From d3810406f78f73c7cb55e105a5938e3acf2ba246 Mon Sep 17 00:00:00 2001
From: Yusuke Nakamura <yusuke1994525@gmail.com>
Date: Mon, 6 Feb 2023 19:43:39 +0900
Subject: [PATCH 1/6] Add #namespace and #fully_qualified_namespaces to
 RDoc::ClassModule

---
 lib/rdoc/class_module.rb            | 19 +++++++++++++++++++
 test/rdoc/test_rdoc_class_module.rb | 21 +++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/lib/rdoc/class_module.rb b/lib/rdoc/class_module.rb
index c69e14b5e4..b0c2fe86a1 100644
--- a/lib/rdoc/class_module.rb
+++ b/lib/rdoc/class_module.rb
@@ -294,6 +294,25 @@ def full_name
                    end
   end
 
+  ##
+  # Return array of full_name splitted by +::+.
+
+  def namespaces
+    @namespaces ||= full_name.split("::").reject(&:empty?)
+  end
+
+  ##
+  # Return array of fully qualified namespaces.
+  #
+  # For example, if full_name is +A::B::C+, this method returns <code>["A", "A::B", "A::B::C"]</code>
+
+  def fully_qualified_namespaces
+    return namespaces if namespaces.length < 2
+    @fqns ||= namespaces.map.with_index do |_, i|
+      namespaces[0..i].join("::")
+    end
+  end
+
   ##
   # TODO: filter included items by #display?
 
diff --git a/test/rdoc/test_rdoc_class_module.rb b/test/rdoc/test_rdoc_class_module.rb
index 27d37cb7dd..7a94a4f7ee 100644
--- a/test/rdoc/test_rdoc_class_module.rb
+++ b/test/rdoc/test_rdoc_class_module.rb
@@ -1500,4 +1500,25 @@ def test_update_extends_with_colons
     assert_equal [a, c], @c1.extends
   end
 
+  def test_namespaces
+    cm1 = RDoc::ClassModule.new "A"
+    assert_equal ["A"], cm1.namespaces
+
+    cm2 = RDoc::ClassModule.new "A::B"
+    assert_equal ["A", "B"], cm2.namespaces
+
+    cm3 = RDoc::ClassModule.new "::A::B::C"
+    assert_equal ["A", "B", "C"], cm3.namespaces
+  end
+
+  def test_fully_qualified_namespaces
+    cm1 = RDoc::ClassModule.new "A"
+    assert_equal ["A"], cm1.fully_qualified_namespaces
+
+    cm2 = RDoc::ClassModule.new "A::B"
+    assert_equal ["A", "A::B"], cm2.fully_qualified_namespaces
+
+    cm3 = RDoc::ClassModule.new "::A::B::C"
+    assert_equal ["A", "A::B", "A::B::C"], cm3.fully_qualified_namespaces
+  end
 end

From 3ad477d725aeb59d3c8ed44a71df66470ad2fcc8 Mon Sep 17 00:00:00 2001
From: Yusuke Nakamura <yusuke1994525@gmail.com>
Date: Mon, 6 Feb 2023 19:44:59 +0900
Subject: [PATCH 2/6] Create medhods to build metadata to create breadcrumb

---
 lib/rdoc/generator/darkfish.rb | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/lib/rdoc/generator/darkfish.rb b/lib/rdoc/generator/darkfish.rb
index 1b408a6f8e..f5e1203fd9 100644
--- a/lib/rdoc/generator/darkfish.rb
+++ b/lib/rdoc/generator/darkfish.rb
@@ -350,6 +350,8 @@ def generate_class klass, template_file = nil
     asset_rel_prefix = rel_prefix + @asset_rel_path
     svninfo          = get_svninfo(current)
 
+    breadcrumb = generate_namespaces_breadcrumb(current, rel_prefix)
+
     @title = "#{klass.type} #{klass.full_name} - #{@options.title}"
 
     debug_msg "  rendering #{out_file}"
@@ -783,4 +785,21 @@ def template_for file, page = true, klass = ERB
     template
   end
 
