Better identify Swift default implementations (#1423)

Author: johnfairh

CHANGELOG.md

@@ -20,6 +20,10 @@
  [John Fairhurst](https://github.com/johnfairh)
  [#1414](https://github.com/realm/jazzy/issues/1414)
 
+* Better identify default implementations. 
+ [John Fairhurst](https://github.com/johnfairh)
+ [#1420](https://github.com/realm/jazzy/issues/1420)
+
 ## 0.15.3
 
 ##### Breaking

lib/jazzy/source_declaration.rb

@@ -256,6 +256,21 @@ def declaration_note
  notes.join(', ').upcase_first unless notes.empty?
  end
 
+ # For matching where `Self` is equivalent without considering
+ # constraints
+ def simplified_typename
+ typename&.gsub(/<Self .*?>/, '<Self>')
+ end
+
+ # Is the candidate `SourceDeclaration` probably a default
+ # implementation of this declaration?
+ def default_implementation?(candidate)
+ name == candidate.name &&
+ type == candidate.type &&
+ simplified_typename == candidate.simplified_typename &&
+ async == candidate.async
+ end
+
  def readme?
  false
  end

lib/jazzy/sourcekitten.rb

@@ -856,9 +856,7 @@ def self.mark_and_merge_protocol_extensions(protocol, extensions)
  extensions.each do |ext|
  ext.children = ext.children.select do |ext_member|
  proto_member = protocol.children.find do |p|
- p.name == ext_member.name &&
- p.type == ext_member.type &&
- p.async == ext_member.async
+ p.default_implementation?(ext_member)
  end
 
  # Extension-only method, keep.