[gi-docgen/hierarchy-links] Add links to external classes in the hierarchy

[Emmanuele Bassi <ebassi src gnome org>]

commit 504a62e5fe9eb4bfbbf9824e0f2d1ce04422472a
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Fri Jul 29 14:29:55 2022 +0100

    Add links to external classes in the hierarchy
    
    We have their namespace and type name, which means we can construct the
    external links and let the URL map do its job.
    
    Fixes: #132

 gidocgen/gdgenerate.py | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)
---
diff --git a/gidocgen/gdgenerate.py b/gidocgen/gdgenerate.py
index 42ed782..6323931 100644
--- a/gidocgen/gdgenerate.py
+++ b/gidocgen/gdgenerate.py
@@ -2675,7 +2675,12 @@ def gen_types_hierarchy(config, theme_config, output_dir, jinja_env, repository)
     def dump_tree(node, out):
         for k in node:
             if '.' in k:
-                out.append(f'<li class="type"><code>{k}</code>')
+                ns, name = k.split('.', 2)
+                data_ns = f'data-namespace="{ns}"'
+                data_link = f'data-link="class.{name}.html"'
+                href = 'href="javascript:void(0)"'
+                css_class = 'class="external"'
+                out.append(f'<li class="type"><a {data_ns} {data_link} {href} 
{css_class}><code>{k}</code></a>')
             else:
                 out.append(f'<li class="type"><a href="class.{k}.html"><code>{k}</code></a>')
             if len(node[k]) != 0:
@@ -2687,7 +2692,7 @@ def gen_types_hierarchy(config, theme_config, output_dir, jinja_env, repository)
     if len(objects_tree) != 0:
         res += ["<div class=\"docblock\">"]
         res += ["<ul class=\"type root\">"]
-        res += [" <li class=\"type\"><code>GObject</code></li><ul class=\"type\">"]
+        res += [" <li class=\"type\"><a data-namespace=\"GObject\" data-link=\"class.Object.html\" 
href=\"javascript:void(0)\" class=\"external\"><code>GObject.Object</code></a></li><ul class=\"type\">"]  # 
noqa: E501
         dump_tree(objects_tree, res)
         res += [" </ul></li>"]
         res += ["</ul>"]
@@ -2696,7 +2701,7 @@ def gen_types_hierarchy(config, theme_config, output_dir, jinja_env, repository)
     if len(typed_tree) != 0:
         res += ["<div class=\"docblock\">"]
         res += ["<ul class=\"type root\">"]
-        res += [" <li class=\"type\"><code>GTypeInstance</code></li><ul class=\"type\">"]
+        res += [" <li class=\"type\"><a data-namespace=\"GObject\" data-link=\"struct.TypeInstance.html\" 
href=\"javascript:void(0)\" class=\"external\"><code>GObject.TypeInstance</code></li><ul class=\"type\">"]  # 
noqa: E501
         dump_tree(typed_tree, res)
         res += [" </ul></li>"]
         res += ["</ul>"]