From eeb306f1256f642c99a5e55c345c063c67a276eb Mon Sep 17 00:00:00 2001
From: David Peacock <david.peacock@shopify.com>
Date: Mon, 16 May 2022 01:19:33 -0400
Subject: [PATCH] Use levels and startFrame in DAP server backtrace

---
 lib/debug/server_dap.rb | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/debug/server_dap.rb b/lib/debug/server_dap.rb
index fcb7d1085..3754d231a 100644
--- a/lib/debug/server_dap.rb
+++ b/lib/debug/server_dap.rb
@@ -621,8 +621,11 @@ def process_dap args
 
       case type
       when :backtrace
+        levels = req.dig('arguments', 'levels') || @target_frames.length
+        startFrame = req.dig('arguments', 'startFrame') || 0
+
         event! :dap_result, :backtrace, req, {
-          stackFrames: @target_frames.map{|frame|
+          stackFrames: @target_frames[startFrame, levels].map{|frame|
             path = frame.realpath || frame.path
             source_name = path ? File.basename(path) : frame.location.to_s