[WIP] Allow nested categories with recursive navigation.

lib/jazzy/config.rb

@@ -310,7 +310,13 @@ def expand_path(path)
       description: ['Custom navigation categories to replace the standard '\
                     '“Classes, Protocols, etc.”', 'Types not explicitly named '\
                     'in a custom category appear in generic groups at the end.',
-                    'Example: https://git.io/v4Bcp'],
+                    'You can add another category in the children array '\
+                    'instead of using a type name, to create ',
+                    'subcategories. This can be repeated ad infinitum, '\
+                    'provided your theme supports it.',
+                    'Currently all integrated themes support a maximum ',
+                    'of 3 levels.',
+                    'Example: https://git.io/fNvGB'],
       default: []
 
     config_attr :custom_head,

lib/jazzy/doc_builder.rb

@@ -34,22 +34,36 @@ def self.doc_structure_for_docs(docs)
         children = doc.children
                       .sort_by { |c| [c.nav_order, c.name, c.usr || ''] }
                       .flat_map do |child|
-          # FIXME: include arbitrarily nested extensible types
-          [{ name: child.name, url: child.url }] +
-            Array(child.children.select do |sub_child|
-              sub_child.type.swift_extensible? || sub_child.type.extension?
-            end).map do |sub_child|
-              { name: "– #{sub_child.name}", url: sub_child.url }
-            end
+          if child.type.overview?
+            doc_structure_for_docs([child])
+          else
+            doc_structure_for_child(child)
+          end
         end
+
         {
           section: doc.name,
           url: doc.url,
           children: children,
+          level: doc.level,
         }
       end
     end
 
+    # Generate structure for children of a category in sidebar navigation.
+    # @return [Array] doc structure compromised of
+    #                     name and url of the child as well as
+    #                     any possible nested children.
+    def self.doc_structure_for_child(child)
+      # FIXME: include arbitrarily nested extensible types
+      [{ name: child.name, url: child.url, children: nil }] +
+        Array(child.children.select do |sub_child|
+          sub_child.type.swift_extensible? || sub_child.type.extension?
+        end).map do |sub_child|
+          { name: "– #{sub_child.name}", url: sub_child.url, children: nil }
+        end
+    end
+
     # Build documentation from the given options
     # @param [Config] options
     # @return [SourceModule] the documented source module
@@ -383,6 +397,34 @@ def self.render_tasks(source_module, children)
       end
     end
 
+    def self.render_subsections(subsections, source_module)
+      subsections.map do |subsection|
+        overview = render_overview(subsection)
+        tasks = render_tasks(
+          source_module,
+          subsection.children.reject { |c| c.type.overview? },
+        )
+
+        {
+          name: subsection.name,
+          overview: overview,
+          uid: URI.encode(subsection.name),
+          url: subsection.url,
+          level: subsection.level,
+          tasks: tasks,
+        }
+      end
+    end
+
+    def self.render_overview(doc)
+      overview = (doc.abstract || '') + (doc.discussion || '')
+      alternative_abstract = doc.alternative_abstract
+      if alternative_abstract
+        overview = render(doc, alternative_abstract) + overview
+      end
+      overview
+    end
+
     # rubocop:disable Metrics/MethodLength
     # Build Mustache document from single parsed doc
     # @param [Config] options Build options
@@ -395,11 +437,7 @@ def self.document(source_module, doc_model, path_to_root)
         return document_markdown(source_module, doc_model, path_to_root)
       end
 
-      overview = (doc_model.abstract || '') + (doc_model.discussion || '')
-      alternative_abstract = doc_model.alternative_abstract
-      if alternative_abstract
-        overview = render(doc_model, alternative_abstract) + overview
-      end
+      overview = render_overview(doc_model)
 
       doc = Doc.new # Mustache model instance
       doc[:custom_head] = Config.instance.custom_head
@@ -412,7 +450,10 @@ def self.document(source_module, doc_model, path_to_root)
       doc[:declaration] = doc_model.display_declaration
       doc[:overview] = overview
       doc[:structure] = source_module.doc_structure
-      doc[:tasks] = render_tasks(source_module, doc_model.children)
+      categories, children =
+        doc_model.children.partition { |c| c.type.overview? }
+      doc[:tasks] = render_tasks(source_module, children)
+      doc[:subsections] = render_subsections(categories, source_module)
       doc[:module_name] = source_module.name
       doc[:author_name] = source_module.author_name
       doc[:github_url] = source_module.github_url

