Add helper to debug declaration context

Author: bjfish

src/main/java/org/truffleruby/debug/TruffleDebugNodes.java

@@ -25,6 +25,8 @@
 import org.truffleruby.builtins.CoreMethodArrayArgumentsNode;
 import org.truffleruby.builtins.CoreMethodNode;
 import org.truffleruby.builtins.CoreModule;
+import org.truffleruby.builtins.Primitive;
+import org.truffleruby.builtins.PrimitiveArrayArgumentsNode;
 import org.truffleruby.core.RubyHandle;
 import org.truffleruby.core.array.ArrayGuards;
 import org.truffleruby.core.array.ArrayHelpers;
@@ -48,6 +50,8 @@
 import org.truffleruby.language.ImmutableRubyObject;
 import org.truffleruby.language.NotProvided;
 import org.truffleruby.language.RubyDynamicObject;
+import org.truffleruby.language.arguments.RubyArguments;
+import org.truffleruby.language.methods.DeclarationContext;
 import org.truffleruby.language.methods.InternalMethod;
 import org.truffleruby.language.objects.AllocateHelperNode;
 import org.truffleruby.language.objects.shared.SharedObjects;
@@ -942,4 +946,18 @@ protected Object drainFinalizationQueue() {
 
     }
 
+    @Primitive(name = "frame_declaration_context_to_string")
+    public abstract static class FrameDeclarationContextToStringNode extends PrimitiveArrayArgumentsNode {
+
+        @Child private StringNodes.MakeStringNode makeStringNode = StringNodes.MakeStringNode.create();
+
+        @Specialization
+        protected RubyString getDeclarationContextToString(VirtualFrame frame) {
+            final DeclarationContext declarationContext = RubyArguments.getDeclarationContext(frame);
+            return makeStringNode
+                    .executeMake(declarationContext.toString(), UTF8Encoding.INSTANCE, CodeRange.CR_UNKNOWN);
+        }
+
+    }
+
 }

src/main/java/org/truffleruby/language/methods/DeclarationContext.java

@@ -165,4 +165,14 @@ public boolean hasRefinements() {
 
     /** Used when we know there cannot be a method definition inside a given method. */
     public static final DeclarationContext NONE = new DeclarationContext(Visibility.PUBLIC, null);
+
+    @TruffleBoundary
+    @Override
+    public String toString() {
+        return "DeclarationContext{" +
+                "visibility=" + visibility +
+                ", defaultDefinee=" + defaultDefinee +
+                ", refinements=" + refinements +
+                "}@" + hashCode();
+    }
 }