+  private
+
+  def namespaces_to_class_modules klass
+    tree = {}
+
+    klass.namespaces.zip(klass.fully_qualified_namespaces) do |ns, fqns|
+      tree[ns] = @store.classes_hash[fqns] || @store.modules_hash[fqns]
+    end
+
+    tree
+  end
+
+  def generate_namespaces_breadcrumb klass, rel_prefix
+    namespaces_to_class_modules(klass).map do |namespace, class_module|
+      { name: namespace, path: (rel_prefix + class_module.path).to_s, self: klass.full_name == class_module.full_name }
+    end
+  end
 end

From 19154aa06c195d8205559cdd8de13bb168e51fdb Mon Sep 17 00:00:00 2001
From: Yusuke Nakamura <yusuke1994525@gmail.com>
Date: Mon, 6 Feb 2023 19:46:20 +0900
Subject: [PATCH 3/6] Show breadcrumb on top of a class document

---
 .../generator/template/darkfish/class.rhtml   | 14 ++++++++++++
 .../generator/template/darkfish/css/rdoc.css  | 22 +++++++++++++++++++
 2 files changed, 36 insertions(+)

diff --git a/lib/rdoc/generator/template/darkfish/class.rhtml b/lib/rdoc/generator/template/darkfish/class.rhtml
index d6510336df..a009a29c25 100644
--- a/lib/rdoc/generator/template/darkfish/class.rhtml
+++ b/lib/rdoc/generator/template/darkfish/class.rhtml
@@ -16,6 +16,20 @@
   </div>
 </nav>
 
+<nav role="navigation" aria-label="breadcrumb" class="breadcrumb">
+  <ol>
+    <% breadcrumb.each do |namespace| %>
+    <li>
+      <% if namespace[:self] %>
+      <span><%= namespace[:name] %></span>
+      <% else %>
+      <a href="<%= namespace[:path] %>"><%= namespace[:name] %></a><span>::</span>
+      <% end %>
+    </li>
+    <% end %>
+  </ol>
+</nav>
+
 <main role="main" aria-labelledby="<%=h klass.aref %>">
   <h1 id="<%=h klass.aref %>" class="<%= klass.type %>">
     <%= klass.type %> <%= klass.full_name %>
diff --git a/lib/rdoc/generator/template/darkfish/css/rdoc.css b/lib/rdoc/generator/template/darkfish/css/rdoc.css
index 2cc55e03b1..c92cd595d2 100644
--- a/lib/rdoc/generator/template/darkfish/css/rdoc.css
+++ b/lib/rdoc/generator/template/darkfish/css/rdoc.css
@@ -273,6 +273,28 @@ nav h3,
   color: #555;
 }
 
+nav.breadcrumb {
+  display: block;
+  float: unset;
+  width: unset;
+  height: unset;
+  border: none;
+  position: unset;
+  top: unset;
+  padding-top: 10px;
+  padding-left: 20px;
+  margin-bottom: 1em;
+}
+
+nav.breadcrumb ol {
+  display: inline-block;
+}
+
+nav.breadcrumb li {
+  display: inline-block;
+  font-size: 125%;
+}
+
 nav ul,
 nav dl,
 nav p {

From 66291fd8436a322e0cc3ab418abf320305b07561 Mon Sep 17 00:00:00 2001
From: Yusuke Nakamura <yusuke1994525@gmail.com>
Date: Thu, 9 Feb 2023 00:43:59 +0900
Subject: [PATCH 4/6] Add nil guard to generate_namespaces_breadcrumb

---
 lib/rdoc/generator/darkfish.rb | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/rdoc/generator/darkfish.rb b/lib/rdoc/generator/darkfish.rb
index f5e1203fd9..204bfc7cdc 100644
--- a/lib/rdoc/generator/darkfish.rb
+++ b/lib/rdoc/generator/darkfish.rb
@@ -799,7 +799,8 @@ def namespaces_to_class_modules klass
 
   def generate_namespaces_breadcrumb klass, rel_prefix
     namespaces_to_class_modules(klass).map do |namespace, class_module|
-      { name: namespace, path: (rel_prefix + class_module.path).to_s, self: klass.full_name == class_module.full_name }
+      path = class_module ? (rel_prefix + class_module.path).to_s : ""
+      { name: namespace, path: path, self: klass.full_name == class_module&.full_name }
     end
   end
 end

From 168ea674db279cd8547c10af72ae827a6306b727 Mon Sep 17 00:00:00 2001
From: Yusuke Nakamura <yusuke1994525@gmail.com>
Date: Thu, 6 Jul 2023 18:00:12 +0900
Subject: [PATCH 5/6] Rename to nesting_namespaces

---
 lib/rdoc/class_module.rb            | 12 ++++++------
 test/rdoc/test_rdoc_class_module.rb | 16 ++++++++--------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/lib/rdoc/class_module.rb b/lib/rdoc/class_module.rb
index b0c2fe86a1..85710fadbc 100644
--- a/lib/rdoc/class_module.rb
+++ b/lib/rdoc/class_module.rb
@@ -297,19 +297,19 @@ def full_name
   ##
   # Return array of full_name splitted by +::+.
 
