Restore Ruby 2.6 compatibility

CHANGELOG.md

@@ -10,7 +10,9 @@
 
 ##### Bug Fixes
 
-* None.
+* Restore compatibility with Ruby 2.6  
+  [John Fairhurst](https://github.com/johnfairh)
+  [#1388](https://github.com/realm/jazzy/issues/1388)
 
 ## 0.15.0
 

lib/jazzy/config.rb

@@ -717,12 +717,12 @@ def parse_module_configs
 
       if modules.first.is_a?(String)
         # Massage format (2) into (3)
-        self.modules = modules.map { { 'module' => _1 } }
+        self.modules = modules.map { |mod| { 'module' => mod } }
       end
 
       # Allow per-module overrides of only some config options
       attrs_by_conf_key, attrs_by_name =
-        grouped_attributes { _1.select(&:per_module) }
+        grouped_attributes { |attr| attr.select(&:per_module) }
 
       modules.map do |module_hash|
         mod_name = module_hash['module'] || ''

lib/jazzy/grouper.rb

@@ -24,7 +24,7 @@ def self.group_docs(docs, doc_index)
     # Group root-level docs by type
     def self.group_docs_by_type(docs, type_category_prefix)
       type_groups = SourceDeclaration::Type.all.map do |type|
-        children, docs = docs.partition { _1.type == type }
+        children, docs = docs.partition { |doc| doc.type == type }
         make_type_group(children, type, type_category_prefix)
       end
       merge_categories(type_groups.compact) + docs
@@ -49,7 +49,7 @@ def self.group_docs_by_module(docs, type_category_prefix)
 
     def self.group_custom_categories(docs, doc_index)
       group = config.custom_categories.map do |category|
-        children = category['children'].filter_map do |name|
+        children = category['children'].map do |name|
           unless doc = doc_index.lookup(name)
             warn 'WARNING: No documented top-level declarations match ' \
               "name \"#{name}\" specified in categories file"
@@ -64,7 +64,7 @@ def self.group_custom_categories(docs, doc_index)
           end
 
           docs.delete(doc)
-        end
+        end.compact
         # Category config overrides alphabetization
         children.each.with_index { |child, i| child.nav_order = i }
         make_group(children, category['name'], '')
@@ -73,7 +73,7 @@ def self.group_custom_categories(docs, doc_index)
     end
 
     def self.group_guides(docs, prefix)
-      guides, others = docs.partition { _1.type.markdown? }
+      guides, others = docs.partition { |doc| doc.type.markdown? }
       return [[], others] unless guides.any?
 
       [[make_type_group(guides, guides.first.type, prefix)], others]
@@ -92,7 +92,7 @@ def self.make_type_group(docs, type, type_category_prefix)
     def self.merge_categories(categories)
       merged = []
       categories.each do |new_category|
-        if existing = merged.find { _1.name == new_category.name }
+        if existing = merged.find { |cat| cat.name == new_category.name }
           existing.children += new_category.children
         else
           merged.append(new_category)
@@ -102,7 +102,7 @@ def self.merge_categories(categories)
     end
 
     def self.make_group(group, name, abstract, url_name = nil)
-      group.reject! { _1.name.empty? }
+      group.reject! { |decl| decl.name.empty? }
       unless group.empty?
         SourceDeclaration.new.tap do |sd|
           sd.type     = SourceDeclaration::Type.overview

lib/jazzy/sourcekitten.rb

@@ -692,7 +692,7 @@ def self.mergeable_objc?(decl, root_decls)
       decl.type.objc_class? ||
         (decl.type.objc_category? &&
           (category_classname = decl.objc_category_name[0]) &&
-          root_decls.any? { _1.name == category_classname })
+          root_decls.any? { |d| d.name == category_classname })
     end
 
     # Returns if a Swift declaration is mergeable.
@@ -919,7 +919,9 @@ def self.merge_code_declaration(decls)
 
     # Grab all the extensions from the same doc module
     def self.next_doc_module_group(decls)
-      decls.partition { _1.doc_module_name == decls.first.doc_module_name }
+      decls.partition do |decl|
+        decl.doc_module_name == decls.first.doc_module_name
+      end
     end
 
     # Does this extension/type need a note explaining which doc module it is from?
@@ -1055,12 +1057,12 @@ def self.reject_objc_types(docs)
     # Remove top-level enum cases because it means they have an ACL lower
     # than min_acl
     def self.reject_swift_types(docs)
-      docs.reject { _1.type.swift_enum_element? }
+      docs.reject { |doc| doc.type.swift_enum_element? }
     end
 
     # Spot and mark any categories on classes not declared in these docs
     def self.mark_objc_external_categories(docs)
-      class_names = docs.select { _1.type.objc_class? }.to_set(&:name)
+      class_names = docs.select { |doc| doc.type.objc_class? }.to_set(&:name)
 
       docs.map do |doc|
         if (names = doc.objc_category_name) && !class_names.include?(names.first)