Index singleton methods with class << self

lib/ruby_indexer/lib/ruby_indexer/visitor.rb

@@ -10,6 +10,7 @@ def initialize(index, parse_result, file_path)
       @index = index
       @file_path = file_path
       @stack = T.let([], T::Array[String])
+      @singleton = T.let(false, T::Boolean)
       @comments_by_line = T.let(
         parse_result.comments.to_h do |c|
           [c.location.start_line, c]
@@ -25,6 +26,13 @@ def visit_class_node(node)
       add_class_entry(node)
     end
 
+    sig { override.params(node: Prism::SingletonClassNode).void }
+    def visit_singleton_class_node(node)
+      @singleton = true
+      super
+      @singleton = false
+    end
+
     sig { override.params(node: Prism::ModuleNode).void }
     def visit_module_node(node)
       add_module_entry(node)
@@ -126,7 +134,11 @@ def visit_def_node(node)
       comments = collect_comments(node)
       case node.receiver
       when nil
-        @index << Entry::InstanceMethod.new(method_name, @file_path, node.location, comments, node.parameters)
+        @index << if @singleton
+          Entry::SingletonMethod.new(method_name, @file_path, node.location, comments, node.parameters)
+        else
+          Entry::InstanceMethod.new(method_name, @file_path, node.location, comments, node.parameters)
+        end
       when Prism::SelfNode
         @index << Entry::SingletonMethod.new(method_name, @file_path, node.location, comments, node.parameters)
       end

lib/ruby_indexer/test/method_test.rb

@@ -16,7 +16,39 @@ def bar
       assert_entry("bar", Entry::InstanceMethod, "/fake/path/foo.rb:1-2:2-5")
     end
 
-    def test_singleton_method_using_self_receiver
+    def test_singleton_method_using_class_self
+      index(<<~RUBY)
+        class Foo
+          class << self
+            def bar
+            end
+          end
+
+          def baz
+          end
+        end
+      RUBY
+
+      assert_entry("bar", Entry::SingletonMethod, "/fake/path/foo.rb:2-4:3-7")
+      assert_entry("baz", Entry::InstanceMethod, "/fake/path/foo.rb:6-2:7-5")
+    end
+
+    def test_singleton_method_using_class_self_with_nesting
+      index(<<~RUBY)
+        class Foo
+          class << self
+            class Nested
+              def bar
+              end
+            end
+          end
+        end
+      RUBY
+
+      assert_entry("bar", Entry::SingletonMethod, "/fake/path/foo.rb:3-6:4-9")
+    end
+
+    def test_singleton_method_using_class
       index(<<~RUBY)
         class Foo
           def self.bar