lib/jazzy/source_category.rb

@@ -0,0 +1,77 @@
+require 'jazzy/source_declaration'
+require 'jazzy/config'
+require 'jazzy/source_mark'
+require 'jazzy/jazzy_markdown'
+
+module Jazzy
+  # Category (group, contents) pages generated by jazzy
+  class SourceCategory < SourceDeclaration
+    extend Config::Mixin
+
+    def initialize(group, name, abstract, url_name, level = 1)
+      super()
+      self.type     = SourceDeclaration::Type.overview
+      self.name     = name
+      self.url_name = url_name
+      self.abstract = Markdown.render(abstract)
+      self.children = group
+      self.parameters = []
+      self.level      = level
+    end
+
+    # Group root-level docs into custom categories or by type
+    def self.group_docs(docs)
+      custom_categories, docs =
+        group_custom_categories(docs, config.custom_categories)
+      type_categories, uncategorized = group_type_categories(
+        docs, custom_categories.any? ? 'Other ' : ''
+      )
+      custom_categories + type_categories + uncategorized
+    end
+
+    def self.group_custom_categories(docs, categories, level = 1)
+      group = categories.map do |category|
+        children = category['children'].flat_map do |child|
+          if child.is_a?(Hash)
+            # Nested category, recurse
+            children, docs = group_custom_categories(docs, [child], level + 1)
+          else
+            # Doc name, find it
+            children, docs = docs.partition { |doc| doc.name == child }
+            if children.empty?
+              STDERR.puts(
+                'WARNING: No documented top-level declarations match ' \
+                "name \"#{child}\" specified in categories file",
+              )
+            end
+          end
+          children
+        end
+        # Category config overrides alphabetization
+        children.each.with_index { |child, i| child.nav_order = i }
+        make_group(children, category['name'], '', nil, level)
+      end
+      [group.compact, docs]
+    end
+
+    def self.group_type_categories(docs, type_category_prefix)
+      group = SourceDeclaration::Type.all.map do |type|
+        children, docs = docs.partition { |doc| doc.type == type }
+        make_group(
+          children,
+          type_category_prefix + type.plural_name,
+          "The following #{type.plural_name.downcase} are available globally.",
+          type_category_prefix + type.plural_url_name,
+        )
+      end
+      [group.compact, docs]
+    end
+
+    def self.make_group(group, name, abstract, url_name = nil, level = 1)
+      group.reject! { |doc| doc.name.empty? }
+      unless group.empty?
+        SourceCategory.new(group, name, abstract, url_name, level)
+      end
+    end
+  end
+end

lib/jazzy/source_declaration.rb

@@ -45,6 +45,19 @@ def namespace_ancestors
       end
     end
 
+    # Chain of parent_in_docs from top level to self. (Includes self.)
+    def documentation_path
+      documentation_ancestors + [self]
+    end
+
+    def documentation_ancestors
+      if parent_in_docs
+        parent_in_docs.documentation_path
+      else
+        []
+      end
+    end
+
     def fully_qualified_name
       namespace_path.map(&:name).join('.')
     end
@@ -99,6 +112,7 @@ def display_other_language_declaration
     attr_accessor :end_line
     attr_accessor :nav_order
     attr_accessor :url_name
+    attr_accessor :level
 
     def alternative_abstract
       if file = alternative_abstract_file

lib/jazzy/source_declaration/type.rb

@@ -125,6 +125,10 @@ def objc_unexposed?
         kind == 'sourcekitten.source.lang.objc.decl.unexposed'
       end
 
+      def overview?
+        Type.overview == self
+      end
+
       def self.overview
         Type.new('Overview')
       end

lib/jazzy/sourcekitten.rb

@@ -11,6 +11,7 @@
 require 'jazzy/source_declaration'
 require 'jazzy/source_mark'
 require 'jazzy/stats'
+require 'jazzy/source_category'
 
 ELIDED_AUTOLINK_TOKEN = '36f8f5912051ae747ef441d6511ca4cb'.freeze
 
@@ -59,58 +60,6 @@ def self.undocumented_abstract
       ).freeze
     end
 
-    # Group root-level docs by custom categories (if any) and type
-    def self.group_docs(docs)
-      custom_categories, docs = group_custom_categories(docs)
-      type_categories, uncategorized = group_type_categories(
-        docs, custom_categories.any? ? 'Other ' : ''
-      )
-      custom_categories + type_categories + uncategorized
-    end
-
-    def self.group_custom_categories(docs)
-      group = Config.instance.custom_categories.map do |category|
-        children = category['children'].flat_map do |name|
-          docs_with_name, docs = docs.partition { |doc| doc.name == name }
-          if docs_with_name.empty?
-            STDERR.puts 'WARNING: No documented top-level declarations match ' \
-                        "name \"#{name}\" specified in categories file"
-          end
-          docs_with_name
-        end
-        # Category config overrides alphabetization
-        children.each.with_index { |child, i| child.nav_order = i }
-        make_group(children, category['name'], '')
-      end
-      [group.compact, docs]
-    end
-
-    def self.group_type_categories(docs, type_category_prefix)
-      group = SourceDeclaration::Type.all.map do |type|
-        children, docs = docs.partition { |doc| doc.type == type }
-        make_group(
-          children,
-          type_category_prefix + type.plural_name,
-          "The following #{type.plural_name.downcase} are available globally.",
-          type_category_prefix + type.plural_url_name,
-        )
-      end
-      [group.compact, docs]
-    end
-
-    def self.make_group(group, name, abstract, url_name = nil)
-      group.reject! { |doc| doc.name.empty? }
-      unless group.empty?
-        SourceDeclaration.new.tap do |sd|
-          sd.type     = SourceDeclaration::Type.overview
-          sd.name     = name
-          sd.url_name = url_name
-          sd.abstract = Markdown.render(abstract)
-          sd.children = group
-        end
-      end
-    end
-
     def self.sanitize_filename(doc)
       unsafe_filename = doc.url_name || doc.name
       sanitzation_enabled = Config.instance.use_safe_filenames
@@ -168,8 +117,12 @@ def self.subdir_for_doc(doc)
         # File program elements under top ancestor’s type (Struct, Class, etc.)
         [top_level_decl.type.plural_url_name] +
           doc.namespace_ancestors.map(&:name)
-      else
+      elsif doc.type == SourceDeclaration::Type.overview
         # Categories live in their own directory
+        # But subcategories live in a directory named after their parent
+        doc.documentation_ancestors.map(&:name)
+      else
+        # Anything else
         []
       end
     end
@@ -806,7 +759,7 @@ def self.parse(sourcekitten_output, min_acl, skip_undocumented, inject_docs)
         docs = docs.reject { |doc| doc.type.swift_enum_element? }
       end
       ungrouped_docs = docs
-      docs = group_docs(docs)
+      docs = SourceCategory.group_docs(docs)
       make_doc_urls(docs)
       autolink(docs, ungrouped_docs)
       [docs, @stats]