From 8a42a6655982fe8f250de0dc65fb2a2e1692428a Mon Sep 17 00:00:00 2001
From: Alexander Momchilov <alexandermomchilov@gmail.com>
Date: Thu, 6 Jul 2023 22:12:51 -0400
Subject: [PATCH] Allow starting debug server without opening apps

---
 lib/debug/config.rb  |  2 +-
 lib/debug/server.rb  | 15 +++++++++++----
 lib/debug/session.rb |  8 +++++++-
 3 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/lib/debug/config.rb b/lib/debug/config.rb
index f6f1a066d..bcc9077f0 100644
--- a/lib/debug/config.rb
+++ b/lib/debug/config.rb
@@ -322,7 +322,7 @@ def self.parse_argv argv
           when 'tcp'
             config[:open] = true
             config[:port] ||= 0
-          when 'vscode', 'chrome', 'cdp'
+          when 'vscode', 'dap', 'chrome', 'cdp'
             config[:open] = f&.downcase
           else
             raise "Unknown option for --open: #{f}"
diff --git a/lib/debug/server.rb b/lib/debug/server.rb
index a67922ac1..1d435848d 100644
--- a/lib/debug/server.rb
+++ b/lib/debug/server.rb
@@ -374,9 +374,9 @@ def after_fork_parent
       # do nothing
     end
 
-    def vscode_setup debug_port
+    def vscode_setup debug_port, launch_vscode: true
       require_relative 'server_dap'
-      UI_DAP.setup debug_port
+      UI_DAP.setup debug_port if launch_vscode
     end
   end
 
@@ -440,8 +440,10 @@ def accept
           case CONFIG[:open]
           when 'chrome'
             chrome_setup
+          when 'dap-server' # Start in Debug Adapter Protocol mode without launching Visual Studio Code
+            vscode_setup @local_addr.inspect_sockaddr, launch_vscode: false
           when 'vscode'
-            vscode_setup @local_addr.inspect_sockaddr
+            vscode_setup @local_addr.inspect_sockaddr, launch_vscode: true
           end
 
           Socket.accept_loop(socks) do |sock, client|
@@ -494,7 +496,12 @@ def accept
       end
 
       ::DEBUGGER__.warn "Debugger can attach via UNIX domain socket (#{@sock_path})"
-      vscode_setup @sock_path if CONFIG[:open] == 'vscode'
+      case CONFIG[:open]
+      when 'dap-server' # Start in Debug Adapter Protocol mode without launching Visual Studio Code
+        vscode_setup @sock_path, launch_vscode: false
+      when 'vscode'
+        vscode_setup @sock_path, launch_vscode: true
+      end
 
       begin
         Socket.unix_server_loop @sock_path do |sock, client|
diff --git a/lib/debug/session.rb b/lib/debug/session.rb
index e9d95775c..4a1d99c94 100644
--- a/lib/debug/session.rb
+++ b/lib/debug/session.rb
@@ -1101,9 +1101,15 @@ def register_default_command
         when 'vscode'
           CONFIG[:open] = 'vscode'
           ::DEBUGGER__.open nonstop: true
-        when 'chrome', 'cdp'
+        when 'dap'
+          CONFIG[:open] = 'dap'
+          ::DEBUGGER__.open nonstop: true
+        when 'chrome'
           CONFIG[:open] = 'chrome'
           ::DEBUGGER__.open_tcp host: CONFIG[:host], port: (CONFIG[:port] || 0), nonstop: true
+        when 'cdp'
+          CONFIG[:open] = 'cdp'
+          ::DEBUGGER__.open_tcp host: CONFIG[:host], port: (CONFIG[:port] || 0), nonstop: true
         else
           raise "Unknown arg: #{arg}"
         end