Check duplication of instance variable declaration

Author: soutaro

lib/rbs/definition_builder.rb

@@ -155,7 +155,7 @@ def define_instance(definition, type_name, subst, define_class_vars:)
             member.names.each do |name|
               ivar_name = :"@#{name}"
               attr_type = member.type || Types::Bases::Any.new(location: nil)
-              
+
               insert_variable(
                 type_name,
                 definition.instance_variables,
@@ -574,6 +574,7 @@ def insert_variable(type_name, variables, name:, type:, source:)
         declared_in: type_name,
         source: source
       )
+
       validate_variable(variables[name])
     end
 
@@ -584,7 +585,15 @@ def validate_variable(var)
       variables = [] #: Array[Definition::Variable]
       tmp_var = var
       while tmp_var
-        variables << tmp_var if tmp_var.source.is_a?(AST::Members::Var)
+        case tmp_var.source
+        when AST::Members::AttrReader, AST::Members::AttrWriter, AST::Members::AttrAccessor
+          # nop
+        when AST::Ruby::Members::AttrReaderMember, AST::Ruby::Members::AttrWriterMember, AST::Ruby::Members::AttrAccessorMember
+          # nop
+        else
+          variables << tmp_var
+        end
+
         tmp_var = tmp_var.parent_variable
       end
 
@@ -602,6 +611,10 @@ def validate_variable(var)
         if r.source.instance_of?(AST::Members::ClassInstanceVariable) && l.declared_in == r.declared_in
           raise ClassInstanceVariableDuplicationError.new(type_name: l.declared_in, variable_name: l.source.name, location: l.source.location)
         end
+      when AST::Ruby::Members::InstanceVariableMember
+        if l.declared_in == r.declared_in
+          raise InstanceVariableDuplicationError.new(type_name: l.declared_in, variable_name: l.source.name, location: l.source.location)
+        end
       end
     end
 

test/rbs/definition_builder_test.rb

@@ -3645,4 +3645,28 @@ def initialize
       end
     end
   end
+
+  def test_inline_instance_variable_declarations_duplicates
+    SignatureManager.new do |manager|
+      manager.add_ruby_file("person.rb", <<~RUBY)
+        class Person
+          # @rbs @name: String
+          # @rbs @name: Integer
+
+          def initialize(name, age)
+            @name = name
+            @age = age
+          end
+        end
+      RUBY
+
+      manager.build do |env|
+        builder = DefinitionBuilder.new(env: env)
+
+        assert_raises RBS::InstanceVariableDuplicationError do
+          builder.build_instance(type_name("::Person"))
+        end
+      end
+    end
+  end
 end