--devtools panics if there is no console actor

[akosel]

This was mentioned in a comment here #5971 (comment). Basically, running servo with the --devtools flag leads to a crash.

When I run ./mach run http://google.com --devtools I get:

stack backtrace:

   1:        0x11060620f - sys::backtrace::write::h6990067d88907b48zVr
   2:        0x110609be4 - panicking::on_panic::he976cdbadffd9e1bEVv
   3:        0x1105f56c5 - rt::unwind::begin_unwind_inner::ha519446d83876aa8nDv
   4:        0x1105f5efc - rt::unwind::begin_unwind_fmt::h15c2d4adf8e8ecdatCv
   5:        0x11060949c - rust_begin_unwind
   6:        0x11062e945 - panicking::panic_fmt::haa553fbfab6eff2cNKy
   7:        0x10e80064f - option::Option<T>::expect::h2190493558643449847
   8:        0x10e800528 - collections::hash::map::HashMap<K, V, S>.Index<&'a Q>::index::h11570370938463914438
   9:        0x10e7fad25 - run_server::find_console_actor::h36bbabe37c10d21agJd
  10:        0x10e7edd07 - run_server::handle_network_event::h3503e9b8696ae0364Jd
  11:        0x10e7e0b99 - run_server::h865311e4cea3d37e6yd
  12:        0x10e7dfa33 - start_server::closure.13443
  13:        0x10e7df8dc - task::spawn_named::closure.13437
  14:        0x10e7df805 - boxed::F.FnBox<A>::call_box::h2076594675215285636
  15:        0x10e7aa51b - boxed::Box<FnBox<A, Output $u3d$$u20$R$GT$$u2b$$u20$Send$u20$$u2b$$u20$$u27$a$GT$.FnOnce$LT$A$GT$::call_once::h7459643712465505719
  16:        0x10e7a9b7b - thread::Builder::spawn_inner::closure.12797
  17:        0x10e7a9afe - rt::unwind::try::try_fn::__rust_abi::h742564627405228215
  18:        0x10e7a9a99 - rt::unwind::try::try_fn::h742564627405228215
  19:        0x11060b8d8 - rust_try_inner
  20:        0x11060b8c5 - rust_try
  21:        0x10e7a8f5a - rt::unwind::try::h12091752746280580590
  22:        0x10e7a8d04 - thread::Builder::spawn_inner::closure.12690
  23:        0x10e7aa85d - boxed::F.FnBox<A>::call_box::h15314979547732952471
  24:        0x11060856d - sys::thread::Thread::new::thread_start::h5fcf8fe12ec3c274mYu
  25:     0x7fff84fd3267 - _pthread_body
  26:     0x7fff84fd31e4 - _pthread_start

So the problem is that HashMap[“any_value”] will panic! if the lookup fails. The bigger problem seems to be that when find_console_actor is initially called, actor_pipelines is empty, so any lookup will fail.

@jdm noted that this is likely a regression from #5947

Given that this is related to the issue I am working on, I would be happy to take a crack at fixing this if it is fairly easy.

[jdm]

Go for it!

[akosel]

Sorry about the delay (vacation and moving); I was about to submit my pull request, but it looks like 6189 will fix this, so I am happy to defer to that.

[jdm]

No worries; sorry about the duplication of effort!

[boghison]

Shouldn't this be closed?

[jdm]

Not yet; #6189 wasn't merged and there's a new PR open to fix this.

[boghison]

Oh ok

[HarryLovesCode]

I think we can safely close this :)

#6540

[jdm]

Thanks!