Rescue SyntaxError in AutoInstruments

lib/scout_apm/auto_instrument/instruction_sequence.rb

@@ -4,19 +4,19 @@
 module ScoutApm
   module AutoInstrument
     module InstructionSequence
-      def load_iseq(path)
+      def self.load_iseq(path)
         if Rails.controller_path?(path) & !Rails.ignore?(path)
           begin
             new_code = Rails.rewrite(path)
-            return self.compile(new_code, path, path)
-          rescue
-            warn "Failed to apply auto-instrumentation to #{path}: #{$!}"
+            return ::RubyVM::InstructionSequence.compile(new_code, path, path)
+          rescue StandardError, SyntaxError
+            warn "Failed to apply auto-instrumentation to #{path}: #{$!}" if ENV['SCOUT_LOG_LEVEL'].to_s.downcase == "debug"
           end
         elsif Rails.ignore?(path)
-          warn "AutoInstruments are ignored for path=#{path}."
+          warn "AutoInstruments are ignored for path=#{path}." if ENV['SCOUT_LOG_LEVEL'].to_s.downcase == "debug"
         end
 
-        return self.compile_file(path)
+        return ::RubyVM::InstructionSequence.compile_file(path)
       end
     end
 

test/unit/auto_instrument/anonymous_block_value.rb → test/unit/auto_instrument/app/controllers/anonymous_block_value_controller.rb

@@ -1,4 +1,4 @@
-class TestController < ApplicationController
+class AutoInstrumentTestController
   def index
     quests = policy_scope(Quest.open)
     quests.each { _1.current_user = current_user }

test/unit/auto_instrument_test.rb

@@ -57,6 +57,8 @@ def test_hanging_method_rewrite
   end
 
   def test_anonymous_block_value
-    ::ScoutApm::AutoInstrument::Rails.rewrite(source_path("anonymous_block_value"))
+    ::ScoutApm::AutoInstrument::Rails.expects(:rewrite).once
+    ::RubyVM::InstructionSequence.expects(:compile).once
+    ::ScoutApm::AutoInstrument::InstructionSequence.load_iseq(source_path("app/controllers/anonymous_block_value_controller"))
   end
 end if defined? ScoutApm::AutoInstrument