-  def namespaces
+  def nesting_namespaces
     @namespaces ||= full_name.split("::").reject(&:empty?)
   end
 
   ##
-  # Return array of fully qualified namespaces.
+  # Return array of fully qualified nesting namespaces.
   #
   # For example, if full_name is +A::B::C+, this method returns <code>["A", "A::B", "A::B::C"]</code>
 
-  def fully_qualified_namespaces
-    return namespaces if namespaces.length < 2
-    @fqns ||= namespaces.map.with_index do |_, i|
-      namespaces[0..i].join("::")
+  def fully_qualified_nesting_namespaces
+    return nesting_namespaces if nesting_namespaces.length < 2
+    @fqns ||= nesting_namespaces.map.with_index do |_, i|
+      nesting_namespaces[0..i].join("::")
     end
   end
 
diff --git a/test/rdoc/test_rdoc_class_module.rb b/test/rdoc/test_rdoc_class_module.rb
index 7a94a4f7ee..f0a3859133 100644
--- a/test/rdoc/test_rdoc_class_module.rb
+++ b/test/rdoc/test_rdoc_class_module.rb
@@ -1500,25 +1500,25 @@ def test_update_extends_with_colons
     assert_equal [a, c], @c1.extends
   end
 
-  def test_namespaces
+  def test_nesting_namespaces
     cm1 = RDoc::ClassModule.new "A"
-    assert_equal ["A"], cm1.namespaces
+    assert_equal ["A"], cm1.nesting_namespaces
 
     cm2 = RDoc::ClassModule.new "A::B"
-    assert_equal ["A", "B"], cm2.namespaces
+    assert_equal ["A", "B"], cm2.nesting_namespaces
 
     cm3 = RDoc::ClassModule.new "::A::B::C"
-    assert_equal ["A", "B", "C"], cm3.namespaces
+    assert_equal ["A", "B", "C"], cm3.nesting_namespaces
   end
 
-  def test_fully_qualified_namespaces
+  def test_fully_qualified_nesting_namespaces
     cm1 = RDoc::ClassModule.new "A"
-    assert_equal ["A"], cm1.fully_qualified_namespaces
+    assert_equal ["A"], cm1.fully_qualified_nesting_namespaces
 
     cm2 = RDoc::ClassModule.new "A::B"
-    assert_equal ["A", "A::B"], cm2.fully_qualified_namespaces
+    assert_equal ["A", "A::B"], cm2.fully_qualified_nesting_namespaces
 
     cm3 = RDoc::ClassModule.new "::A::B::C"
-    assert_equal ["A", "A::B", "A::B::C"], cm3.fully_qualified_namespaces
+    assert_equal ["A", "A::B", "A::B::C"], cm3.fully_qualified_nesting_namespaces
   end
 end

From ec0072b163455b79b6a4eb778c31e14ff07ffd22 Mon Sep 17 00:00:00 2001
From: Yusuke Nakamura <yusuke1994525@gmail.com>
Date: Thu, 6 Jul 2023 18:01:21 +0900
Subject: [PATCH 6/6] Refactor fully_qualified_nesting_namespaces

---
 lib/rdoc/class_module.rb | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/rdoc/class_module.rb b/lib/rdoc/class_module.rb
index 85710fadbc..7a0bec72d8 100644
--- a/lib/rdoc/class_module.rb
+++ b/lib/rdoc/class_module.rb
@@ -308,8 +308,8 @@ def nesting_namespaces
 
   def fully_qualified_nesting_namespaces
     return nesting_namespaces if nesting_namespaces.length < 2
-    @fqns ||= nesting_namespaces.map.with_index do |_, i|
-      nesting_namespaces[0..i].join("::")
+    @fqns ||= nesting_namespaces.inject([]) do |list, n|
+      list << (list.empty? ? n : "#{list.last}::#{n}")
     end
   end