Fix resolution of reference tags in a referenced docstring

lib/yard/docstring.rb

@@ -46,6 +46,9 @@ def parser(*args) default_parser.new(*args) end
     # @return [CodeObjects::Base] the object that owns the docstring.
     attr_accessor :object
 
+    # @return [CodeObjects::Base] the namespace of the docstring
+    attr_reader :namespace
+
     # @return [Range] line range in the {#object}'s file where the docstring was parsed from
     attr_accessor :line_range
 
@@ -79,6 +82,7 @@ def self.new!(text, tags = [], object = nil, raw_data = nil, ref_object = nil)
       docstring.replace(text, false)
       docstring.object = object
       docstring.add_tag(*tags)
+      docstring.instance_variable_set("@namespace", object)
       docstring.instance_variable_set("@unresolved_reference", ref_object)
       docstring.instance_variable_set("@all", raw_data) if raw_data
       docstring
@@ -102,6 +106,7 @@ def self.new!(text, tags = [], object = nil, raw_data = nil, ref_object = nil)
     #   with.
     def initialize(content = '', object = nil)
       @object = object
+      @namespace = object
       @summary = nil
       @hash_flag = false
 
@@ -330,9 +335,9 @@ def resolve_reference
         return if defined?(@unresolved_reference).nil? || @unresolved_reference.nil?
         return if CodeObjects::Proxy === @unresolved_reference
 
-        reference = @unresolved_reference
+        @namespace = @unresolved_reference
         @unresolved_reference = nil
-        self.all = [reference.docstring.all, @all].join("\n")
+        self.all = [@namespace.docstring.all, @all].join("\n")
       end
     end
 

lib/yard/docstring_parser.rb

@@ -224,7 +224,8 @@ def create_tag(tag_name, tag_buf = '')
 
     # Creates a {Tags::RefTag}
     def create_ref_tag(tag_name, name, object_name)
-      @tags << Tags::RefTagList.new(tag_name, P(object, object_name), name)
+      namespace = object && object.docstring ? object.docstring.namespace : object
+      @tags << Tags::RefTagList.new(tag_name, P(namespace, object_name), name)
     end
 
     # Creates a new directive using the registered {#library}

spec/docstring_spec.rb

@@ -182,6 +182,25 @@
       expect(tags.first.owner).to eq o
     end
 
+    it "uses the right namespace following ref tags through a docstring reference" do
+      YARD.parse_string <<-eof
+        class A
+          class B
+            # @param x
+            def b(x); end
+          end
+          # @param x (see B#b)
+          def a(x);end
+        end
+        class C
+          # (see A#a)
+          def c(x);end
+        end
+      eof
+
+      expect(YARD::Registry.at('C#c').tags.map(&:name)).to eq ['x']
+    end
+
     it "returns an empty list (and warning) if circular reftags are found" do
       YARD.parse_string <<-eof
         class Foo