Add debug log level and instrument important internal events

lib/debug/config.rb

@@ -7,6 +7,7 @@ module DEBUGGER__
     ERROR:   2,
     WARN:    3,
     INFO:    4,
+    DEBUG:   5
   }.freeze
 
   CONFIG_SET = {

lib/debug/session.rb

@@ -2080,6 +2080,10 @@ def self.info msg
     log :INFO, msg
   end
 
+  def self.debug msg
+    log :DEBUG, msg
+  end
+
   def self.log level, msg
     @logfile = STDERR unless defined? @logfile
 

lib/debug/thread_client.rb

@@ -118,6 +118,7 @@ def mark_as_management
     end
 
     def set_mode mode
+      debug_mode(@mode, mode)
       # STDERR.puts "#{@mode} => #{mode} @ #{caller.inspect}"
       # pp caller
 
@@ -181,6 +182,7 @@ def puts str = ''
     end
 
     def << req
+      debug_cmd(req)
       @q_cmd << req
     end
 
@@ -191,6 +193,7 @@ def generate_info
     end
 
     def event! ev, *args
+      debug_event(ev, args)
       @q_evt << [self, @output, ev, generate_info, *args]
       @output = []
     end
@@ -236,6 +239,7 @@ def on_pause
 
     def suspend event, tp = nil, bp: nil, sig: nil, postmortem_frames: nil, replay_frames: nil, postmortem_exc: nil
       return if management?
+      debug_suspend(event)
 
       @current_frame_index = 0
 
@@ -1052,6 +1056,25 @@ def wait_next_action_
       raise
     end
 
+    def debug_event(ev, args)
+      args = args.map { |arg| DEBUGGER__.safe_inspect(arg) }
+      DEBUGGER__.debug("#{inspect} sends Event { type: #{ev.inspect}, args: #{args} } to Session")
+    end
+
+    def debug_mode(old_mode, new_mode)
+      DEBUGGER__.debug("#{inspect} changes mode (#{old_mode} -> #{new_mode})")
+    end
+
+    def debug_cmd(cmds)
+      cmd, *args = *cmds
+      args = args.map { |arg| DEBUGGER__.safe_inspect(arg) }
+      DEBUGGER__.debug("#{inspect} receives Cmd { type: #{cmd.inspect}, args: #{args} } from Session")
+    end
+
+    def debug_suspend(event)
+      DEBUGGER__.debug("#{inspect} is suspended for #{event.inspect}")
+    end
+
     class Recorder
       attr_reader :log, :index
       attr_accessor :backup_frames