Data#initialize supports String keywords

Author: eregon

spec/ruby/core/data/initialize_spec.rb

@@ -31,6 +31,13 @@
       data.unit.should == "km"
     end
 
+    it "accepts String keyword arguments" do
+      data = DataSpecs::Measure.new("amount" => 42, "unit" => "km")
+
+      data.amount.should == 42
+      data.unit.should == "km"
+    end
+
     it "raises ArgumentError if no arguments are given" do
       -> {
         DataSpecs::Measure.new

src/main/ruby/truffleruby/core/data.rb

@@ -84,12 +84,13 @@ def self.new(*args, **kwargs)
     # CRuby defines these directly on Data, but that is suboptimal for performance.
     # We want to have a specialized copy of these methods for each Data subclass.
     instance_methods_module = Module.new
-    instance_methods_module.module_eval "#{<<~'RUBY'}"
+    instance_methods_module.module_eval "#{<<~'RUBY'}", __FILE__, __LINE__+1
       # truffleruby_primitives: true
 
       def initialize(**kwargs)
         members_hash = Primitive.class(self)::CLASS_MEMBERS_HASH
         kwargs.each do |member, value|
+          member = member.to_sym
           if members_hash.include?(member)
             Primitive.object_hidden_var_set(self, member, value)
           else