From f00c6d6d277513d5bdf4c8f3b24d574666032058 Mon Sep 17 00:00:00 2001
From: Jonathan Hefner <jonathan@hefner.pro>
Date: Mon, 25 Sep 2023 15:59:26 -0500
Subject: [PATCH] Fix breadcrumbs for flattened class declarations

When declaring a class with a flattened name like `class Foo::Bar`
rather than `module Foo; class Bar`, RDoc does not return a parent
object for `Bar`.  Note this only applies to classes.  When `Bar` is
merely a module, RDoc _does_ return a parent object.

That behavior caused `module_breadcrumbs` to return only the class's
name in such cases.  This commit fixes `module_breadcrumbs` to work
around that behavior and always return all breadcrumbs.
---
 lib/sdoc/helpers.rb  | 10 +++++-----
 spec/helpers_spec.rb | 13 +++++++++++++
 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/lib/sdoc/helpers.rb b/lib/sdoc/helpers.rb
index 44b0f797..42c95693 100644
--- a/lib/sdoc/helpers.rb
+++ b/lib/sdoc/helpers.rb
@@ -120,14 +120,14 @@ def more_less_ul(items, limit)
   end
 
   def module_breadcrumbs(rdoc_module)
-    crumbs = [h(rdoc_module.name)]
+    parent_names = rdoc_module.full_name.split("::")[0...-1]
 
-    rdoc_module.each_parent do |parent|
-      break if parent.is_a?(RDoc::TopLevel)
-      crumbs.unshift(link_to(h(parent.name), parent))
+    crumbs = parent_names.each_with_index.map do |name, i|
+      parent = rdoc_module.store.find_module_named(parent_names[0..i].join("::"))
+      parent ? link_to(h(name), parent) : h(name)
     end
 
-    "<code>#{crumbs.join("::<wbr>")}</code>"
+    "<code>#{[*crumbs, h(rdoc_module.name)].join("::<wbr>")}</code>"
   end
 
   def module_ancestors(rdoc_module)
diff --git a/spec/helpers_spec.rb b/spec/helpers_spec.rb
index 0f590880..7539f0f0 100644
--- a/spec/helpers_spec.rb
+++ b/spec/helpers_spec.rb
@@ -547,6 +547,19 @@ module Foo; module Bar; module Qux; end; end; end
       _(@helpers.module_breadcrumbs(qux)).
         must_equal "<code>#{@helpers.link_to "Foo", foo}::<wbr>#{@helpers.link_to "Bar", bar}::<wbr>Qux</code>"
     end
+
+    it "handles flattened class declarations" do
+      top_level = rdoc_top_level_for <<~RUBY
+        class Foo::Bar::Qux; end
+      RUBY
+
+      foo = top_level.find_module_named("Foo")
+      bar = top_level.find_module_named("Foo::Bar")
+      qux = top_level.find_module_named("Foo::Bar::Qux")
+
+      _(@helpers.module_breadcrumbs(qux)).
+        must_equal "<code>#{@helpers.link_to "Foo", foo}::<wbr>#{@helpers.link_to "Bar", bar}::<wbr>Qux</code>"
+    end
   end
 
   describe "#module_ancestors" do