VS Code breakpoints skipped after Rails reloads related code

Your environment

ruby -v: 3.1.2
rdbg -v: 1.7.0

Describe the bug

Breakpoints added via VS Code seems to be lost after surrounding code is modified and reloaded by Rails.

For example, if we set a breakpoint at

def index
  @posts = Post.all # set the breakpoint at this line
end

And then we insert a new line to the method:

def index
  puts "foo"
  @posts = Post.all # VS Code would move the breakpoint here after update
end

The breakpoint would not be triggered anymore.

To Reproduce

Clone this repo.
Run $ bundle install.
Run $ bundle exec bin/rails db:migrate RAILS_ENV=development.
Run $ bundle exec rdbg -O -n -c -- bundle exec bin/rails s to run the server with debugger in server mode.
Press F5 to attach VS Code to the debugger.
Go to app/controllers/posts_controller.rb and place an VS Code breakpoint at line 6.
```
def index
  @posts = Post.all # set the breakpoint at this line
end
```
Verify the breakpoint can be hit:
1. In browser, visit http://localhost:3000.
2. See the breakpoint being hit.
3. Press F5 again to continue the program.

Add puts "foo" at app/controllers/posts_controller.rb:6

def index
  puts "foo"
  @posts = Post.all
end

Refresh the page in browser.

Expected behavior

VS Code breakpoints can still trigger after the file is updated.

Additional context

When updating other methods, like adding something to the new method (10 lines away), the breakpoint still works. So I suspect it's related to the breakpoint's iseq being outdated?
From DAP server logs, it looks like the debugger does receive updated setBreakpoints request:

#25986:[>] {"command":"setBreakpoints","arguments":{"source":{"path":"/Users/hung-wulo/src/github.com/st0012/debug-issue/app/controllers/posts_controller.rb","name":"posts_controller.rb","sourceReference":0},"lines":[6],"breakpoints":[{"line":6}],"sourceModified":true},"type":"request","seq":13}
#25986:[<] {"type":"response","command":"setBreakpoints","request_seq":13,"success":true,"message":"Success","body":{"breakpoints":[{"verified":true}]},"seq":977}

But the breakpoint wasn't actually added/activated.

I think it's related to LineBreakpoint's @pending state:

After the first breakpoint hit, the later breakpoint would has @iseq like

<RubyVM::InstructionSequence:index@/Users/hung-wulo/src/github.com/st0012/debug-issue/app/controllers/posts_controller.rb:5>

And this means its @pending state would be false.

So when the :script_compiled event is triggered

bps_pending_until_load? would also be false
Thus ThreadClient.current.on_load wouldn't be triggered for the updated code
Which could have reloaded related LineBreakpoints

But I'm not sure which part is the root cause of the issue:

Should the later breakpoint's @iseq still be nil?
Should bps_pending_until_load? also take the bps' file path into consideration?
Or it could be something else?

Workaround

As a quick workaround, changing bps_pending_until_load? to just do @bps.any? seems to work.

Workaround ruby#870

Nothing to add other than to comment I have also been experiencing this bug. For the breakpoints to start registering after changing the code I have restart the server and attach the debug session again.

A fix for this would be great!

# repro code
File.write("l.rb", <<RUBY)
  # l.rb
  def foo # 2
    p 1   # 3
    p 2
  end
RUBY
load 'l.rb'
foo

debugger do: 'b l.rb:3'

p :loeaded

File.write("l.rb", <<RUBY)
  # l.rb
  def foo
    p 0
    p 1
    p 2
  end
RUBY

load 'l.rb'

foo

Sorry it is not a correct repro-code.
It needs VSCode interaction.

All right, I repro it.

File.write("l.rb", <<RUBY)
  # l.rb
  def foo
    p 1
  end
RUBY

load 'l.rb'
p :loeaded
debugger # set braekpoint at "l.rb:3" here

File.write("l.rb", <<RUBY)
  def foo
    p 0
    p 1
  end
RUBY

load 'l.rb'

foo

and next foo doesn't stop.

File.write("l.rb", <<RUBY)
  def foo
    p 1
  end
RUBY

load 'l.rb'
p :loeaded

debugger do: 'b l.rb:2'

foo

File.write("l.rb", <<RUBY)
  def foo
    p 0
    p 1
  end
RUBY

load 'l.rb'

foo

This is repro-code.

remain breakpoints on reloaded files

Merge v1.7.2 (#9)

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VS Code breakpoints skipped after Rails reloads related code #870

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VS Code breakpoints skipped after Rails reloads related code #870

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st0012 commented on Dec 16, 2022

Workaround

crobbo commented on Jan 13, 2023

ko1 commented on Mar 25, 2023

ko1 commented on Mar 25, 2023

ko1 commented on Mar 25, 2023

ko1 commented on Mar 25, 2023

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