DetailedTrace: Use fallback for anonymous classes

lib/graphql/tracing/perfetto_trace.rb

@@ -682,7 +682,7 @@ def payload_to_debug(k, v, iid: nil, intern_value: false)
         when GraphQL::Schema::InputObject
           payload_to_debug(k, v.to_h, iid: iid, intern_value: intern_value)
         else
-          class_name_iid = @interned_da_string_values[v.class.name]
+          class_name_iid = @interned_da_string_values[(v.class.name || "(anonymous)")]
           da = [
             debug_annotation(DA_DEBUG_INSPECT_CLASS_IID, :string_value_iid, class_name_iid),
           ]

spec/graphql/tracing/perfetto_trace_spec.rb

@@ -118,6 +118,7 @@ class SecretInput < GraphQL::Schema::InputObject
         class SecretThing < GraphQL::Schema::Object
           field :greeting, String
         end
+
         field :secret_field, SecretThing do
           argument :cipher, String, required: false
           argument :password, String, required: false
@@ -128,6 +129,7 @@ def secret_field(cipher: nil, password: nil, input: nil)
           {
             greeting: "Hello!",
             cipher: cipher || "FALLBACK_CIPHER",
+            anon: Class.new.new,
             password: password || (input ? input[0][0][:password] : "FALLBACK_PASSWORD"),
           }
         end
@@ -185,6 +187,13 @@ def self.detailed_trace?(q)
       check_snapshot(data, "example-rails-#{Rails::VERSION::MAJOR}-#{Rails::VERSION::MINOR}.json")
     end
 
+    it "replaces nil class name with (anonymous)" do
+      query_str = 'query getStuff { secretField { greeting } }'
+      res = PerfettoSchema.execute(query_str)
+      json = res.context.query.current_trace.write(file: nil, debug_json: true)
+      assert trace_includes?(json, "(anonymous)")
+    end
+
     it "filters params with Rails.application.config.filter_parameters" do
       query_str = 'query getStuff { secretField(cipher: "abcdef") { greeting } }'
       res = PerfettoSchema.execute(query_str)