMLRenderer(OptionDocsRestrictions, HTMLRenderer):
         return super().bullet_list_open(token, tokens, i)
     def fence(self, token: Token, tokens: Sequence[Token], i: int) -> str:
         info = f" {html.escape(token.info, True)}" if token.info != "" else ""
-        return f'<pre class="programlisting{info}">{html.escape(token.content)}</pre>'
+        return f'<pre><code class="programlisting{info}">{html.escape(token.content)}</code></pre>'
 
 class HTMLConverter(BaseConverter[OptionsHTMLRenderer]):
     __option_block_separator__ = ""

pkgs/tools/nix/nixos-render-docs/src/tests/test_html.py

@@ -204,8 +204,10 @@ def test_full() -> None:
           <div class="blockquote">
            <blockquote class="blockquote">
             <p>with <span class="emphasis"><em>nesting</em></span></p>
-            <pre class="programlisting">↵
-             nested code block↵
+            <pre>
+             <code class="programlisting">
+              nested code block↵
+             </code>
             </pre>
            </blockquote>
           </div>
@@ -213,8 +215,10 @@ def test_full() -> None:
            <ul class="itemizedlist compact" style="list-style-type: disc;">
             <li class="listitem"><p>and lists</p></li>
             <li class="listitem">
-             <pre class="programlisting">↵
-              containing code↵
+             <pre>
+              <code class="programlisting">
+               containing code↵
+              </code>
              </pre>
             </li>
            </ul>
@@ -240,11 +244,15 @@ def test_full() -> None:
              </p>
             </blockquote>
            </div>
-           <pre class="programlisting">↵
-            code block↵
+           <pre>
+            <code class="programlisting">
+             code block↵
+            </code>
            </pre>
-           <pre class="programlisting">↵
-            fenced block↵
+           <pre>
+            <code class="programlisting">
+             fenced block↵
+            </code>
            </pre>
            <p>text</p>
           </dd>