draft of the Data() syntax

Author: HoneyryderChuck

test/rbs/parser_test.rb

@@ -428,6 +428,72 @@ def `: () -> void
     end
   end
 
+  def test_data_class_decl
+    RBS::Parser.parse_signature(buffer(<<-RBS)).tap do |_, _, decls|
+      class Foo < Data(a: Integer)
+      end
+          RBS
+      decls[0].tap do |decl|
+        assert_instance_of RBS::AST::Declarations::Class, decl
+        assert_equal TypeName("Foo"), decl.name
+        assert_predicate decl.type_params, :empty?
+        assert_nil decl.super_class.name
+        assert_equal TypeName("Data"), decl.super_class.superclass.name
+
+        assert_equal 8, decl.members.size
+
+        decl.members[0].tap do |member|
+          assert_instance_of RBS::AST::Members::AttrReader, member
+          assert_equal :instance, member.kind
+          assert_equal :a, member.name
+          assert_equal "Integer", member.type.to_s
+        end
+
+        decl.members[1].tap do |member|
+          assert_instance_of RBS::AST::Members::MethodDefinition, member
+          assert_equal :method, member.kind
+          assert_equal :initialize, member.name
+          assert_equal ["(::Integer) -> void | (id: ::Integer) -> void"], member.method_types.map(&:to_s)
+        end
+
+        decl.members[2].tap do |member|
+          assert_instance_of RBS::AST::Members::MethodDefinition, member
+          assert_equal :method, member.kind
+          assert_equal :members, member.name
+          assert_equal ["() -> Array[Symbol]"], member.method_types.map(&:to_s)
+        end
+
+        decl.members[3].tap do |member|
+          assert_instance_of RBS::AST::Members::MethodDefinition, member
+          assert_equal :method, member.kind
+          assert_equal :deconstruct, member.name
+          assert_equal ["() -> [Integer]"], member.method_types.map(&:to_s)
+        end
+
+        decl.members[4].tap do |member|
+          assert_instance_of RBS::AST::Members::MethodDefinition, member
+          assert_equal :method, member.kind
+          assert_equal :deconstruct_keys, member.name
+          assert_equal ["(nil) -> {a: Integer} | (Array(Symbol)) -> Hash[untyped]"], member.method_types.map(&:to_s)
+        end
+
+        decl.members[5].tap do |member|
+          assert_instance_of RBS::AST::Members::MethodDefinition, member
+          assert_equal :method, member.kind
+          assert_equal :with, member.name
+          assert_equal ["(?a: Integer) -> Foo"], member.method_types.map(&:to_s)
+        end
+      end
+
+      decls[1].tap do |decl|
+        # as funcall: Foo[1]
+        assert_instance_of RBS::Types::UntypedFunction, decl.block.type
+        assert_equal TypeName("Foo"), decl.name
+          assert_equal ["(::Integer a) -> Foo |(a: ::Integer) -> Foo"], member.method_types.map(&:to_s)
+      end
+    end
+  end
+
   def test_parse_type
     assert_equal "hello", RBS::Parser.parse_type(buffer('"hello"')).literal
     assert_equal "hello", RBS::Parser.parse_type(buffer("'hello'")).literal